1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Kernel-based Virtual Machine driver for Linux
4 *
5 * derived from drivers/kvm/kvm_main.c
6 *
7 * Copyright (C) 2006 Qumranet, Inc.
8 * Copyright (C) 2008 Qumranet, Inc.
9 * Copyright IBM Corporation, 2008
10 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
11 *
12 * Authors:
13 * Avi Kivity <avi@qumranet.com>
14 * Yaniv Kamay <yaniv@qumranet.com>
15 * Amit Shah <amit.shah@qumranet.com>
16 * Ben-Ami Yassour <benami@il.ibm.com>
17 */
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
20 #include <linux/kvm_host.h>
21 #include "irq.h"
22 #include "ioapic.h"
23 #include "mmu.h"
24 #include "i8254.h"
25 #include "tss.h"
26 #include "kvm_cache_regs.h"
27 #include "kvm_emulate.h"
28 #include "mmu/page_track.h"
29 #include "x86.h"
30 #include "cpuid.h"
31 #include "pmu.h"
32 #include "hyperv.h"
33 #include "lapic.h"
34 #include "xen.h"
35 #include "smm.h"
36
37 #include <linux/clocksource.h>
38 #include <linux/interrupt.h>
39 #include <linux/kvm.h>
40 #include <linux/fs.h>
41 #include <linux/vmalloc.h>
42 #include <linux/export.h>
43 #include <linux/moduleparam.h>
44 #include <linux/mman.h>
45 #include <linux/highmem.h>
46 #include <linux/iommu.h>
47 #include <linux/cpufreq.h>
48 #include <linux/user-return-notifier.h>
49 #include <linux/srcu.h>
50 #include <linux/slab.h>
51 #include <linux/perf_event.h>
52 #include <linux/uaccess.h>
53 #include <linux/hash.h>
54 #include <linux/pci.h>
55 #include <linux/timekeeper_internal.h>
56 #include <linux/pvclock_gtod.h>
57 #include <linux/kvm_irqfd.h>
58 #include <linux/irqbypass.h>
59 #include <linux/sched/stat.h>
60 #include <linux/sched/isolation.h>
61 #include <linux/mem_encrypt.h>
62 #include <linux/entry-kvm.h>
63 #include <linux/suspend.h>
64 #include <linux/smp.h>
65
66 #include <trace/events/ipi.h>
67 #include <trace/events/kvm.h>
68
69 #include <asm/debugreg.h>
70 #include <asm/msr.h>
71 #include <asm/desc.h>
72 #include <asm/mce.h>
73 #include <asm/pkru.h>
74 #include <linux/kernel_stat.h>
75 #include <asm/fpu/api.h>
76 #include <asm/fpu/xcr.h>
77 #include <asm/fpu/xstate.h>
78 #include <asm/pvclock.h>
79 #include <asm/div64.h>
80 #include <asm/irq_remapping.h>
81 #include <asm/mshyperv.h>
82 #include <asm/hypervisor.h>
83 #include <asm/tlbflush.h>
84 #include <asm/intel_pt.h>
85 #include <asm/emulate_prefix.h>
86 #include <asm/sgx.h>
87 #include <clocksource/hyperv_timer.h>
88
89 #define CREATE_TRACE_POINTS
90 #include "trace.h"
91
92 #define MAX_IO_MSRS 256
93
94 /*
95 * Note, kvm_caps fields should *never* have default values, all fields must be
96 * recomputed from scratch during vendor module load, e.g. to account for a
97 * vendor module being reloaded with different module parameters.
98 */
99 struct kvm_caps kvm_caps __read_mostly;
100 EXPORT_SYMBOL_GPL(kvm_caps);
101
102 struct kvm_host_values kvm_host __read_mostly;
103 EXPORT_SYMBOL_GPL(kvm_host);
104
105 #define ERR_PTR_USR(e) ((void __user *)ERR_PTR(e))
106
107 #define emul_to_vcpu(ctxt) \
108 ((struct kvm_vcpu *)(ctxt)->vcpu)
109
110 /* EFER defaults:
111 * - enable syscall per default because its emulated by KVM
112 * - enable LME and LMA per default on 64 bit KVM
113 */
114 #ifdef CONFIG_X86_64
115 static
116 u64 __read_mostly efer_reserved_bits = ~((u64)(EFER_SCE | EFER_LME | EFER_LMA));
117 #else
118 static u64 __read_mostly efer_reserved_bits = ~((u64)EFER_SCE);
119 #endif
120
121 #define KVM_EXIT_HYPERCALL_VALID_MASK (1 << KVM_HC_MAP_GPA_RANGE)
122
123 #define KVM_CAP_PMU_VALID_MASK KVM_PMU_CAP_DISABLE
124
125 #define KVM_X2APIC_API_VALID_FLAGS (KVM_X2APIC_API_USE_32BIT_IDS | \
126 KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK)
127
128 static void update_cr8_intercept(struct kvm_vcpu *vcpu);
129 static void process_nmi(struct kvm_vcpu *vcpu);
130 static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
131 static void store_regs(struct kvm_vcpu *vcpu);
132 static int sync_regs(struct kvm_vcpu *vcpu);
133 static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu);
134
135 static int __set_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2);
136 static void __get_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2);
137
138 static DEFINE_MUTEX(vendor_module_lock);
139 struct kvm_x86_ops kvm_x86_ops __read_mostly;
140
141 #define KVM_X86_OP(func) \
142 DEFINE_STATIC_CALL_NULL(kvm_x86_##func, \
143 *(((struct kvm_x86_ops *)0)->func));
144 #define KVM_X86_OP_OPTIONAL KVM_X86_OP
145 #define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP
146 #include <asm/kvm-x86-ops.h>
147 EXPORT_STATIC_CALL_GPL(kvm_x86_get_cs_db_l_bits);
148 EXPORT_STATIC_CALL_GPL(kvm_x86_cache_reg);
149
150 static bool __read_mostly ignore_msrs = 0;
151 module_param(ignore_msrs, bool, 0644);
152
153 bool __read_mostly report_ignored_msrs = true;
154 module_param(report_ignored_msrs, bool, 0644);
155 EXPORT_SYMBOL_GPL(report_ignored_msrs);
156
157 unsigned int min_timer_period_us = 200;
158 module_param(min_timer_period_us, uint, 0644);
159
160 static bool __read_mostly kvmclock_periodic_sync = true;
161 module_param(kvmclock_periodic_sync, bool, 0444);
162
163 /* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */
164 static u32 __read_mostly tsc_tolerance_ppm = 250;
165 module_param(tsc_tolerance_ppm, uint, 0644);
166
167 static bool __read_mostly vector_hashing = true;
168 module_param(vector_hashing, bool, 0444);
169
170 bool __read_mostly enable_vmware_backdoor = false;
171 module_param(enable_vmware_backdoor, bool, 0444);
172 EXPORT_SYMBOL_GPL(enable_vmware_backdoor);
173
174 /*
175 * Flags to manipulate forced emulation behavior (any non-zero value will
176 * enable forced emulation).
177 */
178 #define KVM_FEP_CLEAR_RFLAGS_RF BIT(1)
179 static int __read_mostly force_emulation_prefix;
180 module_param(force_emulation_prefix, int, 0644);
181
182 int __read_mostly pi_inject_timer = -1;
183 module_param(pi_inject_timer, bint, 0644);
184
185 /* Enable/disable PMU virtualization */
186 bool __read_mostly enable_pmu = true;
187 EXPORT_SYMBOL_GPL(enable_pmu);
188 module_param(enable_pmu, bool, 0444);
189
190 bool __read_mostly eager_page_split = true;
191 module_param(eager_page_split, bool, 0644);
192
193 /* Enable/disable SMT_RSB bug mitigation */
194 static bool __read_mostly mitigate_smt_rsb;
195 module_param(mitigate_smt_rsb, bool, 0444);
196
197 /*
198 * Restoring the host value for MSRs that are only consumed when running in
199 * usermode, e.g. SYSCALL MSRs and TSC_AUX, can be deferred until the CPU
200 * returns to userspace, i.e. the kernel can run with the guest's value.
201 */
202 #define KVM_MAX_NR_USER_RETURN_MSRS 16
203
204 struct kvm_user_return_msrs {
205 struct user_return_notifier urn;
206 bool registered;
207 struct kvm_user_return_msr_values {
208 u64 host;
209 u64 curr;
210 } values[KVM_MAX_NR_USER_RETURN_MSRS];
211 };
212
213 u32 __read_mostly kvm_nr_uret_msrs;
214 EXPORT_SYMBOL_GPL(kvm_nr_uret_msrs);
215 static u32 __read_mostly kvm_uret_msrs_list[KVM_MAX_NR_USER_RETURN_MSRS];
216 static struct kvm_user_return_msrs __percpu *user_return_msrs;
217
218 #define KVM_SUPPORTED_XCR0 (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \
219 | XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \
220 | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \
221 | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE)
222
223 bool __read_mostly allow_smaller_maxphyaddr = 0;
224 EXPORT_SYMBOL_GPL(allow_smaller_maxphyaddr);
225
226 bool __read_mostly enable_apicv = true;
227 EXPORT_SYMBOL_GPL(enable_apicv);
228
229 bool __read_mostly enable_ipiv = true;
230 EXPORT_SYMBOL_GPL(enable_ipiv);
231
232 bool __read_mostly enable_device_posted_irqs = true;
233 EXPORT_SYMBOL_GPL(enable_device_posted_irqs);
234
235 const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
236 KVM_GENERIC_VM_STATS(),
237 STATS_DESC_COUNTER(VM, mmu_shadow_zapped),
238 STATS_DESC_COUNTER(VM, mmu_pte_write),
239 STATS_DESC_COUNTER(VM, mmu_pde_zapped),
240 STATS_DESC_COUNTER(VM, mmu_flooded),
241 STATS_DESC_COUNTER(VM, mmu_recycled),
242 STATS_DESC_COUNTER(VM, mmu_cache_miss),
243 STATS_DESC_ICOUNTER(VM, mmu_unsync),
244 STATS_DESC_ICOUNTER(VM, pages_4k),
245 STATS_DESC_ICOUNTER(VM, pages_2m),
246 STATS_DESC_ICOUNTER(VM, pages_1g),
247 STATS_DESC_ICOUNTER(VM, nx_lpage_splits),
248 STATS_DESC_PCOUNTER(VM, max_mmu_rmap_size),
249 STATS_DESC_PCOUNTER(VM, max_mmu_page_hash_collisions)
250 };
251
252 const struct kvm_stats_header kvm_vm_stats_header = {
253 .name_size = KVM_STATS_NAME_SIZE,
254 .num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
255 .id_offset = sizeof(struct kvm_stats_header),
256 .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
257 .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
258 sizeof(kvm_vm_stats_desc),
259 };
260
261 const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
262 KVM_GENERIC_VCPU_STATS(),
263 STATS_DESC_COUNTER(VCPU, pf_taken),
264 STATS_DESC_COUNTER(VCPU, pf_fixed),
265 STATS_DESC_COUNTER(VCPU, pf_emulate),
266 STATS_DESC_COUNTER(VCPU, pf_spurious),
267 STATS_DESC_COUNTER(VCPU, pf_fast),
268 STATS_DESC_COUNTER(VCPU, pf_mmio_spte_created),
269 STATS_DESC_COUNTER(VCPU, pf_guest),
270 STATS_DESC_COUNTER(VCPU, tlb_flush),
271 STATS_DESC_COUNTER(VCPU, invlpg),
272 STATS_DESC_COUNTER(VCPU, exits),
273 STATS_DESC_COUNTER(VCPU, io_exits),
274 STATS_DESC_COUNTER(VCPU, mmio_exits),
275 STATS_DESC_COUNTER(VCPU, signal_exits),
276 STATS_DESC_COUNTER(VCPU, irq_window_exits),
277 STATS_DESC_COUNTER(VCPU, nmi_window_exits),
278 STATS_DESC_COUNTER(VCPU, l1d_flush),
279 STATS_DESC_COUNTER(VCPU, halt_exits),
280 STATS_DESC_COUNTER(VCPU, request_irq_exits),
281 STATS_DESC_COUNTER(VCPU, irq_exits),
282 STATS_DESC_COUNTER(VCPU, host_state_reload),
283 STATS_DESC_COUNTER(VCPU, fpu_reload),
284 STATS_DESC_COUNTER(VCPU, insn_emulation),
285 STATS_DESC_COUNTER(VCPU, insn_emulation_fail),
286 STATS_DESC_COUNTER(VCPU, hypercalls),
287 STATS_DESC_COUNTER(VCPU, irq_injections),
288 STATS_DESC_COUNTER(VCPU, nmi_injections),
289 STATS_DESC_COUNTER(VCPU, req_event),
290 STATS_DESC_COUNTER(VCPU, nested_run),
291 STATS_DESC_COUNTER(VCPU, directed_yield_attempted),
292 STATS_DESC_COUNTER(VCPU, directed_yield_successful),
293 STATS_DESC_COUNTER(VCPU, preemption_reported),
294 STATS_DESC_COUNTER(VCPU, preemption_other),
295 STATS_DESC_IBOOLEAN(VCPU, guest_mode),
296 STATS_DESC_COUNTER(VCPU, notify_window_exits),
297 };
298
299 const struct kvm_stats_header kvm_vcpu_stats_header = {
300 .name_size = KVM_STATS_NAME_SIZE,
301 .num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
302 .id_offset = sizeof(struct kvm_stats_header),
303 .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
304 .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
305 sizeof(kvm_vcpu_stats_desc),
306 };
307
308 static struct kmem_cache *x86_emulator_cache;
309
310 /*
311 * The three MSR lists(msrs_to_save, emulated_msrs, msr_based_features) track
312 * the set of MSRs that KVM exposes to userspace through KVM_GET_MSRS,
313 * KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST. msrs_to_save holds MSRs that
314 * require host support, i.e. should be probed via RDMSR. emulated_msrs holds
315 * MSRs that KVM emulates without strictly requiring host support.
316 * msr_based_features holds MSRs that enumerate features, i.e. are effectively
317 * CPUID leafs. Note, msr_based_features isn't mutually exclusive with
318 * msrs_to_save and emulated_msrs.
319 */
320
321 static const u32 msrs_to_save_base[] = {
322 MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
323 MSR_STAR,
324 #ifdef CONFIG_X86_64
325 MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
326 #endif
327 MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA,
328 MSR_IA32_FEAT_CTL, MSR_IA32_BNDCFGS, MSR_TSC_AUX,
329 MSR_IA32_SPEC_CTRL, MSR_IA32_TSX_CTRL,
330 MSR_IA32_RTIT_CTL, MSR_IA32_RTIT_STATUS, MSR_IA32_RTIT_CR3_MATCH,
331 MSR_IA32_RTIT_OUTPUT_BASE, MSR_IA32_RTIT_OUTPUT_MASK,
332 MSR_IA32_RTIT_ADDR0_A, MSR_IA32_RTIT_ADDR0_B,
333 MSR_IA32_RTIT_ADDR1_A, MSR_IA32_RTIT_ADDR1_B,
334 MSR_IA32_RTIT_ADDR2_A, MSR_IA32_RTIT_ADDR2_B,
335 MSR_IA32_RTIT_ADDR3_A, MSR_IA32_RTIT_ADDR3_B,
336 MSR_IA32_UMWAIT_CONTROL,
337
338 MSR_IA32_XFD, MSR_IA32_XFD_ERR,
339 };
340
341 static const u32 msrs_to_save_pmu[] = {
342 MSR_ARCH_PERFMON_FIXED_CTR0, MSR_ARCH_PERFMON_FIXED_CTR1,
343 MSR_ARCH_PERFMON_FIXED_CTR0 + 2,
344 MSR_CORE_PERF_FIXED_CTR_CTRL, MSR_CORE_PERF_GLOBAL_STATUS,
345 MSR_CORE_PERF_GLOBAL_CTRL,
346 MSR_IA32_PEBS_ENABLE, MSR_IA32_DS_AREA, MSR_PEBS_DATA_CFG,
347
348 /* This part of MSRs should match KVM_MAX_NR_INTEL_GP_COUNTERS. */
349 MSR_ARCH_PERFMON_PERFCTR0, MSR_ARCH_PERFMON_PERFCTR1,
350 MSR_ARCH_PERFMON_PERFCTR0 + 2, MSR_ARCH_PERFMON_PERFCTR0 + 3,
351 MSR_ARCH_PERFMON_PERFCTR0 + 4, MSR_ARCH_PERFMON_PERFCTR0 + 5,
352 MSR_ARCH_PERFMON_PERFCTR0 + 6, MSR_ARCH_PERFMON_PERFCTR0 + 7,
353 MSR_ARCH_PERFMON_EVENTSEL0, MSR_ARCH_PERFMON_EVENTSEL1,
354 MSR_ARCH_PERFMON_EVENTSEL0 + 2, MSR_ARCH_PERFMON_EVENTSEL0 + 3,
355 MSR_ARCH_PERFMON_EVENTSEL0 + 4, MSR_ARCH_PERFMON_EVENTSEL0 + 5,
356 MSR_ARCH_PERFMON_EVENTSEL0 + 6, MSR_ARCH_PERFMON_EVENTSEL0 + 7,
357
358 MSR_K7_EVNTSEL0, MSR_K7_EVNTSEL1, MSR_K7_EVNTSEL2, MSR_K7_EVNTSEL3,
359 MSR_K7_PERFCTR0, MSR_K7_PERFCTR1, MSR_K7_PERFCTR2, MSR_K7_PERFCTR3,
360
361 /* This part of MSRs should match KVM_MAX_NR_AMD_GP_COUNTERS. */
362 MSR_F15H_PERF_CTL0, MSR_F15H_PERF_CTL1, MSR_F15H_PERF_CTL2,
363 MSR_F15H_PERF_CTL3, MSR_F15H_PERF_CTL4, MSR_F15H_PERF_CTL5,
364 MSR_F15H_PERF_CTR0, MSR_F15H_PERF_CTR1, MSR_F15H_PERF_CTR2,
365 MSR_F15H_PERF_CTR3, MSR_F15H_PERF_CTR4, MSR_F15H_PERF_CTR5,
366
367 MSR_AMD64_PERF_CNTR_GLOBAL_CTL,
368 MSR_AMD64_PERF_CNTR_GLOBAL_STATUS,
369 MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR,
370 };
371
372 static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_base) +
373 ARRAY_SIZE(msrs_to_save_pmu)];
374 static unsigned num_msrs_to_save;
375
376 static const u32 emulated_msrs_all[] = {
377 MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
378 MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW,
379
380 #ifdef CONFIG_KVM_HYPERV
381 HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL,
382 HV_X64_MSR_TIME_REF_COUNT, HV_X64_MSR_REFERENCE_TSC,
383 HV_X64_MSR_TSC_FREQUENCY, HV_X64_MSR_APIC_FREQUENCY,
384 HV_X64_MSR_CRASH_P0, HV_X64_MSR_CRASH_P1, HV_X64_MSR_CRASH_P2,
385 HV_X64_MSR_CRASH_P3, HV_X64_MSR_CRASH_P4, HV_X64_MSR_CRASH_CTL,
386 HV_X64_MSR_RESET,
387 HV_X64_MSR_VP_INDEX,
388 HV_X64_MSR_VP_RUNTIME,
389 HV_X64_MSR_SCONTROL,
390 HV_X64_MSR_STIMER0_CONFIG,
391 HV_X64_MSR_VP_ASSIST_PAGE,
392 HV_X64_MSR_REENLIGHTENMENT_CONTROL, HV_X64_MSR_TSC_EMULATION_CONTROL,
393 HV_X64_MSR_TSC_EMULATION_STATUS, HV_X64_MSR_TSC_INVARIANT_CONTROL,
394 HV_X64_MSR_SYNDBG_OPTIONS,
395 HV_X64_MSR_SYNDBG_CONTROL, HV_X64_MSR_SYNDBG_STATUS,
396 HV_X64_MSR_SYNDBG_SEND_BUFFER, HV_X64_MSR_SYNDBG_RECV_BUFFER,
397 HV_X64_MSR_SYNDBG_PENDING_BUFFER,
398 #endif
399
400 MSR_KVM_ASYNC_PF_EN, MSR_KVM_STEAL_TIME,
401 MSR_KVM_PV_EOI_EN, MSR_KVM_ASYNC_PF_INT, MSR_KVM_ASYNC_PF_ACK,
402
403 MSR_IA32_TSC_ADJUST,
404 MSR_IA32_TSC_DEADLINE,
405 MSR_IA32_ARCH_CAPABILITIES,
406 MSR_IA32_PERF_CAPABILITIES,
407 MSR_IA32_MISC_ENABLE,
408 MSR_IA32_MCG_STATUS,
409 MSR_IA32_MCG_CTL,
410 MSR_IA32_MCG_EXT_CTL,
411 MSR_IA32_SMBASE,
412 MSR_SMI_COUNT,
413 MSR_PLATFORM_INFO,
414 MSR_MISC_FEATURES_ENABLES,
415 MSR_AMD64_VIRT_SPEC_CTRL,
416 MSR_AMD64_TSC_RATIO,
417 MSR_IA32_POWER_CTL,
418 MSR_IA32_UCODE_REV,
419
420 /*
421 * KVM always supports the "true" VMX control MSRs, even if the host
422 * does not. The VMX MSRs as a whole are considered "emulated" as KVM
423 * doesn't strictly require them to exist in the host (ignoring that
424 * KVM would refuse to load in the first place if the core set of MSRs
425 * aren't supported).
426 */
427 MSR_IA32_VMX_BASIC,
428 MSR_IA32_VMX_TRUE_PINBASED_CTLS,
429 MSR_IA32_VMX_TRUE_PROCBASED_CTLS,
430 MSR_IA32_VMX_TRUE_EXIT_CTLS,
431 MSR_IA32_VMX_TRUE_ENTRY_CTLS,
432 MSR_IA32_VMX_MISC,
433 MSR_IA32_VMX_CR0_FIXED0,
434 MSR_IA32_VMX_CR4_FIXED0,
435 MSR_IA32_VMX_VMCS_ENUM,
436 MSR_IA32_VMX_PROCBASED_CTLS2,
437 MSR_IA32_VMX_EPT_VPID_CAP,
438 MSR_IA32_VMX_VMFUNC,
439
440 MSR_K7_HWCR,
441 MSR_KVM_POLL_CONTROL,
442 };
443
444 static u32 emulated_msrs[ARRAY_SIZE(emulated_msrs_all)];
445 static unsigned num_emulated_msrs;
446
447 /*
448 * List of MSRs that control the existence of MSR-based features, i.e. MSRs
449 * that are effectively CPUID leafs. VMX MSRs are also included in the set of
450 * feature MSRs, but are handled separately to allow expedited lookups.
451 */
452 static const u32 msr_based_features_all_except_vmx[] = {
453 MSR_AMD64_DE_CFG,
454 MSR_IA32_UCODE_REV,
455 MSR_IA32_ARCH_CAPABILITIES,
456 MSR_IA32_PERF_CAPABILITIES,
457 MSR_PLATFORM_INFO,
458 };
459
460 static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all_except_vmx) +
461 (KVM_LAST_EMULATED_VMX_MSR - KVM_FIRST_EMULATED_VMX_MSR + 1)];
462 static unsigned int num_msr_based_features;
463
464 /*
465 * All feature MSRs except uCode revID, which tracks the currently loaded uCode
466 * patch, are immutable once the vCPU model is defined.
467 */
kvm_is_immutable_feature_msr(u32 msr)468 static bool kvm_is_immutable_feature_msr(u32 msr)
469 {
470 int i;
471
472 if (msr >= KVM_FIRST_EMULATED_VMX_MSR && msr <= KVM_LAST_EMULATED_VMX_MSR)
473 return true;
474
475 for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++) {
476 if (msr == msr_based_features_all_except_vmx[i])
477 return msr != MSR_IA32_UCODE_REV;
478 }
479
480 return false;
481 }
482
kvm_is_advertised_msr(u32 msr_index)483 static bool kvm_is_advertised_msr(u32 msr_index)
484 {
485 unsigned int i;
486
487 for (i = 0; i < num_msrs_to_save; i++) {
488 if (msrs_to_save[i] == msr_index)
489 return true;
490 }
491
492 for (i = 0; i < num_emulated_msrs; i++) {
493 if (emulated_msrs[i] == msr_index)
494 return true;
495 }
496
497 return false;
498 }
499
500 typedef int (*msr_access_t)(struct kvm_vcpu *vcpu, u32 index, u64 *data,
501 bool host_initiated);
502
kvm_do_msr_access(struct kvm_vcpu * vcpu,u32 msr,u64 * data,bool host_initiated,enum kvm_msr_access rw,msr_access_t msr_access_fn)503 static __always_inline int kvm_do_msr_access(struct kvm_vcpu *vcpu, u32 msr,
504 u64 *data, bool host_initiated,
505 enum kvm_msr_access rw,
506 msr_access_t msr_access_fn)
507 {
508 const char *op = rw == MSR_TYPE_W ? "wrmsr" : "rdmsr";
509 int ret;
510
511 BUILD_BUG_ON(rw != MSR_TYPE_R && rw != MSR_TYPE_W);
512
513 /*
514 * Zero the data on read failures to avoid leaking stack data to the
515 * guest and/or userspace, e.g. if the failure is ignored below.
516 */
517 ret = msr_access_fn(vcpu, msr, data, host_initiated);
518 if (ret && rw == MSR_TYPE_R)
519 *data = 0;
520
521 if (ret != KVM_MSR_RET_UNSUPPORTED)
522 return ret;
523
524 /*
525 * Userspace is allowed to read MSRs, and write '0' to MSRs, that KVM
526 * advertises to userspace, even if an MSR isn't fully supported.
527 * Simply check that @data is '0', which covers both the write '0' case
528 * and all reads (in which case @data is zeroed on failure; see above).
529 */
530 if (host_initiated && !*data && kvm_is_advertised_msr(msr))
531 return 0;
532
533 if (!ignore_msrs) {
534 kvm_debug_ratelimited("unhandled %s: 0x%x data 0x%llx\n",
535 op, msr, *data);
536 return ret;
537 }
538
539 if (report_ignored_msrs)
540 kvm_pr_unimpl("ignored %s: 0x%x data 0x%llx\n", op, msr, *data);
541
542 return 0;
543 }
544
kvm_alloc_emulator_cache(void)545 static struct kmem_cache *kvm_alloc_emulator_cache(void)
546 {
547 unsigned int useroffset = offsetof(struct x86_emulate_ctxt, src);
548 unsigned int size = sizeof(struct x86_emulate_ctxt);
549
550 return kmem_cache_create_usercopy("x86_emulator", size,
551 __alignof__(struct x86_emulate_ctxt),
552 SLAB_ACCOUNT, useroffset,
553 size - useroffset, NULL);
554 }
555
556 static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt);
557
kvm_async_pf_hash_reset(struct kvm_vcpu * vcpu)558 static inline void kvm_async_pf_hash_reset(struct kvm_vcpu *vcpu)
559 {
560 int i;
561 for (i = 0; i < ASYNC_PF_PER_VCPU; i++)
562 vcpu->arch.apf.gfns[i] = ~0;
563 }
564
kvm_on_user_return(struct user_return_notifier * urn)565 static void kvm_on_user_return(struct user_return_notifier *urn)
566 {
567 unsigned slot;
568 struct kvm_user_return_msrs *msrs
569 = container_of(urn, struct kvm_user_return_msrs, urn);
570 struct kvm_user_return_msr_values *values;
571 unsigned long flags;
572
573 /*
574 * Disabling irqs at this point since the following code could be
575 * interrupted and executed through kvm_arch_disable_virtualization_cpu()
576 */
577 local_irq_save(flags);
578 if (msrs->registered) {
579 msrs->registered = false;
580 user_return_notifier_unregister(urn);
581 }
582 local_irq_restore(flags);
583 for (slot = 0; slot < kvm_nr_uret_msrs; ++slot) {
584 values = &msrs->values[slot];
585 if (values->host != values->curr) {
586 wrmsrq(kvm_uret_msrs_list[slot], values->host);
587 values->curr = values->host;
588 }
589 }
590 }
591
kvm_probe_user_return_msr(u32 msr)592 static int kvm_probe_user_return_msr(u32 msr)
593 {
594 u64 val;
595 int ret;
596
597 preempt_disable();
598 ret = rdmsrq_safe(msr, &val);
599 if (ret)
600 goto out;
601 ret = wrmsrq_safe(msr, val);
602 out:
603 preempt_enable();
604 return ret;
605 }
606
kvm_add_user_return_msr(u32 msr)607 int kvm_add_user_return_msr(u32 msr)
608 {
609 BUG_ON(kvm_nr_uret_msrs >= KVM_MAX_NR_USER_RETURN_MSRS);
610
611 if (kvm_probe_user_return_msr(msr))
612 return -1;
613
614 kvm_uret_msrs_list[kvm_nr_uret_msrs] = msr;
615 return kvm_nr_uret_msrs++;
616 }
617 EXPORT_SYMBOL_GPL(kvm_add_user_return_msr);
618
kvm_find_user_return_msr(u32 msr)619 int kvm_find_user_return_msr(u32 msr)
620 {
621 int i;
622
623 for (i = 0; i < kvm_nr_uret_msrs; ++i) {
624 if (kvm_uret_msrs_list[i] == msr)
625 return i;
626 }
627 return -1;
628 }
629 EXPORT_SYMBOL_GPL(kvm_find_user_return_msr);
630
kvm_user_return_msr_cpu_online(void)631 static void kvm_user_return_msr_cpu_online(void)
632 {
633 struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs);
634 u64 value;
635 int i;
636
637 for (i = 0; i < kvm_nr_uret_msrs; ++i) {
638 rdmsrq_safe(kvm_uret_msrs_list[i], &value);
639 msrs->values[i].host = value;
640 msrs->values[i].curr = value;
641 }
642 }
643
kvm_user_return_register_notifier(struct kvm_user_return_msrs * msrs)644 static void kvm_user_return_register_notifier(struct kvm_user_return_msrs *msrs)
645 {
646 if (!msrs->registered) {
647 msrs->urn.on_user_return = kvm_on_user_return;
648 user_return_notifier_register(&msrs->urn);
649 msrs->registered = true;
650 }
651 }
652
kvm_set_user_return_msr(unsigned slot,u64 value,u64 mask)653 int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask)
654 {
655 struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs);
656 int err;
657
658 value = (value & mask) | (msrs->values[slot].host & ~mask);
659 if (value == msrs->values[slot].curr)
660 return 0;
661 err = wrmsrq_safe(kvm_uret_msrs_list[slot], value);
662 if (err)
663 return 1;
664
665 msrs->values[slot].curr = value;
666 kvm_user_return_register_notifier(msrs);
667 return 0;
668 }
669 EXPORT_SYMBOL_GPL(kvm_set_user_return_msr);
670
kvm_user_return_msr_update_cache(unsigned int slot,u64 value)671 void kvm_user_return_msr_update_cache(unsigned int slot, u64 value)
672 {
673 struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs);
674
675 msrs->values[slot].curr = value;
676 kvm_user_return_register_notifier(msrs);
677 }
678 EXPORT_SYMBOL_GPL(kvm_user_return_msr_update_cache);
679
drop_user_return_notifiers(void)680 static void drop_user_return_notifiers(void)
681 {
682 struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs);
683
684 if (msrs->registered)
685 kvm_on_user_return(&msrs->urn);
686 }
687
688 /*
689 * Handle a fault on a hardware virtualization (VMX or SVM) instruction.
690 *
691 * Hardware virtualization extension instructions may fault if a reboot turns
692 * off virtualization while processes are running. Usually after catching the
693 * fault we just panic; during reboot instead the instruction is ignored.
694 */
kvm_spurious_fault(void)695 noinstr void kvm_spurious_fault(void)
696 {
697 /* Fault while not rebooting. We want the trace. */
698 BUG_ON(!kvm_rebooting);
699 }
700 EXPORT_SYMBOL_GPL(kvm_spurious_fault);
701
702 #define EXCPT_BENIGN 0
703 #define EXCPT_CONTRIBUTORY 1
704 #define EXCPT_PF 2
705
exception_class(int vector)706 static int exception_class(int vector)
707 {
708 switch (vector) {
709 case PF_VECTOR:
710 return EXCPT_PF;
711 case DE_VECTOR:
712 case TS_VECTOR:
713 case NP_VECTOR:
714 case SS_VECTOR:
715 case GP_VECTOR:
716 return EXCPT_CONTRIBUTORY;
717 default:
718 break;
719 }
720 return EXCPT_BENIGN;
721 }
722
723 #define EXCPT_FAULT 0
724 #define EXCPT_TRAP 1
725 #define EXCPT_ABORT 2
726 #define EXCPT_INTERRUPT 3
727 #define EXCPT_DB 4
728
exception_type(int vector)729 static int exception_type(int vector)
730 {
731 unsigned int mask;
732
733 if (WARN_ON(vector > 31 || vector == NMI_VECTOR))
734 return EXCPT_INTERRUPT;
735
736 mask = 1 << vector;
737
738 /*
739 * #DBs can be trap-like or fault-like, the caller must check other CPU
740 * state, e.g. DR6, to determine whether a #DB is a trap or fault.
741 */
742 if (mask & (1 << DB_VECTOR))
743 return EXCPT_DB;
744
745 if (mask & ((1 << BP_VECTOR) | (1 << OF_VECTOR)))
746 return EXCPT_TRAP;
747
748 if (mask & ((1 << DF_VECTOR) | (1 << MC_VECTOR)))
749 return EXCPT_ABORT;
750
751 /* Reserved exceptions will result in fault */
752 return EXCPT_FAULT;
753 }
754
kvm_deliver_exception_payload(struct kvm_vcpu * vcpu,struct kvm_queued_exception * ex)755 void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu,
756 struct kvm_queued_exception *ex)
757 {
758 if (!ex->has_payload)
759 return;
760
761 switch (ex->vector) {
762 case DB_VECTOR:
763 /*
764 * "Certain debug exceptions may clear bit 0-3. The
765 * remaining contents of the DR6 register are never
766 * cleared by the processor".
767 */
768 vcpu->arch.dr6 &= ~DR_TRAP_BITS;
769 /*
770 * In order to reflect the #DB exception payload in guest
771 * dr6, three components need to be considered: active low
772 * bit, FIXED_1 bits and active high bits (e.g. DR6_BD,
773 * DR6_BS and DR6_BT)
774 * DR6_ACTIVE_LOW contains the FIXED_1 and active low bits.
775 * In the target guest dr6:
776 * FIXED_1 bits should always be set.
777 * Active low bits should be cleared if 1-setting in payload.
778 * Active high bits should be set if 1-setting in payload.
779 *
780 * Note, the payload is compatible with the pending debug
781 * exceptions/exit qualification under VMX, that active_low bits
782 * are active high in payload.
783 * So they need to be flipped for DR6.
784 */
785 vcpu->arch.dr6 |= DR6_ACTIVE_LOW;
786 vcpu->arch.dr6 |= ex->payload;
787 vcpu->arch.dr6 ^= ex->payload & DR6_ACTIVE_LOW;
788
789 /*
790 * The #DB payload is defined as compatible with the 'pending
791 * debug exceptions' field under VMX, not DR6. While bit 12 is
792 * defined in the 'pending debug exceptions' field (enabled
793 * breakpoint), it is reserved and must be zero in DR6.
794 */
795 vcpu->arch.dr6 &= ~BIT(12);
796 break;
797 case PF_VECTOR:
798 vcpu->arch.cr2 = ex->payload;
799 break;
800 }
801
802 ex->has_payload = false;
803 ex->payload = 0;
804 }
805 EXPORT_SYMBOL_GPL(kvm_deliver_exception_payload);
806
kvm_queue_exception_vmexit(struct kvm_vcpu * vcpu,unsigned int vector,bool has_error_code,u32 error_code,bool has_payload,unsigned long payload)807 static void kvm_queue_exception_vmexit(struct kvm_vcpu *vcpu, unsigned int vector,
808 bool has_error_code, u32 error_code,
809 bool has_payload, unsigned long payload)
810 {
811 struct kvm_queued_exception *ex = &vcpu->arch.exception_vmexit;
812
813 ex->vector = vector;
814 ex->injected = false;
815 ex->pending = true;
816 ex->has_error_code = has_error_code;
817 ex->error_code = error_code;
818 ex->has_payload = has_payload;
819 ex->payload = payload;
820 }
821
kvm_multiple_exception(struct kvm_vcpu * vcpu,unsigned int nr,bool has_error,u32 error_code,bool has_payload,unsigned long payload)822 static void kvm_multiple_exception(struct kvm_vcpu *vcpu, unsigned int nr,
823 bool has_error, u32 error_code,
824 bool has_payload, unsigned long payload)
825 {
826 u32 prev_nr;
827 int class1, class2;
828
829 kvm_make_request(KVM_REQ_EVENT, vcpu);
830
831 /*
832 * If the exception is destined for L2, morph it to a VM-Exit if L1
833 * wants to intercept the exception.
834 */
835 if (is_guest_mode(vcpu) &&
836 kvm_x86_ops.nested_ops->is_exception_vmexit(vcpu, nr, error_code)) {
837 kvm_queue_exception_vmexit(vcpu, nr, has_error, error_code,
838 has_payload, payload);
839 return;
840 }
841
842 if (!vcpu->arch.exception.pending && !vcpu->arch.exception.injected) {
843 queue:
844 vcpu->arch.exception.pending = true;
845 vcpu->arch.exception.injected = false;
846
847 vcpu->arch.exception.has_error_code = has_error;
848 vcpu->arch.exception.vector = nr;
849 vcpu->arch.exception.error_code = error_code;
850 vcpu->arch.exception.has_payload = has_payload;
851 vcpu->arch.exception.payload = payload;
852 if (!is_guest_mode(vcpu))
853 kvm_deliver_exception_payload(vcpu,
854 &vcpu->arch.exception);
855 return;
856 }
857
858 /* to check exception */
859 prev_nr = vcpu->arch.exception.vector;
860 if (prev_nr == DF_VECTOR) {
861 /* triple fault -> shutdown */
862 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
863 return;
864 }
865 class1 = exception_class(prev_nr);
866 class2 = exception_class(nr);
867 if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY) ||
868 (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
869 /*
870 * Synthesize #DF. Clear the previously injected or pending
871 * exception so as not to incorrectly trigger shutdown.
872 */
873 vcpu->arch.exception.injected = false;
874 vcpu->arch.exception.pending = false;
875
876 kvm_queue_exception_e(vcpu, DF_VECTOR, 0);
877 } else {
878 /* replace previous exception with a new one in a hope
879 that instruction re-execution will regenerate lost
880 exception */
881 goto queue;
882 }
883 }
884
kvm_queue_exception(struct kvm_vcpu * vcpu,unsigned nr)885 void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr)
886 {
887 kvm_multiple_exception(vcpu, nr, false, 0, false, 0);
888 }
889 EXPORT_SYMBOL_GPL(kvm_queue_exception);
890
891
kvm_queue_exception_p(struct kvm_vcpu * vcpu,unsigned nr,unsigned long payload)892 void kvm_queue_exception_p(struct kvm_vcpu *vcpu, unsigned nr,
893 unsigned long payload)
894 {
895 kvm_multiple_exception(vcpu, nr, false, 0, true, payload);
896 }
897 EXPORT_SYMBOL_GPL(kvm_queue_exception_p);
898
kvm_queue_exception_e_p(struct kvm_vcpu * vcpu,unsigned nr,u32 error_code,unsigned long payload)899 static void kvm_queue_exception_e_p(struct kvm_vcpu *vcpu, unsigned nr,
900 u32 error_code, unsigned long payload)
901 {
902 kvm_multiple_exception(vcpu, nr, true, error_code, true, payload);
903 }
904
kvm_requeue_exception(struct kvm_vcpu * vcpu,unsigned int nr,bool has_error_code,u32 error_code)905 void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned int nr,
906 bool has_error_code, u32 error_code)
907 {
908
909 /*
910 * On VM-Entry, an exception can be pending if and only if event
911 * injection was blocked by nested_run_pending. In that case, however,
912 * vcpu_enter_guest() requests an immediate exit, and the guest
913 * shouldn't proceed far enough to need reinjection.
914 */
915 WARN_ON_ONCE(kvm_is_exception_pending(vcpu));
916
917 /*
918 * Do not check for interception when injecting an event for L2, as the
919 * exception was checked for intercept when it was original queued, and
920 * re-checking is incorrect if _L1_ injected the exception, in which
921 * case it's exempt from interception.
922 */
923 kvm_make_request(KVM_REQ_EVENT, vcpu);
924
925 vcpu->arch.exception.injected = true;
926 vcpu->arch.exception.has_error_code = has_error_code;
927 vcpu->arch.exception.vector = nr;
928 vcpu->arch.exception.error_code = error_code;
929 vcpu->arch.exception.has_payload = false;
930 vcpu->arch.exception.payload = 0;
931 }
932 EXPORT_SYMBOL_GPL(kvm_requeue_exception);
933
kvm_complete_insn_gp(struct kvm_vcpu * vcpu,int err)934 int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err)
935 {
936 if (err)
937 kvm_inject_gp(vcpu, 0);
938 else
939 return kvm_skip_emulated_instruction(vcpu);
940
941 return 1;
942 }
943 EXPORT_SYMBOL_GPL(kvm_complete_insn_gp);
944
complete_emulated_insn_gp(struct kvm_vcpu * vcpu,int err)945 static int complete_emulated_insn_gp(struct kvm_vcpu *vcpu, int err)
946 {
947 if (err) {
948 kvm_inject_gp(vcpu, 0);
949 return 1;
950 }
951
952 return kvm_emulate_instruction(vcpu, EMULTYPE_NO_DECODE | EMULTYPE_SKIP |
953 EMULTYPE_COMPLETE_USER_EXIT);
954 }
955
kvm_inject_page_fault(struct kvm_vcpu * vcpu,struct x86_exception * fault)956 void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault)
957 {
958 ++vcpu->stat.pf_guest;
959
960 /*
961 * Async #PF in L2 is always forwarded to L1 as a VM-Exit regardless of
962 * whether or not L1 wants to intercept "regular" #PF.
963 */
964 if (is_guest_mode(vcpu) && fault->async_page_fault)
965 kvm_queue_exception_vmexit(vcpu, PF_VECTOR,
966 true, fault->error_code,
967 true, fault->address);
968 else
969 kvm_queue_exception_e_p(vcpu, PF_VECTOR, fault->error_code,
970 fault->address);
971 }
972
kvm_inject_emulated_page_fault(struct kvm_vcpu * vcpu,struct x86_exception * fault)973 void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu,
974 struct x86_exception *fault)
975 {
976 struct kvm_mmu *fault_mmu;
977 WARN_ON_ONCE(fault->vector != PF_VECTOR);
978
979 fault_mmu = fault->nested_page_fault ? vcpu->arch.mmu :
980 vcpu->arch.walk_mmu;
981
982 /*
983 * Invalidate the TLB entry for the faulting address, if it exists,
984 * else the access will fault indefinitely (and to emulate hardware).
985 */
986 if ((fault->error_code & PFERR_PRESENT_MASK) &&
987 !(fault->error_code & PFERR_RSVD_MASK))
988 kvm_mmu_invalidate_addr(vcpu, fault_mmu, fault->address,
989 KVM_MMU_ROOT_CURRENT);
990
991 fault_mmu->inject_page_fault(vcpu, fault);
992 }
993 EXPORT_SYMBOL_GPL(kvm_inject_emulated_page_fault);
994
kvm_inject_nmi(struct kvm_vcpu * vcpu)995 void kvm_inject_nmi(struct kvm_vcpu *vcpu)
996 {
997 atomic_inc(&vcpu->arch.nmi_queued);
998 kvm_make_request(KVM_REQ_NMI, vcpu);
999 }
1000
kvm_queue_exception_e(struct kvm_vcpu * vcpu,unsigned nr,u32 error_code)1001 void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code)
1002 {
1003 kvm_multiple_exception(vcpu, nr, true, error_code, false, 0);
1004 }
1005 EXPORT_SYMBOL_GPL(kvm_queue_exception_e);
1006
1007 /*
1008 * Checks if cpl <= required_cpl; if true, return true. Otherwise queue
1009 * a #GP and return false.
1010 */
kvm_require_cpl(struct kvm_vcpu * vcpu,int required_cpl)1011 bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl)
1012 {
1013 if (kvm_x86_call(get_cpl)(vcpu) <= required_cpl)
1014 return true;
1015 kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
1016 return false;
1017 }
1018
kvm_require_dr(struct kvm_vcpu * vcpu,int dr)1019 bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr)
1020 {
1021 if ((dr != 4 && dr != 5) || !kvm_is_cr4_bit_set(vcpu, X86_CR4_DE))
1022 return true;
1023
1024 kvm_queue_exception(vcpu, UD_VECTOR);
1025 return false;
1026 }
1027 EXPORT_SYMBOL_GPL(kvm_require_dr);
1028
pdptr_rsvd_bits(struct kvm_vcpu * vcpu)1029 static inline u64 pdptr_rsvd_bits(struct kvm_vcpu *vcpu)
1030 {
1031 return vcpu->arch.reserved_gpa_bits | rsvd_bits(5, 8) | rsvd_bits(1, 2);
1032 }
1033
1034 /*
1035 * Load the pae pdptrs. Return 1 if they are all valid, 0 otherwise.
1036 */
load_pdptrs(struct kvm_vcpu * vcpu,unsigned long cr3)1037 int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3)
1038 {
1039 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
1040 gfn_t pdpt_gfn = cr3 >> PAGE_SHIFT;
1041 gpa_t real_gpa;
1042 int i;
1043 int ret;
1044 u64 pdpte[ARRAY_SIZE(mmu->pdptrs)];
1045
1046 /*
1047 * If the MMU is nested, CR3 holds an L2 GPA and needs to be translated
1048 * to an L1 GPA.
1049 */
1050 real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(pdpt_gfn),
1051 PFERR_USER_MASK | PFERR_WRITE_MASK, NULL);
1052 if (real_gpa == INVALID_GPA)
1053 return 0;
1054
1055 /* Note the offset, PDPTRs are 32 byte aligned when using PAE paging. */
1056 ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(real_gpa), pdpte,
1057 cr3 & GENMASK(11, 5), sizeof(pdpte));
1058 if (ret < 0)
1059 return 0;
1060
1061 for (i = 0; i < ARRAY_SIZE(pdpte); ++i) {
1062 if ((pdpte[i] & PT_PRESENT_MASK) &&
1063 (pdpte[i] & pdptr_rsvd_bits(vcpu))) {
1064 return 0;
1065 }
1066 }
1067
1068 /*
1069 * Marking VCPU_EXREG_PDPTR dirty doesn't work for !tdp_enabled.
1070 * Shadow page roots need to be reconstructed instead.
1071 */
1072 if (!tdp_enabled && memcmp(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs)))
1073 kvm_mmu_free_roots(vcpu->kvm, mmu, KVM_MMU_ROOT_CURRENT);
1074
1075 memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs));
1076 kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR);
1077 kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu);
1078 vcpu->arch.pdptrs_from_userspace = false;
1079
1080 return 1;
1081 }
1082 EXPORT_SYMBOL_GPL(load_pdptrs);
1083
kvm_is_valid_cr0(struct kvm_vcpu * vcpu,unsigned long cr0)1084 static bool kvm_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
1085 {
1086 #ifdef CONFIG_X86_64
1087 if (cr0 & 0xffffffff00000000UL)
1088 return false;
1089 #endif
1090
1091 if ((cr0 & X86_CR0_NW) && !(cr0 & X86_CR0_CD))
1092 return false;
1093
1094 if ((cr0 & X86_CR0_PG) && !(cr0 & X86_CR0_PE))
1095 return false;
1096
1097 return kvm_x86_call(is_valid_cr0)(vcpu, cr0);
1098 }
1099
kvm_post_set_cr0(struct kvm_vcpu * vcpu,unsigned long old_cr0,unsigned long cr0)1100 void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned long cr0)
1101 {
1102 /*
1103 * CR0.WP is incorporated into the MMU role, but only for non-nested,
1104 * indirect shadow MMUs. If paging is disabled, no updates are needed
1105 * as there are no permission bits to emulate. If TDP is enabled, the
1106 * MMU's metadata needs to be updated, e.g. so that emulating guest
1107 * translations does the right thing, but there's no need to unload the
1108 * root as CR0.WP doesn't affect SPTEs.
1109 */
1110 if ((cr0 ^ old_cr0) == X86_CR0_WP) {
1111 if (!(cr0 & X86_CR0_PG))
1112 return;
1113
1114 if (tdp_enabled) {
1115 kvm_init_mmu(vcpu);
1116 return;
1117 }
1118 }
1119
1120 if ((cr0 ^ old_cr0) & X86_CR0_PG) {
1121 kvm_clear_async_pf_completion_queue(vcpu);
1122 kvm_async_pf_hash_reset(vcpu);
1123
1124 /*
1125 * Clearing CR0.PG is defined to flush the TLB from the guest's
1126 * perspective.
1127 */
1128 if (!(cr0 & X86_CR0_PG))
1129 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
1130 }
1131
1132 if ((cr0 ^ old_cr0) & KVM_MMU_CR0_ROLE_BITS)
1133 kvm_mmu_reset_context(vcpu);
1134 }
1135 EXPORT_SYMBOL_GPL(kvm_post_set_cr0);
1136
kvm_set_cr0(struct kvm_vcpu * vcpu,unsigned long cr0)1137 int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
1138 {
1139 unsigned long old_cr0 = kvm_read_cr0(vcpu);
1140
1141 if (!kvm_is_valid_cr0(vcpu, cr0))
1142 return 1;
1143
1144 cr0 |= X86_CR0_ET;
1145
1146 /* Write to CR0 reserved bits are ignored, even on Intel. */
1147 cr0 &= ~CR0_RESERVED_BITS;
1148
1149 #ifdef CONFIG_X86_64
1150 if ((vcpu->arch.efer & EFER_LME) && !is_paging(vcpu) &&
1151 (cr0 & X86_CR0_PG)) {
1152 int cs_db, cs_l;
1153
1154 if (!is_pae(vcpu))
1155 return 1;
1156 kvm_x86_call(get_cs_db_l_bits)(vcpu, &cs_db, &cs_l);
1157 if (cs_l)
1158 return 1;
1159 }
1160 #endif
1161 if (!(vcpu->arch.efer & EFER_LME) && (cr0 & X86_CR0_PG) &&
1162 is_pae(vcpu) && ((cr0 ^ old_cr0) & X86_CR0_PDPTR_BITS) &&
1163 !load_pdptrs(vcpu, kvm_read_cr3(vcpu)))
1164 return 1;
1165
1166 if (!(cr0 & X86_CR0_PG) &&
1167 (is_64_bit_mode(vcpu) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)))
1168 return 1;
1169
1170 kvm_x86_call(set_cr0)(vcpu, cr0);
1171
1172 kvm_post_set_cr0(vcpu, old_cr0, cr0);
1173
1174 return 0;
1175 }
1176 EXPORT_SYMBOL_GPL(kvm_set_cr0);
1177
kvm_lmsw(struct kvm_vcpu * vcpu,unsigned long msw)1178 void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
1179 {
1180 (void)kvm_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~0x0eul) | (msw & 0x0f));
1181 }
1182 EXPORT_SYMBOL_GPL(kvm_lmsw);
1183
kvm_load_guest_xsave_state(struct kvm_vcpu * vcpu)1184 void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu)
1185 {
1186 if (vcpu->arch.guest_state_protected)
1187 return;
1188
1189 if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
1190
1191 if (vcpu->arch.xcr0 != kvm_host.xcr0)
1192 xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0);
1193
1194 if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) &&
1195 vcpu->arch.ia32_xss != kvm_host.xss)
1196 wrmsrq(MSR_IA32_XSS, vcpu->arch.ia32_xss);
1197 }
1198
1199 if (cpu_feature_enabled(X86_FEATURE_PKU) &&
1200 vcpu->arch.pkru != vcpu->arch.host_pkru &&
1201 ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) ||
1202 kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE)))
1203 wrpkru(vcpu->arch.pkru);
1204 }
1205 EXPORT_SYMBOL_GPL(kvm_load_guest_xsave_state);
1206
kvm_load_host_xsave_state(struct kvm_vcpu * vcpu)1207 void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu)
1208 {
1209 if (vcpu->arch.guest_state_protected)
1210 return;
1211
1212 if (cpu_feature_enabled(X86_FEATURE_PKU) &&
1213 ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) ||
1214 kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) {
1215 vcpu->arch.pkru = rdpkru();
1216 if (vcpu->arch.pkru != vcpu->arch.host_pkru)
1217 wrpkru(vcpu->arch.host_pkru);
1218 }
1219
1220 if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
1221
1222 if (vcpu->arch.xcr0 != kvm_host.xcr0)
1223 xsetbv(XCR_XFEATURE_ENABLED_MASK, kvm_host.xcr0);
1224
1225 if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) &&
1226 vcpu->arch.ia32_xss != kvm_host.xss)
1227 wrmsrq(MSR_IA32_XSS, kvm_host.xss);
1228 }
1229
1230 }
1231 EXPORT_SYMBOL_GPL(kvm_load_host_xsave_state);
1232
1233 #ifdef CONFIG_X86_64
kvm_guest_supported_xfd(struct kvm_vcpu * vcpu)1234 static inline u64 kvm_guest_supported_xfd(struct kvm_vcpu *vcpu)
1235 {
1236 return vcpu->arch.guest_supported_xcr0 & XFEATURE_MASK_USER_DYNAMIC;
1237 }
1238 #endif
1239
__kvm_set_xcr(struct kvm_vcpu * vcpu,u32 index,u64 xcr)1240 static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
1241 {
1242 u64 xcr0 = xcr;
1243 u64 old_xcr0 = vcpu->arch.xcr0;
1244 u64 valid_bits;
1245
1246 /* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now */
1247 if (index != XCR_XFEATURE_ENABLED_MASK)
1248 return 1;
1249 if (!(xcr0 & XFEATURE_MASK_FP))
1250 return 1;
1251 if ((xcr0 & XFEATURE_MASK_YMM) && !(xcr0 & XFEATURE_MASK_SSE))
1252 return 1;
1253
1254 /*
1255 * Do not allow the guest to set bits that we do not support
1256 * saving. However, xcr0 bit 0 is always set, even if the
1257 * emulated CPU does not support XSAVE (see kvm_vcpu_reset()).
1258 */
1259 valid_bits = vcpu->arch.guest_supported_xcr0 | XFEATURE_MASK_FP;
1260 if (xcr0 & ~valid_bits)
1261 return 1;
1262
1263 if ((!(xcr0 & XFEATURE_MASK_BNDREGS)) !=
1264 (!(xcr0 & XFEATURE_MASK_BNDCSR)))
1265 return 1;
1266
1267 if (xcr0 & XFEATURE_MASK_AVX512) {
1268 if (!(xcr0 & XFEATURE_MASK_YMM))
1269 return 1;
1270 if ((xcr0 & XFEATURE_MASK_AVX512) != XFEATURE_MASK_AVX512)
1271 return 1;
1272 }
1273
1274 if ((xcr0 & XFEATURE_MASK_XTILE) &&
1275 ((xcr0 & XFEATURE_MASK_XTILE) != XFEATURE_MASK_XTILE))
1276 return 1;
1277
1278 vcpu->arch.xcr0 = xcr0;
1279
1280 if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND)
1281 vcpu->arch.cpuid_dynamic_bits_dirty = true;
1282 return 0;
1283 }
1284
kvm_emulate_xsetbv(struct kvm_vcpu * vcpu)1285 int kvm_emulate_xsetbv(struct kvm_vcpu *vcpu)
1286 {
1287 /* Note, #UD due to CR4.OSXSAVE=0 has priority over the intercept. */
1288 if (kvm_x86_call(get_cpl)(vcpu) != 0 ||
1289 __kvm_set_xcr(vcpu, kvm_rcx_read(vcpu), kvm_read_edx_eax(vcpu))) {
1290 kvm_inject_gp(vcpu, 0);
1291 return 1;
1292 }
1293
1294 return kvm_skip_emulated_instruction(vcpu);
1295 }
1296 EXPORT_SYMBOL_GPL(kvm_emulate_xsetbv);
1297
kvm_is_valid_cr4(struct kvm_vcpu * vcpu,unsigned long cr4)1298 static bool kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
1299 {
1300 return __kvm_is_valid_cr4(vcpu, cr4) &&
1301 kvm_x86_call(is_valid_cr4)(vcpu, cr4);
1302 }
1303
kvm_post_set_cr4(struct kvm_vcpu * vcpu,unsigned long old_cr4,unsigned long cr4)1304 void kvm_post_set_cr4(struct kvm_vcpu *vcpu, unsigned long old_cr4, unsigned long cr4)
1305 {
1306 if ((cr4 ^ old_cr4) & KVM_MMU_CR4_ROLE_BITS)
1307 kvm_mmu_reset_context(vcpu);
1308
1309 /*
1310 * If CR4.PCIDE is changed 0 -> 1, there is no need to flush the TLB
1311 * according to the SDM; however, stale prev_roots could be reused
1312 * incorrectly in the future after a MOV to CR3 with NOFLUSH=1, so we
1313 * free them all. This is *not* a superset of KVM_REQ_TLB_FLUSH_GUEST
1314 * or KVM_REQ_TLB_FLUSH_CURRENT, because the hardware TLB is not flushed,
1315 * so fall through.
1316 */
1317 if (!tdp_enabled &&
1318 (cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE))
1319 kvm_mmu_unload(vcpu);
1320
1321 /*
1322 * The TLB has to be flushed for all PCIDs if any of the following
1323 * (architecturally required) changes happen:
1324 * - CR4.PCIDE is changed from 1 to 0
1325 * - CR4.PGE is toggled
1326 *
1327 * This is a superset of KVM_REQ_TLB_FLUSH_CURRENT.
1328 */
1329 if (((cr4 ^ old_cr4) & X86_CR4_PGE) ||
1330 (!(cr4 & X86_CR4_PCIDE) && (old_cr4 & X86_CR4_PCIDE)))
1331 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
1332
1333 /*
1334 * The TLB has to be flushed for the current PCID if any of the
1335 * following (architecturally required) changes happen:
1336 * - CR4.SMEP is changed from 0 to 1
1337 * - CR4.PAE is toggled
1338 */
1339 else if (((cr4 ^ old_cr4) & X86_CR4_PAE) ||
1340 ((cr4 & X86_CR4_SMEP) && !(old_cr4 & X86_CR4_SMEP)))
1341 kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
1342
1343 }
1344 EXPORT_SYMBOL_GPL(kvm_post_set_cr4);
1345
kvm_set_cr4(struct kvm_vcpu * vcpu,unsigned long cr4)1346 int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
1347 {
1348 unsigned long old_cr4 = kvm_read_cr4(vcpu);
1349
1350 if (!kvm_is_valid_cr4(vcpu, cr4))
1351 return 1;
1352
1353 if (is_long_mode(vcpu)) {
1354 if (!(cr4 & X86_CR4_PAE))
1355 return 1;
1356 if ((cr4 ^ old_cr4) & X86_CR4_LA57)
1357 return 1;
1358 } else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
1359 && ((cr4 ^ old_cr4) & X86_CR4_PDPTR_BITS)
1360 && !load_pdptrs(vcpu, kvm_read_cr3(vcpu)))
1361 return 1;
1362
1363 if ((cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) {
1364 /* PCID can not be enabled when cr3[11:0]!=000H or EFER.LMA=0 */
1365 if ((kvm_read_cr3(vcpu) & X86_CR3_PCID_MASK) || !is_long_mode(vcpu))
1366 return 1;
1367 }
1368
1369 kvm_x86_call(set_cr4)(vcpu, cr4);
1370
1371 kvm_post_set_cr4(vcpu, old_cr4, cr4);
1372
1373 return 0;
1374 }
1375 EXPORT_SYMBOL_GPL(kvm_set_cr4);
1376
kvm_invalidate_pcid(struct kvm_vcpu * vcpu,unsigned long pcid)1377 static void kvm_invalidate_pcid(struct kvm_vcpu *vcpu, unsigned long pcid)
1378 {
1379 struct kvm_mmu *mmu = vcpu->arch.mmu;
1380 unsigned long roots_to_free = 0;
1381 int i;
1382
1383 /*
1384 * MOV CR3 and INVPCID are usually not intercepted when using TDP, but
1385 * this is reachable when running EPT=1 and unrestricted_guest=0, and
1386 * also via the emulator. KVM's TDP page tables are not in the scope of
1387 * the invalidation, but the guest's TLB entries need to be flushed as
1388 * the CPU may have cached entries in its TLB for the target PCID.
1389 */
1390 if (unlikely(tdp_enabled)) {
1391 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
1392 return;
1393 }
1394
1395 /*
1396 * If neither the current CR3 nor any of the prev_roots use the given
1397 * PCID, then nothing needs to be done here because a resync will
1398 * happen anyway before switching to any other CR3.
1399 */
1400 if (kvm_get_active_pcid(vcpu) == pcid) {
1401 kvm_make_request(KVM_REQ_MMU_SYNC, vcpu);
1402 kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
1403 }
1404
1405 /*
1406 * If PCID is disabled, there is no need to free prev_roots even if the
1407 * PCIDs for them are also 0, because MOV to CR3 always flushes the TLB
1408 * with PCIDE=0.
1409 */
1410 if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE))
1411 return;
1412
1413 for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
1414 if (kvm_get_pcid(vcpu, mmu->prev_roots[i].pgd) == pcid)
1415 roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
1416
1417 kvm_mmu_free_roots(vcpu->kvm, mmu, roots_to_free);
1418 }
1419
kvm_set_cr3(struct kvm_vcpu * vcpu,unsigned long cr3)1420 int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
1421 {
1422 bool skip_tlb_flush = false;
1423 unsigned long pcid = 0;
1424 #ifdef CONFIG_X86_64
1425 if (kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)) {
1426 skip_tlb_flush = cr3 & X86_CR3_PCID_NOFLUSH;
1427 cr3 &= ~X86_CR3_PCID_NOFLUSH;
1428 pcid = cr3 & X86_CR3_PCID_MASK;
1429 }
1430 #endif
1431
1432 /* PDPTRs are always reloaded for PAE paging. */
1433 if (cr3 == kvm_read_cr3(vcpu) && !is_pae_paging(vcpu))
1434 goto handle_tlb_flush;
1435
1436 /*
1437 * Do not condition the GPA check on long mode, this helper is used to
1438 * stuff CR3, e.g. for RSM emulation, and there is no guarantee that
1439 * the current vCPU mode is accurate.
1440 */
1441 if (!kvm_vcpu_is_legal_cr3(vcpu, cr3))
1442 return 1;
1443
1444 if (is_pae_paging(vcpu) && !load_pdptrs(vcpu, cr3))
1445 return 1;
1446
1447 if (cr3 != kvm_read_cr3(vcpu))
1448 kvm_mmu_new_pgd(vcpu, cr3);
1449
1450 vcpu->arch.cr3 = cr3;
1451 kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
1452 /* Do not call post_set_cr3, we do not get here for confidential guests. */
1453
1454 handle_tlb_flush:
1455 /*
1456 * A load of CR3 that flushes the TLB flushes only the current PCID,
1457 * even if PCID is disabled, in which case PCID=0 is flushed. It's a
1458 * moot point in the end because _disabling_ PCID will flush all PCIDs,
1459 * and it's impossible to use a non-zero PCID when PCID is disabled,
1460 * i.e. only PCID=0 can be relevant.
1461 */
1462 if (!skip_tlb_flush)
1463 kvm_invalidate_pcid(vcpu, pcid);
1464
1465 return 0;
1466 }
1467 EXPORT_SYMBOL_GPL(kvm_set_cr3);
1468
kvm_set_cr8(struct kvm_vcpu * vcpu,unsigned long cr8)1469 int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8)
1470 {
1471 if (cr8 & CR8_RESERVED_BITS)
1472 return 1;
1473 if (lapic_in_kernel(vcpu))
1474 kvm_lapic_set_tpr(vcpu, cr8);
1475 else
1476 vcpu->arch.cr8 = cr8;
1477 return 0;
1478 }
1479 EXPORT_SYMBOL_GPL(kvm_set_cr8);
1480
kvm_get_cr8(struct kvm_vcpu * vcpu)1481 unsigned long kvm_get_cr8(struct kvm_vcpu *vcpu)
1482 {
1483 if (lapic_in_kernel(vcpu))
1484 return kvm_lapic_get_cr8(vcpu);
1485 else
1486 return vcpu->arch.cr8;
1487 }
1488 EXPORT_SYMBOL_GPL(kvm_get_cr8);
1489
kvm_update_dr0123(struct kvm_vcpu * vcpu)1490 static void kvm_update_dr0123(struct kvm_vcpu *vcpu)
1491 {
1492 int i;
1493
1494 if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)) {
1495 for (i = 0; i < KVM_NR_DB_REGS; i++)
1496 vcpu->arch.eff_db[i] = vcpu->arch.db[i];
1497 }
1498 }
1499
kvm_update_dr7(struct kvm_vcpu * vcpu)1500 void kvm_update_dr7(struct kvm_vcpu *vcpu)
1501 {
1502 unsigned long dr7;
1503
1504 if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)
1505 dr7 = vcpu->arch.guest_debug_dr7;
1506 else
1507 dr7 = vcpu->arch.dr7;
1508 kvm_x86_call(set_dr7)(vcpu, dr7);
1509 vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_BP_ENABLED;
1510 if (dr7 & DR7_BP_EN_MASK)
1511 vcpu->arch.switch_db_regs |= KVM_DEBUGREG_BP_ENABLED;
1512 }
1513 EXPORT_SYMBOL_GPL(kvm_update_dr7);
1514
kvm_dr6_fixed(struct kvm_vcpu * vcpu)1515 static u64 kvm_dr6_fixed(struct kvm_vcpu *vcpu)
1516 {
1517 u64 fixed = DR6_FIXED_1;
1518
1519 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_RTM))
1520 fixed |= DR6_RTM;
1521
1522 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_BUS_LOCK_DETECT))
1523 fixed |= DR6_BUS_LOCK;
1524 return fixed;
1525 }
1526
kvm_set_dr(struct kvm_vcpu * vcpu,int dr,unsigned long val)1527 int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val)
1528 {
1529 size_t size = ARRAY_SIZE(vcpu->arch.db);
1530
1531 switch (dr) {
1532 case 0 ... 3:
1533 vcpu->arch.db[array_index_nospec(dr, size)] = val;
1534 if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP))
1535 vcpu->arch.eff_db[dr] = val;
1536 break;
1537 case 4:
1538 case 6:
1539 if (!kvm_dr6_valid(val))
1540 return 1; /* #GP */
1541 vcpu->arch.dr6 = (val & DR6_VOLATILE) | kvm_dr6_fixed(vcpu);
1542 break;
1543 case 5:
1544 default: /* 7 */
1545 if (!kvm_dr7_valid(val))
1546 return 1; /* #GP */
1547 vcpu->arch.dr7 = (val & DR7_VOLATILE) | DR7_FIXED_1;
1548 kvm_update_dr7(vcpu);
1549 break;
1550 }
1551
1552 return 0;
1553 }
1554 EXPORT_SYMBOL_GPL(kvm_set_dr);
1555
kvm_get_dr(struct kvm_vcpu * vcpu,int dr)1556 unsigned long kvm_get_dr(struct kvm_vcpu *vcpu, int dr)
1557 {
1558 size_t size = ARRAY_SIZE(vcpu->arch.db);
1559
1560 switch (dr) {
1561 case 0 ... 3:
1562 return vcpu->arch.db[array_index_nospec(dr, size)];
1563 case 4:
1564 case 6:
1565 return vcpu->arch.dr6;
1566 case 5:
1567 default: /* 7 */
1568 return vcpu->arch.dr7;
1569 }
1570 }
1571 EXPORT_SYMBOL_GPL(kvm_get_dr);
1572
kvm_emulate_rdpmc(struct kvm_vcpu * vcpu)1573 int kvm_emulate_rdpmc(struct kvm_vcpu *vcpu)
1574 {
1575 u32 ecx = kvm_rcx_read(vcpu);
1576 u64 data;
1577
1578 if (kvm_pmu_rdpmc(vcpu, ecx, &data)) {
1579 kvm_inject_gp(vcpu, 0);
1580 return 1;
1581 }
1582
1583 kvm_rax_write(vcpu, (u32)data);
1584 kvm_rdx_write(vcpu, data >> 32);
1585 return kvm_skip_emulated_instruction(vcpu);
1586 }
1587 EXPORT_SYMBOL_GPL(kvm_emulate_rdpmc);
1588
1589 /*
1590 * Some IA32_ARCH_CAPABILITIES bits have dependencies on MSRs that KVM
1591 * does not yet virtualize. These include:
1592 * 10 - MISC_PACKAGE_CTRLS
1593 * 11 - ENERGY_FILTERING_CTL
1594 * 12 - DOITM
1595 * 18 - FB_CLEAR_CTRL
1596 * 21 - XAPIC_DISABLE_STATUS
1597 * 23 - OVERCLOCKING_STATUS
1598 */
1599
1600 #define KVM_SUPPORTED_ARCH_CAP \
1601 (ARCH_CAP_RDCL_NO | ARCH_CAP_IBRS_ALL | ARCH_CAP_RSBA | \
1602 ARCH_CAP_SKIP_VMENTRY_L1DFLUSH | ARCH_CAP_SSB_NO | ARCH_CAP_MDS_NO | \
1603 ARCH_CAP_PSCHANGE_MC_NO | ARCH_CAP_TSX_CTRL_MSR | ARCH_CAP_TAA_NO | \
1604 ARCH_CAP_SBDR_SSDP_NO | ARCH_CAP_FBSDP_NO | ARCH_CAP_PSDP_NO | \
1605 ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO | \
1606 ARCH_CAP_RFDS_NO | ARCH_CAP_RFDS_CLEAR | ARCH_CAP_BHI_NO | ARCH_CAP_ITS_NO)
1607
kvm_get_arch_capabilities(void)1608 static u64 kvm_get_arch_capabilities(void)
1609 {
1610 u64 data = kvm_host.arch_capabilities & KVM_SUPPORTED_ARCH_CAP;
1611
1612 /*
1613 * If nx_huge_pages is enabled, KVM's shadow paging will ensure that
1614 * the nested hypervisor runs with NX huge pages. If it is not,
1615 * L1 is anyway vulnerable to ITLB_MULTIHIT exploits from other
1616 * L1 guests, so it need not worry about its own (L2) guests.
1617 */
1618 data |= ARCH_CAP_PSCHANGE_MC_NO;
1619
1620 /*
1621 * If we're doing cache flushes (either "always" or "cond")
1622 * we will do one whenever the guest does a vmlaunch/vmresume.
1623 * If an outer hypervisor is doing the cache flush for us
1624 * (ARCH_CAP_SKIP_VMENTRY_L1DFLUSH), we can safely pass that
1625 * capability to the guest too, and if EPT is disabled we're not
1626 * vulnerable. Overall, only VMENTER_L1D_FLUSH_NEVER will
1627 * require a nested hypervisor to do a flush of its own.
1628 */
1629 if (l1tf_vmx_mitigation != VMENTER_L1D_FLUSH_NEVER)
1630 data |= ARCH_CAP_SKIP_VMENTRY_L1DFLUSH;
1631
1632 if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN))
1633 data |= ARCH_CAP_RDCL_NO;
1634 if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
1635 data |= ARCH_CAP_SSB_NO;
1636 if (!boot_cpu_has_bug(X86_BUG_MDS))
1637 data |= ARCH_CAP_MDS_NO;
1638 if (!boot_cpu_has_bug(X86_BUG_RFDS))
1639 data |= ARCH_CAP_RFDS_NO;
1640 if (!boot_cpu_has_bug(X86_BUG_ITS))
1641 data |= ARCH_CAP_ITS_NO;
1642
1643 if (!boot_cpu_has(X86_FEATURE_RTM)) {
1644 /*
1645 * If RTM=0 because the kernel has disabled TSX, the host might
1646 * have TAA_NO or TSX_CTRL. Clear TAA_NO (the guest sees RTM=0
1647 * and therefore knows that there cannot be TAA) but keep
1648 * TSX_CTRL: some buggy userspaces leave it set on tsx=on hosts,
1649 * and we want to allow migrating those guests to tsx=off hosts.
1650 */
1651 data &= ~ARCH_CAP_TAA_NO;
1652 } else if (!boot_cpu_has_bug(X86_BUG_TAA)) {
1653 data |= ARCH_CAP_TAA_NO;
1654 } else {
1655 /*
1656 * Nothing to do here; we emulate TSX_CTRL if present on the
1657 * host so the guest can choose between disabling TSX or
1658 * using VERW to clear CPU buffers.
1659 */
1660 }
1661
1662 if (!boot_cpu_has_bug(X86_BUG_GDS) || gds_ucode_mitigated())
1663 data |= ARCH_CAP_GDS_NO;
1664
1665 return data;
1666 }
1667
kvm_get_feature_msr(struct kvm_vcpu * vcpu,u32 index,u64 * data,bool host_initiated)1668 static int kvm_get_feature_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data,
1669 bool host_initiated)
1670 {
1671 WARN_ON_ONCE(!host_initiated);
1672
1673 switch (index) {
1674 case MSR_IA32_ARCH_CAPABILITIES:
1675 *data = kvm_get_arch_capabilities();
1676 break;
1677 case MSR_IA32_PERF_CAPABILITIES:
1678 *data = kvm_caps.supported_perf_cap;
1679 break;
1680 case MSR_PLATFORM_INFO:
1681 *data = MSR_PLATFORM_INFO_CPUID_FAULT;
1682 break;
1683 case MSR_IA32_UCODE_REV:
1684 rdmsrq_safe(index, data);
1685 break;
1686 default:
1687 return kvm_x86_call(get_feature_msr)(index, data);
1688 }
1689 return 0;
1690 }
1691
do_get_feature_msr(struct kvm_vcpu * vcpu,unsigned index,u64 * data)1692 static int do_get_feature_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
1693 {
1694 return kvm_do_msr_access(vcpu, index, data, true, MSR_TYPE_R,
1695 kvm_get_feature_msr);
1696 }
1697
__kvm_valid_efer(struct kvm_vcpu * vcpu,u64 efer)1698 static bool __kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)
1699 {
1700 if (efer & EFER_AUTOIBRS && !guest_cpu_cap_has(vcpu, X86_FEATURE_AUTOIBRS))
1701 return false;
1702
1703 if (efer & EFER_FFXSR && !guest_cpu_cap_has(vcpu, X86_FEATURE_FXSR_OPT))
1704 return false;
1705
1706 if (efer & EFER_SVME && !guest_cpu_cap_has(vcpu, X86_FEATURE_SVM))
1707 return false;
1708
1709 if (efer & (EFER_LME | EFER_LMA) &&
1710 !guest_cpu_cap_has(vcpu, X86_FEATURE_LM))
1711 return false;
1712
1713 if (efer & EFER_NX && !guest_cpu_cap_has(vcpu, X86_FEATURE_NX))
1714 return false;
1715
1716 return true;
1717
1718 }
kvm_valid_efer(struct kvm_vcpu * vcpu,u64 efer)1719 bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)
1720 {
1721 if (efer & efer_reserved_bits)
1722 return false;
1723
1724 return __kvm_valid_efer(vcpu, efer);
1725 }
1726 EXPORT_SYMBOL_GPL(kvm_valid_efer);
1727
set_efer(struct kvm_vcpu * vcpu,struct msr_data * msr_info)1728 static int set_efer(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
1729 {
1730 u64 old_efer = vcpu->arch.efer;
1731 u64 efer = msr_info->data;
1732 int r;
1733
1734 if (efer & efer_reserved_bits)
1735 return 1;
1736
1737 if (!msr_info->host_initiated) {
1738 if (!__kvm_valid_efer(vcpu, efer))
1739 return 1;
1740
1741 if (is_paging(vcpu) &&
1742 (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME))
1743 return 1;
1744 }
1745
1746 efer &= ~EFER_LMA;
1747 efer |= vcpu->arch.efer & EFER_LMA;
1748
1749 r = kvm_x86_call(set_efer)(vcpu, efer);
1750 if (r) {
1751 WARN_ON(r > 0);
1752 return r;
1753 }
1754
1755 if ((efer ^ old_efer) & KVM_MMU_EFER_ROLE_BITS)
1756 kvm_mmu_reset_context(vcpu);
1757
1758 if (!static_cpu_has(X86_FEATURE_XSAVES) &&
1759 (efer & EFER_SVME))
1760 kvm_hv_xsaves_xsavec_maybe_warn(vcpu);
1761
1762 return 0;
1763 }
1764
kvm_enable_efer_bits(u64 mask)1765 void kvm_enable_efer_bits(u64 mask)
1766 {
1767 efer_reserved_bits &= ~mask;
1768 }
1769 EXPORT_SYMBOL_GPL(kvm_enable_efer_bits);
1770
kvm_msr_allowed(struct kvm_vcpu * vcpu,u32 index,u32 type)1771 bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type)
1772 {
1773 struct kvm_x86_msr_filter *msr_filter;
1774 struct msr_bitmap_range *ranges;
1775 struct kvm *kvm = vcpu->kvm;
1776 bool allowed;
1777 int idx;
1778 u32 i;
1779
1780 /* x2APIC MSRs do not support filtering. */
1781 if (index >= 0x800 && index <= 0x8ff)
1782 return true;
1783
1784 idx = srcu_read_lock(&kvm->srcu);
1785
1786 msr_filter = srcu_dereference(kvm->arch.msr_filter, &kvm->srcu);
1787 if (!msr_filter) {
1788 allowed = true;
1789 goto out;
1790 }
1791
1792 allowed = msr_filter->default_allow;
1793 ranges = msr_filter->ranges;
1794
1795 for (i = 0; i < msr_filter->count; i++) {
1796 u32 start = ranges[i].base;
1797 u32 end = start + ranges[i].nmsrs;
1798 u32 flags = ranges[i].flags;
1799 unsigned long *bitmap = ranges[i].bitmap;
1800
1801 if ((index >= start) && (index < end) && (flags & type)) {
1802 allowed = test_bit(index - start, bitmap);
1803 break;
1804 }
1805 }
1806
1807 out:
1808 srcu_read_unlock(&kvm->srcu, idx);
1809
1810 return allowed;
1811 }
1812 EXPORT_SYMBOL_GPL(kvm_msr_allowed);
1813
1814 /*
1815 * Write @data into the MSR specified by @index. Select MSR specific fault
1816 * checks are bypassed if @host_initiated is %true.
1817 * Returns 0 on success, non-0 otherwise.
1818 * Assumes vcpu_load() was already called.
1819 */
__kvm_set_msr(struct kvm_vcpu * vcpu,u32 index,u64 data,bool host_initiated)1820 static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data,
1821 bool host_initiated)
1822 {
1823 struct msr_data msr;
1824
1825 switch (index) {
1826 case MSR_FS_BASE:
1827 case MSR_GS_BASE:
1828 case MSR_KERNEL_GS_BASE:
1829 case MSR_CSTAR:
1830 case MSR_LSTAR:
1831 if (is_noncanonical_msr_address(data, vcpu))
1832 return 1;
1833 break;
1834 case MSR_IA32_SYSENTER_EIP:
1835 case MSR_IA32_SYSENTER_ESP:
1836 /*
1837 * IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if
1838 * non-canonical address is written on Intel but not on
1839 * AMD (which ignores the top 32-bits, because it does
1840 * not implement 64-bit SYSENTER).
1841 *
1842 * 64-bit code should hence be able to write a non-canonical
1843 * value on AMD. Making the address canonical ensures that
1844 * vmentry does not fail on Intel after writing a non-canonical
1845 * value, and that something deterministic happens if the guest
1846 * invokes 64-bit SYSENTER.
1847 */
1848 data = __canonical_address(data, max_host_virt_addr_bits());
1849 break;
1850 case MSR_TSC_AUX:
1851 if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX))
1852 return 1;
1853
1854 if (!host_initiated &&
1855 !guest_cpu_cap_has(vcpu, X86_FEATURE_RDTSCP) &&
1856 !guest_cpu_cap_has(vcpu, X86_FEATURE_RDPID))
1857 return 1;
1858
1859 /*
1860 * Per Intel's SDM, bits 63:32 are reserved, but AMD's APM has
1861 * incomplete and conflicting architectural behavior. Current
1862 * AMD CPUs completely ignore bits 63:32, i.e. they aren't
1863 * reserved and always read as zeros. Enforce Intel's reserved
1864 * bits check if the guest CPU is Intel compatible, otherwise
1865 * clear the bits. This ensures cross-vendor migration will
1866 * provide consistent behavior for the guest.
1867 */
1868 if (guest_cpuid_is_intel_compatible(vcpu) && (data >> 32) != 0)
1869 return 1;
1870
1871 data = (u32)data;
1872 break;
1873 }
1874
1875 msr.data = data;
1876 msr.index = index;
1877 msr.host_initiated = host_initiated;
1878
1879 return kvm_x86_call(set_msr)(vcpu, &msr);
1880 }
1881
_kvm_set_msr(struct kvm_vcpu * vcpu,u32 index,u64 * data,bool host_initiated)1882 static int _kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data,
1883 bool host_initiated)
1884 {
1885 return __kvm_set_msr(vcpu, index, *data, host_initiated);
1886 }
1887
kvm_set_msr_ignored_check(struct kvm_vcpu * vcpu,u32 index,u64 data,bool host_initiated)1888 static int kvm_set_msr_ignored_check(struct kvm_vcpu *vcpu,
1889 u32 index, u64 data, bool host_initiated)
1890 {
1891 return kvm_do_msr_access(vcpu, index, &data, host_initiated, MSR_TYPE_W,
1892 _kvm_set_msr);
1893 }
1894
1895 /*
1896 * Read the MSR specified by @index into @data. Select MSR specific fault
1897 * checks are bypassed if @host_initiated is %true.
1898 * Returns 0 on success, non-0 otherwise.
1899 * Assumes vcpu_load() was already called.
1900 */
__kvm_get_msr(struct kvm_vcpu * vcpu,u32 index,u64 * data,bool host_initiated)1901 int __kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data,
1902 bool host_initiated)
1903 {
1904 struct msr_data msr;
1905 int ret;
1906
1907 switch (index) {
1908 case MSR_TSC_AUX:
1909 if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX))
1910 return 1;
1911
1912 if (!host_initiated &&
1913 !guest_cpu_cap_has(vcpu, X86_FEATURE_RDTSCP) &&
1914 !guest_cpu_cap_has(vcpu, X86_FEATURE_RDPID))
1915 return 1;
1916 break;
1917 }
1918
1919 msr.index = index;
1920 msr.host_initiated = host_initiated;
1921
1922 ret = kvm_x86_call(get_msr)(vcpu, &msr);
1923 if (!ret)
1924 *data = msr.data;
1925 return ret;
1926 }
1927
kvm_get_msr_ignored_check(struct kvm_vcpu * vcpu,u32 index,u64 * data,bool host_initiated)1928 static int kvm_get_msr_ignored_check(struct kvm_vcpu *vcpu,
1929 u32 index, u64 *data, bool host_initiated)
1930 {
1931 return kvm_do_msr_access(vcpu, index, data, host_initiated, MSR_TYPE_R,
1932 __kvm_get_msr);
1933 }
1934
kvm_get_msr_with_filter(struct kvm_vcpu * vcpu,u32 index,u64 * data)1935 int kvm_get_msr_with_filter(struct kvm_vcpu *vcpu, u32 index, u64 *data)
1936 {
1937 if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_READ))
1938 return KVM_MSR_RET_FILTERED;
1939 return kvm_get_msr_ignored_check(vcpu, index, data, false);
1940 }
1941 EXPORT_SYMBOL_GPL(kvm_get_msr_with_filter);
1942
kvm_set_msr_with_filter(struct kvm_vcpu * vcpu,u32 index,u64 data)1943 int kvm_set_msr_with_filter(struct kvm_vcpu *vcpu, u32 index, u64 data)
1944 {
1945 if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_WRITE))
1946 return KVM_MSR_RET_FILTERED;
1947 return kvm_set_msr_ignored_check(vcpu, index, data, false);
1948 }
1949 EXPORT_SYMBOL_GPL(kvm_set_msr_with_filter);
1950
kvm_get_msr(struct kvm_vcpu * vcpu,u32 index,u64 * data)1951 int kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data)
1952 {
1953 return kvm_get_msr_ignored_check(vcpu, index, data, false);
1954 }
1955 EXPORT_SYMBOL_GPL(kvm_get_msr);
1956
kvm_set_msr(struct kvm_vcpu * vcpu,u32 index,u64 data)1957 int kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data)
1958 {
1959 return kvm_set_msr_ignored_check(vcpu, index, data, false);
1960 }
1961 EXPORT_SYMBOL_GPL(kvm_set_msr);
1962
complete_userspace_rdmsr(struct kvm_vcpu * vcpu)1963 static void complete_userspace_rdmsr(struct kvm_vcpu *vcpu)
1964 {
1965 if (!vcpu->run->msr.error) {
1966 kvm_rax_write(vcpu, (u32)vcpu->run->msr.data);
1967 kvm_rdx_write(vcpu, vcpu->run->msr.data >> 32);
1968 }
1969 }
1970
complete_emulated_msr_access(struct kvm_vcpu * vcpu)1971 static int complete_emulated_msr_access(struct kvm_vcpu *vcpu)
1972 {
1973 return complete_emulated_insn_gp(vcpu, vcpu->run->msr.error);
1974 }
1975
complete_emulated_rdmsr(struct kvm_vcpu * vcpu)1976 static int complete_emulated_rdmsr(struct kvm_vcpu *vcpu)
1977 {
1978 complete_userspace_rdmsr(vcpu);
1979 return complete_emulated_msr_access(vcpu);
1980 }
1981
complete_fast_msr_access(struct kvm_vcpu * vcpu)1982 static int complete_fast_msr_access(struct kvm_vcpu *vcpu)
1983 {
1984 return kvm_x86_call(complete_emulated_msr)(vcpu, vcpu->run->msr.error);
1985 }
1986
complete_fast_rdmsr(struct kvm_vcpu * vcpu)1987 static int complete_fast_rdmsr(struct kvm_vcpu *vcpu)
1988 {
1989 complete_userspace_rdmsr(vcpu);
1990 return complete_fast_msr_access(vcpu);
1991 }
1992
kvm_msr_reason(int r)1993 static u64 kvm_msr_reason(int r)
1994 {
1995 switch (r) {
1996 case KVM_MSR_RET_UNSUPPORTED:
1997 return KVM_MSR_EXIT_REASON_UNKNOWN;
1998 case KVM_MSR_RET_FILTERED:
1999 return KVM_MSR_EXIT_REASON_FILTER;
2000 default:
2001 return KVM_MSR_EXIT_REASON_INVAL;
2002 }
2003 }
2004
kvm_msr_user_space(struct kvm_vcpu * vcpu,u32 index,u32 exit_reason,u64 data,int (* completion)(struct kvm_vcpu * vcpu),int r)2005 static int kvm_msr_user_space(struct kvm_vcpu *vcpu, u32 index,
2006 u32 exit_reason, u64 data,
2007 int (*completion)(struct kvm_vcpu *vcpu),
2008 int r)
2009 {
2010 u64 msr_reason = kvm_msr_reason(r);
2011
2012 /* Check if the user wanted to know about this MSR fault */
2013 if (!(vcpu->kvm->arch.user_space_msr_mask & msr_reason))
2014 return 0;
2015
2016 vcpu->run->exit_reason = exit_reason;
2017 vcpu->run->msr.error = 0;
2018 memset(vcpu->run->msr.pad, 0, sizeof(vcpu->run->msr.pad));
2019 vcpu->run->msr.reason = msr_reason;
2020 vcpu->run->msr.index = index;
2021 vcpu->run->msr.data = data;
2022 vcpu->arch.complete_userspace_io = completion;
2023
2024 return 1;
2025 }
2026
kvm_emulate_rdmsr(struct kvm_vcpu * vcpu)2027 int kvm_emulate_rdmsr(struct kvm_vcpu *vcpu)
2028 {
2029 u32 ecx = kvm_rcx_read(vcpu);
2030 u64 data;
2031 int r;
2032
2033 r = kvm_get_msr_with_filter(vcpu, ecx, &data);
2034
2035 if (!r) {
2036 trace_kvm_msr_read(ecx, data);
2037
2038 kvm_rax_write(vcpu, data & -1u);
2039 kvm_rdx_write(vcpu, (data >> 32) & -1u);
2040 } else {
2041 /* MSR read failed? See if we should ask user space */
2042 if (kvm_msr_user_space(vcpu, ecx, KVM_EXIT_X86_RDMSR, 0,
2043 complete_fast_rdmsr, r))
2044 return 0;
2045 trace_kvm_msr_read_ex(ecx);
2046 }
2047
2048 return kvm_x86_call(complete_emulated_msr)(vcpu, r);
2049 }
2050 EXPORT_SYMBOL_GPL(kvm_emulate_rdmsr);
2051
kvm_emulate_wrmsr(struct kvm_vcpu * vcpu)2052 int kvm_emulate_wrmsr(struct kvm_vcpu *vcpu)
2053 {
2054 u32 ecx = kvm_rcx_read(vcpu);
2055 u64 data = kvm_read_edx_eax(vcpu);
2056 int r;
2057
2058 r = kvm_set_msr_with_filter(vcpu, ecx, data);
2059
2060 if (!r) {
2061 trace_kvm_msr_write(ecx, data);
2062 } else {
2063 /* MSR write failed? See if we should ask user space */
2064 if (kvm_msr_user_space(vcpu, ecx, KVM_EXIT_X86_WRMSR, data,
2065 complete_fast_msr_access, r))
2066 return 0;
2067 /* Signal all other negative errors to userspace */
2068 if (r < 0)
2069 return r;
2070 trace_kvm_msr_write_ex(ecx, data);
2071 }
2072
2073 return kvm_x86_call(complete_emulated_msr)(vcpu, r);
2074 }
2075 EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr);
2076
kvm_emulate_as_nop(struct kvm_vcpu * vcpu)2077 int kvm_emulate_as_nop(struct kvm_vcpu *vcpu)
2078 {
2079 return kvm_skip_emulated_instruction(vcpu);
2080 }
2081
kvm_emulate_invd(struct kvm_vcpu * vcpu)2082 int kvm_emulate_invd(struct kvm_vcpu *vcpu)
2083 {
2084 /* Treat an INVD instruction as a NOP and just skip it. */
2085 return kvm_emulate_as_nop(vcpu);
2086 }
2087 EXPORT_SYMBOL_GPL(kvm_emulate_invd);
2088
kvm_handle_invalid_op(struct kvm_vcpu * vcpu)2089 int kvm_handle_invalid_op(struct kvm_vcpu *vcpu)
2090 {
2091 kvm_queue_exception(vcpu, UD_VECTOR);
2092 return 1;
2093 }
2094 EXPORT_SYMBOL_GPL(kvm_handle_invalid_op);
2095
2096
kvm_emulate_monitor_mwait(struct kvm_vcpu * vcpu,const char * insn)2097 static int kvm_emulate_monitor_mwait(struct kvm_vcpu *vcpu, const char *insn)
2098 {
2099 bool enabled;
2100
2101 if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS))
2102 goto emulate_as_nop;
2103
2104 if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT))
2105 enabled = guest_cpu_cap_has(vcpu, X86_FEATURE_MWAIT);
2106 else
2107 enabled = vcpu->arch.ia32_misc_enable_msr & MSR_IA32_MISC_ENABLE_MWAIT;
2108
2109 if (!enabled)
2110 return kvm_handle_invalid_op(vcpu);
2111
2112 emulate_as_nop:
2113 pr_warn_once("%s instruction emulated as NOP!\n", insn);
2114 return kvm_emulate_as_nop(vcpu);
2115 }
kvm_emulate_mwait(struct kvm_vcpu * vcpu)2116 int kvm_emulate_mwait(struct kvm_vcpu *vcpu)
2117 {
2118 return kvm_emulate_monitor_mwait(vcpu, "MWAIT");
2119 }
2120 EXPORT_SYMBOL_GPL(kvm_emulate_mwait);
2121
kvm_emulate_monitor(struct kvm_vcpu * vcpu)2122 int kvm_emulate_monitor(struct kvm_vcpu *vcpu)
2123 {
2124 return kvm_emulate_monitor_mwait(vcpu, "MONITOR");
2125 }
2126 EXPORT_SYMBOL_GPL(kvm_emulate_monitor);
2127
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu)2128 static inline bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)
2129 {
2130 xfer_to_guest_mode_prepare();
2131
2132 return READ_ONCE(vcpu->mode) == EXITING_GUEST_MODE ||
2133 kvm_request_pending(vcpu) || xfer_to_guest_mode_work_pending();
2134 }
2135
2136 /*
2137 * The fast path for frequent and performance sensitive wrmsr emulation,
2138 * i.e. the sending of IPI, sending IPI early in the VM-Exit flow reduces
2139 * the latency of virtual IPI by avoiding the expensive bits of transitioning
2140 * from guest to host, e.g. reacquiring KVM's SRCU lock. In contrast to the
2141 * other cases which must be called after interrupts are enabled on the host.
2142 */
handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu * vcpu,u64 data)2143 static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data)
2144 {
2145 if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(vcpu->arch.apic))
2146 return 1;
2147
2148 if (((data & APIC_SHORT_MASK) == APIC_DEST_NOSHORT) &&
2149 ((data & APIC_DEST_MASK) == APIC_DEST_PHYSICAL) &&
2150 ((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
2151 ((u32)(data >> 32) != X2APIC_BROADCAST))
2152 return kvm_x2apic_icr_write(vcpu->arch.apic, data);
2153
2154 return 1;
2155 }
2156
handle_fastpath_set_tscdeadline(struct kvm_vcpu * vcpu,u64 data)2157 static int handle_fastpath_set_tscdeadline(struct kvm_vcpu *vcpu, u64 data)
2158 {
2159 if (!kvm_can_use_hv_timer(vcpu))
2160 return 1;
2161
2162 kvm_set_lapic_tscdeadline_msr(vcpu, data);
2163 return 0;
2164 }
2165
handle_fastpath_set_msr_irqoff(struct kvm_vcpu * vcpu)2166 fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu)
2167 {
2168 u32 msr = kvm_rcx_read(vcpu);
2169 u64 data;
2170 fastpath_t ret;
2171 bool handled;
2172
2173 kvm_vcpu_srcu_read_lock(vcpu);
2174
2175 switch (msr) {
2176 case APIC_BASE_MSR + (APIC_ICR >> 4):
2177 data = kvm_read_edx_eax(vcpu);
2178 handled = !handle_fastpath_set_x2apic_icr_irqoff(vcpu, data);
2179 break;
2180 case MSR_IA32_TSC_DEADLINE:
2181 data = kvm_read_edx_eax(vcpu);
2182 handled = !handle_fastpath_set_tscdeadline(vcpu, data);
2183 break;
2184 default:
2185 handled = false;
2186 break;
2187 }
2188
2189 if (handled) {
2190 if (!kvm_skip_emulated_instruction(vcpu))
2191 ret = EXIT_FASTPATH_EXIT_USERSPACE;
2192 else
2193 ret = EXIT_FASTPATH_REENTER_GUEST;
2194 trace_kvm_msr_write(msr, data);
2195 } else {
2196 ret = EXIT_FASTPATH_NONE;
2197 }
2198
2199 kvm_vcpu_srcu_read_unlock(vcpu);
2200
2201 return ret;
2202 }
2203 EXPORT_SYMBOL_GPL(handle_fastpath_set_msr_irqoff);
2204
2205 /*
2206 * Adapt set_msr() to msr_io()'s calling convention
2207 */
do_get_msr(struct kvm_vcpu * vcpu,unsigned index,u64 * data)2208 static int do_get_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
2209 {
2210 return kvm_get_msr_ignored_check(vcpu, index, data, true);
2211 }
2212
do_set_msr(struct kvm_vcpu * vcpu,unsigned index,u64 * data)2213 static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
2214 {
2215 u64 val;
2216
2217 /*
2218 * Disallow writes to immutable feature MSRs after KVM_RUN. KVM does
2219 * not support modifying the guest vCPU model on the fly, e.g. changing
2220 * the nVMX capabilities while L2 is running is nonsensical. Allow
2221 * writes of the same value, e.g. to allow userspace to blindly stuff
2222 * all MSRs when emulating RESET.
2223 */
2224 if (kvm_vcpu_has_run(vcpu) && kvm_is_immutable_feature_msr(index) &&
2225 (do_get_msr(vcpu, index, &val) || *data != val))
2226 return -EINVAL;
2227
2228 return kvm_set_msr_ignored_check(vcpu, index, *data, true);
2229 }
2230
2231 #ifdef CONFIG_X86_64
2232 struct pvclock_clock {
2233 int vclock_mode;
2234 u64 cycle_last;
2235 u64 mask;
2236 u32 mult;
2237 u32 shift;
2238 u64 base_cycles;
2239 u64 offset;
2240 };
2241
2242 struct pvclock_gtod_data {
2243 seqcount_t seq;
2244
2245 struct pvclock_clock clock; /* extract of a clocksource struct */
2246 struct pvclock_clock raw_clock; /* extract of a clocksource struct */
2247
2248 ktime_t offs_boot;
2249 u64 wall_time_sec;
2250 };
2251
2252 static struct pvclock_gtod_data pvclock_gtod_data;
2253
update_pvclock_gtod(struct timekeeper * tk)2254 static void update_pvclock_gtod(struct timekeeper *tk)
2255 {
2256 struct pvclock_gtod_data *vdata = &pvclock_gtod_data;
2257
2258 write_seqcount_begin(&vdata->seq);
2259
2260 /* copy pvclock gtod data */
2261 vdata->clock.vclock_mode = tk->tkr_mono.clock->vdso_clock_mode;
2262 vdata->clock.cycle_last = tk->tkr_mono.cycle_last;
2263 vdata->clock.mask = tk->tkr_mono.mask;
2264 vdata->clock.mult = tk->tkr_mono.mult;
2265 vdata->clock.shift = tk->tkr_mono.shift;
2266 vdata->clock.base_cycles = tk->tkr_mono.xtime_nsec;
2267 vdata->clock.offset = tk->tkr_mono.base;
2268
2269 vdata->raw_clock.vclock_mode = tk->tkr_raw.clock->vdso_clock_mode;
2270 vdata->raw_clock.cycle_last = tk->tkr_raw.cycle_last;
2271 vdata->raw_clock.mask = tk->tkr_raw.mask;
2272 vdata->raw_clock.mult = tk->tkr_raw.mult;
2273 vdata->raw_clock.shift = tk->tkr_raw.shift;
2274 vdata->raw_clock.base_cycles = tk->tkr_raw.xtime_nsec;
2275 vdata->raw_clock.offset = tk->tkr_raw.base;
2276
2277 vdata->wall_time_sec = tk->xtime_sec;
2278
2279 vdata->offs_boot = tk->offs_boot;
2280
2281 write_seqcount_end(&vdata->seq);
2282 }
2283
get_kvmclock_base_ns(void)2284 static s64 get_kvmclock_base_ns(void)
2285 {
2286 /* Count up from boot time, but with the frequency of the raw clock. */
2287 return ktime_to_ns(ktime_add(ktime_get_raw(), pvclock_gtod_data.offs_boot));
2288 }
2289 #else
get_kvmclock_base_ns(void)2290 static s64 get_kvmclock_base_ns(void)
2291 {
2292 /* Master clock not used, so we can just use CLOCK_BOOTTIME. */
2293 return ktime_get_boottime_ns();
2294 }
2295 #endif
2296
kvm_write_wall_clock(struct kvm * kvm,gpa_t wall_clock,int sec_hi_ofs)2297 static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock, int sec_hi_ofs)
2298 {
2299 int version;
2300 int r;
2301 struct pvclock_wall_clock wc;
2302 u32 wc_sec_hi;
2303 u64 wall_nsec;
2304
2305 if (!wall_clock)
2306 return;
2307
2308 r = kvm_read_guest(kvm, wall_clock, &version, sizeof(version));
2309 if (r)
2310 return;
2311
2312 if (version & 1)
2313 ++version; /* first time write, random junk */
2314
2315 ++version;
2316
2317 if (kvm_write_guest(kvm, wall_clock, &version, sizeof(version)))
2318 return;
2319
2320 wall_nsec = kvm_get_wall_clock_epoch(kvm);
2321
2322 wc.nsec = do_div(wall_nsec, NSEC_PER_SEC);
2323 wc.sec = (u32)wall_nsec; /* overflow in 2106 guest time */
2324 wc.version = version;
2325
2326 kvm_write_guest(kvm, wall_clock, &wc, sizeof(wc));
2327
2328 if (sec_hi_ofs) {
2329 wc_sec_hi = wall_nsec >> 32;
2330 kvm_write_guest(kvm, wall_clock + sec_hi_ofs,
2331 &wc_sec_hi, sizeof(wc_sec_hi));
2332 }
2333
2334 version++;
2335 kvm_write_guest(kvm, wall_clock, &version, sizeof(version));
2336 }
2337
kvm_write_system_time(struct kvm_vcpu * vcpu,gpa_t system_time,bool old_msr,bool host_initiated)2338 static void kvm_write_system_time(struct kvm_vcpu *vcpu, gpa_t system_time,
2339 bool old_msr, bool host_initiated)
2340 {
2341 struct kvm_arch *ka = &vcpu->kvm->arch;
2342
2343 if (vcpu->vcpu_id == 0 && !host_initiated) {
2344 if (ka->boot_vcpu_runs_old_kvmclock != old_msr)
2345 kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
2346
2347 ka->boot_vcpu_runs_old_kvmclock = old_msr;
2348 }
2349
2350 vcpu->arch.time = system_time;
2351 kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
2352
2353 /* we verify if the enable bit is set... */
2354 if (system_time & 1)
2355 kvm_gpc_activate(&vcpu->arch.pv_time, system_time & ~1ULL,
2356 sizeof(struct pvclock_vcpu_time_info));
2357 else
2358 kvm_gpc_deactivate(&vcpu->arch.pv_time);
2359
2360 return;
2361 }
2362
div_frac(uint32_t dividend,uint32_t divisor)2363 static uint32_t div_frac(uint32_t dividend, uint32_t divisor)
2364 {
2365 do_shl32_div32(dividend, divisor);
2366 return dividend;
2367 }
2368
kvm_get_time_scale(uint64_t scaled_hz,uint64_t base_hz,s8 * pshift,u32 * pmultiplier)2369 static void kvm_get_time_scale(uint64_t scaled_hz, uint64_t base_hz,
2370 s8 *pshift, u32 *pmultiplier)
2371 {
2372 uint64_t scaled64;
2373 int32_t shift = 0;
2374 uint64_t tps64;
2375 uint32_t tps32;
2376
2377 tps64 = base_hz;
2378 scaled64 = scaled_hz;
2379 while (tps64 > scaled64*2 || tps64 & 0xffffffff00000000ULL) {
2380 tps64 >>= 1;
2381 shift--;
2382 }
2383
2384 tps32 = (uint32_t)tps64;
2385 while (tps32 <= scaled64 || scaled64 & 0xffffffff00000000ULL) {
2386 if (scaled64 & 0xffffffff00000000ULL || tps32 & 0x80000000)
2387 scaled64 >>= 1;
2388 else
2389 tps32 <<= 1;
2390 shift++;
2391 }
2392
2393 *pshift = shift;
2394 *pmultiplier = div_frac(scaled64, tps32);
2395 }
2396
2397 #ifdef CONFIG_X86_64
2398 static atomic_t kvm_guest_has_master_clock = ATOMIC_INIT(0);
2399 #endif
2400
2401 static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz);
2402 static unsigned long max_tsc_khz;
2403
adjust_tsc_khz(u32 khz,s32 ppm)2404 static u32 adjust_tsc_khz(u32 khz, s32 ppm)
2405 {
2406 u64 v = (u64)khz * (1000000 + ppm);
2407 do_div(v, 1000000);
2408 return v;
2409 }
2410
2411 static void kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 l1_multiplier);
2412
set_tsc_khz(struct kvm_vcpu * vcpu,u32 user_tsc_khz,bool scale)2413 static int set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale)
2414 {
2415 u64 ratio;
2416
2417 /* Guest TSC same frequency as host TSC? */
2418 if (!scale) {
2419 kvm_vcpu_write_tsc_multiplier(vcpu, kvm_caps.default_tsc_scaling_ratio);
2420 return 0;
2421 }
2422
2423 /* TSC scaling supported? */
2424 if (!kvm_caps.has_tsc_control) {
2425 if (user_tsc_khz > tsc_khz) {
2426 vcpu->arch.tsc_catchup = 1;
2427 vcpu->arch.tsc_always_catchup = 1;
2428 return 0;
2429 } else {
2430 pr_warn_ratelimited("user requested TSC rate below hardware speed\n");
2431 return -1;
2432 }
2433 }
2434
2435 /* TSC scaling required - calculate ratio */
2436 ratio = mul_u64_u32_div(1ULL << kvm_caps.tsc_scaling_ratio_frac_bits,
2437 user_tsc_khz, tsc_khz);
2438
2439 if (ratio == 0 || ratio >= kvm_caps.max_tsc_scaling_ratio) {
2440 pr_warn_ratelimited("Invalid TSC scaling ratio - virtual-tsc-khz=%u\n",
2441 user_tsc_khz);
2442 return -1;
2443 }
2444
2445 kvm_vcpu_write_tsc_multiplier(vcpu, ratio);
2446 return 0;
2447 }
2448
kvm_set_tsc_khz(struct kvm_vcpu * vcpu,u32 user_tsc_khz)2449 static int kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
2450 {
2451 u32 thresh_lo, thresh_hi;
2452 int use_scaling = 0;
2453
2454 /* tsc_khz can be zero if TSC calibration fails */
2455 if (user_tsc_khz == 0) {
2456 /* set tsc_scaling_ratio to a safe value */
2457 kvm_vcpu_write_tsc_multiplier(vcpu, kvm_caps.default_tsc_scaling_ratio);
2458 return -1;
2459 }
2460
2461 /* Compute a scale to convert nanoseconds in TSC cycles */
2462 kvm_get_time_scale(user_tsc_khz * 1000LL, NSEC_PER_SEC,
2463 &vcpu->arch.virtual_tsc_shift,
2464 &vcpu->arch.virtual_tsc_mult);
2465 vcpu->arch.virtual_tsc_khz = user_tsc_khz;
2466
2467 /*
2468 * Compute the variation in TSC rate which is acceptable
2469 * within the range of tolerance and decide if the
2470 * rate being applied is within that bounds of the hardware
2471 * rate. If so, no scaling or compensation need be done.
2472 */
2473 thresh_lo = adjust_tsc_khz(tsc_khz, -tsc_tolerance_ppm);
2474 thresh_hi = adjust_tsc_khz(tsc_khz, tsc_tolerance_ppm);
2475 if (user_tsc_khz < thresh_lo || user_tsc_khz > thresh_hi) {
2476 pr_debug("requested TSC rate %u falls outside tolerance [%u,%u]\n",
2477 user_tsc_khz, thresh_lo, thresh_hi);
2478 use_scaling = 1;
2479 }
2480 return set_tsc_khz(vcpu, user_tsc_khz, use_scaling);
2481 }
2482
compute_guest_tsc(struct kvm_vcpu * vcpu,s64 kernel_ns)2483 static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns)
2484 {
2485 u64 tsc = pvclock_scale_delta(kernel_ns-vcpu->arch.this_tsc_nsec,
2486 vcpu->arch.virtual_tsc_mult,
2487 vcpu->arch.virtual_tsc_shift);
2488 tsc += vcpu->arch.this_tsc_write;
2489 return tsc;
2490 }
2491
2492 #ifdef CONFIG_X86_64
gtod_is_based_on_tsc(int mode)2493 static inline bool gtod_is_based_on_tsc(int mode)
2494 {
2495 return mode == VDSO_CLOCKMODE_TSC || mode == VDSO_CLOCKMODE_HVCLOCK;
2496 }
2497 #endif
2498
kvm_track_tsc_matching(struct kvm_vcpu * vcpu,bool new_generation)2499 static void kvm_track_tsc_matching(struct kvm_vcpu *vcpu, bool new_generation)
2500 {
2501 #ifdef CONFIG_X86_64
2502 struct kvm_arch *ka = &vcpu->kvm->arch;
2503 struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2504
2505 /*
2506 * To use the masterclock, the host clocksource must be based on TSC
2507 * and all vCPUs must have matching TSCs. Note, the count for matching
2508 * vCPUs doesn't include the reference vCPU, hence "+1".
2509 */
2510 bool use_master_clock = (ka->nr_vcpus_matched_tsc + 1 ==
2511 atomic_read(&vcpu->kvm->online_vcpus)) &&
2512 gtod_is_based_on_tsc(gtod->clock.vclock_mode);
2513
2514 /*
2515 * Request a masterclock update if the masterclock needs to be toggled
2516 * on/off, or when starting a new generation and the masterclock is
2517 * enabled (compute_guest_tsc() requires the masterclock snapshot to be
2518 * taken _after_ the new generation is created).
2519 */
2520 if ((ka->use_master_clock && new_generation) ||
2521 (ka->use_master_clock != use_master_clock))
2522 kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
2523
2524 trace_kvm_track_tsc(vcpu->vcpu_id, ka->nr_vcpus_matched_tsc,
2525 atomic_read(&vcpu->kvm->online_vcpus),
2526 ka->use_master_clock, gtod->clock.vclock_mode);
2527 #endif
2528 }
2529
2530 /*
2531 * Multiply tsc by a fixed point number represented by ratio.
2532 *
2533 * The most significant 64-N bits (mult) of ratio represent the
2534 * integral part of the fixed point number; the remaining N bits
2535 * (frac) represent the fractional part, ie. ratio represents a fixed
2536 * point number (mult + frac * 2^(-N)).
2537 *
2538 * N equals to kvm_caps.tsc_scaling_ratio_frac_bits.
2539 */
__scale_tsc(u64 ratio,u64 tsc)2540 static inline u64 __scale_tsc(u64 ratio, u64 tsc)
2541 {
2542 return mul_u64_u64_shr(tsc, ratio, kvm_caps.tsc_scaling_ratio_frac_bits);
2543 }
2544
kvm_scale_tsc(u64 tsc,u64 ratio)2545 u64 kvm_scale_tsc(u64 tsc, u64 ratio)
2546 {
2547 u64 _tsc = tsc;
2548
2549 if (ratio != kvm_caps.default_tsc_scaling_ratio)
2550 _tsc = __scale_tsc(ratio, tsc);
2551
2552 return _tsc;
2553 }
2554
kvm_compute_l1_tsc_offset(struct kvm_vcpu * vcpu,u64 target_tsc)2555 static u64 kvm_compute_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
2556 {
2557 u64 tsc;
2558
2559 tsc = kvm_scale_tsc(rdtsc(), vcpu->arch.l1_tsc_scaling_ratio);
2560
2561 return target_tsc - tsc;
2562 }
2563
kvm_read_l1_tsc(struct kvm_vcpu * vcpu,u64 host_tsc)2564 u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc)
2565 {
2566 return vcpu->arch.l1_tsc_offset +
2567 kvm_scale_tsc(host_tsc, vcpu->arch.l1_tsc_scaling_ratio);
2568 }
2569 EXPORT_SYMBOL_GPL(kvm_read_l1_tsc);
2570
kvm_calc_nested_tsc_offset(u64 l1_offset,u64 l2_offset,u64 l2_multiplier)2571 u64 kvm_calc_nested_tsc_offset(u64 l1_offset, u64 l2_offset, u64 l2_multiplier)
2572 {
2573 u64 nested_offset;
2574
2575 if (l2_multiplier == kvm_caps.default_tsc_scaling_ratio)
2576 nested_offset = l1_offset;
2577 else
2578 nested_offset = mul_s64_u64_shr((s64) l1_offset, l2_multiplier,
2579 kvm_caps.tsc_scaling_ratio_frac_bits);
2580
2581 nested_offset += l2_offset;
2582 return nested_offset;
2583 }
2584 EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_offset);
2585
kvm_calc_nested_tsc_multiplier(u64 l1_multiplier,u64 l2_multiplier)2586 u64 kvm_calc_nested_tsc_multiplier(u64 l1_multiplier, u64 l2_multiplier)
2587 {
2588 if (l2_multiplier != kvm_caps.default_tsc_scaling_ratio)
2589 return mul_u64_u64_shr(l1_multiplier, l2_multiplier,
2590 kvm_caps.tsc_scaling_ratio_frac_bits);
2591
2592 return l1_multiplier;
2593 }
2594 EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_multiplier);
2595
kvm_vcpu_write_tsc_offset(struct kvm_vcpu * vcpu,u64 l1_offset)2596 static void kvm_vcpu_write_tsc_offset(struct kvm_vcpu *vcpu, u64 l1_offset)
2597 {
2598 if (vcpu->arch.guest_tsc_protected)
2599 return;
2600
2601 trace_kvm_write_tsc_offset(vcpu->vcpu_id,
2602 vcpu->arch.l1_tsc_offset,
2603 l1_offset);
2604
2605 vcpu->arch.l1_tsc_offset = l1_offset;
2606
2607 /*
2608 * If we are here because L1 chose not to trap WRMSR to TSC then
2609 * according to the spec this should set L1's TSC (as opposed to
2610 * setting L1's offset for L2).
2611 */
2612 if (is_guest_mode(vcpu))
2613 vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset(
2614 l1_offset,
2615 kvm_x86_call(get_l2_tsc_offset)(vcpu),
2616 kvm_x86_call(get_l2_tsc_multiplier)(vcpu));
2617 else
2618 vcpu->arch.tsc_offset = l1_offset;
2619
2620 kvm_x86_call(write_tsc_offset)(vcpu);
2621 }
2622
kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu * vcpu,u64 l1_multiplier)2623 static void kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 l1_multiplier)
2624 {
2625 vcpu->arch.l1_tsc_scaling_ratio = l1_multiplier;
2626
2627 /* Userspace is changing the multiplier while L2 is active */
2628 if (is_guest_mode(vcpu))
2629 vcpu->arch.tsc_scaling_ratio = kvm_calc_nested_tsc_multiplier(
2630 l1_multiplier,
2631 kvm_x86_call(get_l2_tsc_multiplier)(vcpu));
2632 else
2633 vcpu->arch.tsc_scaling_ratio = l1_multiplier;
2634
2635 if (kvm_caps.has_tsc_control)
2636 kvm_x86_call(write_tsc_multiplier)(vcpu);
2637 }
2638
kvm_check_tsc_unstable(void)2639 static inline bool kvm_check_tsc_unstable(void)
2640 {
2641 #ifdef CONFIG_X86_64
2642 /*
2643 * TSC is marked unstable when we're running on Hyper-V,
2644 * 'TSC page' clocksource is good.
2645 */
2646 if (pvclock_gtod_data.clock.vclock_mode == VDSO_CLOCKMODE_HVCLOCK)
2647 return false;
2648 #endif
2649 return check_tsc_unstable();
2650 }
2651
2652 /*
2653 * Infers attempts to synchronize the guest's tsc from host writes. Sets the
2654 * offset for the vcpu and tracks the TSC matching generation that the vcpu
2655 * participates in.
2656 */
__kvm_synchronize_tsc(struct kvm_vcpu * vcpu,u64 offset,u64 tsc,u64 ns,bool matched,bool user_set_tsc)2657 static void __kvm_synchronize_tsc(struct kvm_vcpu *vcpu, u64 offset, u64 tsc,
2658 u64 ns, bool matched, bool user_set_tsc)
2659 {
2660 struct kvm *kvm = vcpu->kvm;
2661
2662 lockdep_assert_held(&kvm->arch.tsc_write_lock);
2663
2664 if (vcpu->arch.guest_tsc_protected)
2665 return;
2666
2667 if (user_set_tsc)
2668 vcpu->kvm->arch.user_set_tsc = true;
2669
2670 /*
2671 * We also track th most recent recorded KHZ, write and time to
2672 * allow the matching interval to be extended at each write.
2673 */
2674 kvm->arch.last_tsc_nsec = ns;
2675 kvm->arch.last_tsc_write = tsc;
2676 kvm->arch.last_tsc_khz = vcpu->arch.virtual_tsc_khz;
2677 kvm->arch.last_tsc_offset = offset;
2678
2679 vcpu->arch.last_guest_tsc = tsc;
2680
2681 kvm_vcpu_write_tsc_offset(vcpu, offset);
2682
2683 if (!matched) {
2684 /*
2685 * We split periods of matched TSC writes into generations.
2686 * For each generation, we track the original measured
2687 * nanosecond time, offset, and write, so if TSCs are in
2688 * sync, we can match exact offset, and if not, we can match
2689 * exact software computation in compute_guest_tsc()
2690 *
2691 * These values are tracked in kvm->arch.cur_xxx variables.
2692 */
2693 kvm->arch.cur_tsc_generation++;
2694 kvm->arch.cur_tsc_nsec = ns;
2695 kvm->arch.cur_tsc_write = tsc;
2696 kvm->arch.cur_tsc_offset = offset;
2697 kvm->arch.nr_vcpus_matched_tsc = 0;
2698 } else if (vcpu->arch.this_tsc_generation != kvm->arch.cur_tsc_generation) {
2699 kvm->arch.nr_vcpus_matched_tsc++;
2700 }
2701
2702 /* Keep track of which generation this VCPU has synchronized to */
2703 vcpu->arch.this_tsc_generation = kvm->arch.cur_tsc_generation;
2704 vcpu->arch.this_tsc_nsec = kvm->arch.cur_tsc_nsec;
2705 vcpu->arch.this_tsc_write = kvm->arch.cur_tsc_write;
2706
2707 kvm_track_tsc_matching(vcpu, !matched);
2708 }
2709
kvm_synchronize_tsc(struct kvm_vcpu * vcpu,u64 * user_value)2710 static void kvm_synchronize_tsc(struct kvm_vcpu *vcpu, u64 *user_value)
2711 {
2712 u64 data = user_value ? *user_value : 0;
2713 struct kvm *kvm = vcpu->kvm;
2714 u64 offset, ns, elapsed;
2715 unsigned long flags;
2716 bool matched = false;
2717 bool synchronizing = false;
2718
2719 raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
2720 offset = kvm_compute_l1_tsc_offset(vcpu, data);
2721 ns = get_kvmclock_base_ns();
2722 elapsed = ns - kvm->arch.last_tsc_nsec;
2723
2724 if (vcpu->arch.virtual_tsc_khz) {
2725 if (data == 0) {
2726 /*
2727 * Force synchronization when creating a vCPU, or when
2728 * userspace explicitly writes a zero value.
2729 */
2730 synchronizing = true;
2731 } else if (kvm->arch.user_set_tsc) {
2732 u64 tsc_exp = kvm->arch.last_tsc_write +
2733 nsec_to_cycles(vcpu, elapsed);
2734 u64 tsc_hz = vcpu->arch.virtual_tsc_khz * 1000LL;
2735 /*
2736 * Here lies UAPI baggage: when a user-initiated TSC write has
2737 * a small delta (1 second) of virtual cycle time against the
2738 * previously set vCPU, we assume that they were intended to be
2739 * in sync and the delta was only due to the racy nature of the
2740 * legacy API.
2741 *
2742 * This trick falls down when restoring a guest which genuinely
2743 * has been running for less time than the 1 second of imprecision
2744 * which we allow for in the legacy API. In this case, the first
2745 * value written by userspace (on any vCPU) should not be subject
2746 * to this 'correction' to make it sync up with values that only
2747 * come from the kernel's default vCPU creation. Make the 1-second
2748 * slop hack only trigger if the user_set_tsc flag is already set.
2749 */
2750 synchronizing = data < tsc_exp + tsc_hz &&
2751 data + tsc_hz > tsc_exp;
2752 }
2753 }
2754
2755
2756 /*
2757 * For a reliable TSC, we can match TSC offsets, and for an unstable
2758 * TSC, we add elapsed time in this computation. We could let the
2759 * compensation code attempt to catch up if we fall behind, but
2760 * it's better to try to match offsets from the beginning.
2761 */
2762 if (synchronizing &&
2763 vcpu->arch.virtual_tsc_khz == kvm->arch.last_tsc_khz) {
2764 if (!kvm_check_tsc_unstable()) {
2765 offset = kvm->arch.cur_tsc_offset;
2766 } else {
2767 u64 delta = nsec_to_cycles(vcpu, elapsed);
2768 data += delta;
2769 offset = kvm_compute_l1_tsc_offset(vcpu, data);
2770 }
2771 matched = true;
2772 }
2773
2774 __kvm_synchronize_tsc(vcpu, offset, data, ns, matched, !!user_value);
2775 raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
2776 }
2777
adjust_tsc_offset_guest(struct kvm_vcpu * vcpu,s64 adjustment)2778 static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu,
2779 s64 adjustment)
2780 {
2781 u64 tsc_offset = vcpu->arch.l1_tsc_offset;
2782 kvm_vcpu_write_tsc_offset(vcpu, tsc_offset + adjustment);
2783 }
2784
adjust_tsc_offset_host(struct kvm_vcpu * vcpu,s64 adjustment)2785 static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment)
2786 {
2787 if (vcpu->arch.l1_tsc_scaling_ratio != kvm_caps.default_tsc_scaling_ratio)
2788 WARN_ON(adjustment < 0);
2789 adjustment = kvm_scale_tsc((u64) adjustment,
2790 vcpu->arch.l1_tsc_scaling_ratio);
2791 adjust_tsc_offset_guest(vcpu, adjustment);
2792 }
2793
2794 #ifdef CONFIG_X86_64
2795
read_tsc(void)2796 static u64 read_tsc(void)
2797 {
2798 u64 ret = (u64)rdtsc_ordered();
2799 u64 last = pvclock_gtod_data.clock.cycle_last;
2800
2801 if (likely(ret >= last))
2802 return ret;
2803
2804 /*
2805 * GCC likes to generate cmov here, but this branch is extremely
2806 * predictable (it's just a function of time and the likely is
2807 * very likely) and there's a data dependence, so force GCC
2808 * to generate a branch instead. I don't barrier() because
2809 * we don't actually need a barrier, and if this function
2810 * ever gets inlined it will generate worse code.
2811 */
2812 asm volatile ("");
2813 return last;
2814 }
2815
vgettsc(struct pvclock_clock * clock,u64 * tsc_timestamp,int * mode)2816 static inline u64 vgettsc(struct pvclock_clock *clock, u64 *tsc_timestamp,
2817 int *mode)
2818 {
2819 u64 tsc_pg_val;
2820 long v;
2821
2822 switch (clock->vclock_mode) {
2823 case VDSO_CLOCKMODE_HVCLOCK:
2824 if (hv_read_tsc_page_tsc(hv_get_tsc_page(),
2825 tsc_timestamp, &tsc_pg_val)) {
2826 /* TSC page valid */
2827 *mode = VDSO_CLOCKMODE_HVCLOCK;
2828 v = (tsc_pg_val - clock->cycle_last) &
2829 clock->mask;
2830 } else {
2831 /* TSC page invalid */
2832 *mode = VDSO_CLOCKMODE_NONE;
2833 }
2834 break;
2835 case VDSO_CLOCKMODE_TSC:
2836 *mode = VDSO_CLOCKMODE_TSC;
2837 *tsc_timestamp = read_tsc();
2838 v = (*tsc_timestamp - clock->cycle_last) &
2839 clock->mask;
2840 break;
2841 default:
2842 *mode = VDSO_CLOCKMODE_NONE;
2843 }
2844
2845 if (*mode == VDSO_CLOCKMODE_NONE)
2846 *tsc_timestamp = v = 0;
2847
2848 return v * clock->mult;
2849 }
2850
2851 /*
2852 * As with get_kvmclock_base_ns(), this counts from boot time, at the
2853 * frequency of CLOCK_MONOTONIC_RAW (hence adding gtos->offs_boot).
2854 */
do_kvmclock_base(s64 * t,u64 * tsc_timestamp)2855 static int do_kvmclock_base(s64 *t, u64 *tsc_timestamp)
2856 {
2857 struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2858 unsigned long seq;
2859 int mode;
2860 u64 ns;
2861
2862 do {
2863 seq = read_seqcount_begin(>od->seq);
2864 ns = gtod->raw_clock.base_cycles;
2865 ns += vgettsc(>od->raw_clock, tsc_timestamp, &mode);
2866 ns >>= gtod->raw_clock.shift;
2867 ns += ktime_to_ns(ktime_add(gtod->raw_clock.offset, gtod->offs_boot));
2868 } while (unlikely(read_seqcount_retry(>od->seq, seq)));
2869 *t = ns;
2870
2871 return mode;
2872 }
2873
2874 /*
2875 * This calculates CLOCK_MONOTONIC at the time of the TSC snapshot, with
2876 * no boot time offset.
2877 */
do_monotonic(s64 * t,u64 * tsc_timestamp)2878 static int do_monotonic(s64 *t, u64 *tsc_timestamp)
2879 {
2880 struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2881 unsigned long seq;
2882 int mode;
2883 u64 ns;
2884
2885 do {
2886 seq = read_seqcount_begin(>od->seq);
2887 ns = gtod->clock.base_cycles;
2888 ns += vgettsc(>od->clock, tsc_timestamp, &mode);
2889 ns >>= gtod->clock.shift;
2890 ns += ktime_to_ns(gtod->clock.offset);
2891 } while (unlikely(read_seqcount_retry(>od->seq, seq)));
2892 *t = ns;
2893
2894 return mode;
2895 }
2896
do_realtime(struct timespec64 * ts,u64 * tsc_timestamp)2897 static int do_realtime(struct timespec64 *ts, u64 *tsc_timestamp)
2898 {
2899 struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2900 unsigned long seq;
2901 int mode;
2902 u64 ns;
2903
2904 do {
2905 seq = read_seqcount_begin(>od->seq);
2906 ts->tv_sec = gtod->wall_time_sec;
2907 ns = gtod->clock.base_cycles;
2908 ns += vgettsc(>od->clock, tsc_timestamp, &mode);
2909 ns >>= gtod->clock.shift;
2910 } while (unlikely(read_seqcount_retry(>od->seq, seq)));
2911
2912 ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
2913 ts->tv_nsec = ns;
2914
2915 return mode;
2916 }
2917
2918 /*
2919 * Calculates the kvmclock_base_ns (CLOCK_MONOTONIC_RAW + boot time) and
2920 * reports the TSC value from which it do so. Returns true if host is
2921 * using TSC based clocksource.
2922 */
kvm_get_time_and_clockread(s64 * kernel_ns,u64 * tsc_timestamp)2923 static bool kvm_get_time_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp)
2924 {
2925 /* checked again under seqlock below */
2926 if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
2927 return false;
2928
2929 return gtod_is_based_on_tsc(do_kvmclock_base(kernel_ns,
2930 tsc_timestamp));
2931 }
2932
2933 /*
2934 * Calculates CLOCK_MONOTONIC and reports the TSC value from which it did
2935 * so. Returns true if host is using TSC based clocksource.
2936 */
kvm_get_monotonic_and_clockread(s64 * kernel_ns,u64 * tsc_timestamp)2937 bool kvm_get_monotonic_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp)
2938 {
2939 /* checked again under seqlock below */
2940 if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
2941 return false;
2942
2943 return gtod_is_based_on_tsc(do_monotonic(kernel_ns,
2944 tsc_timestamp));
2945 }
2946
2947 /*
2948 * Calculates CLOCK_REALTIME and reports the TSC value from which it did
2949 * so. Returns true if host is using TSC based clocksource.
2950 *
2951 * DO NOT USE this for anything related to migration. You want CLOCK_TAI
2952 * for that.
2953 */
kvm_get_walltime_and_clockread(struct timespec64 * ts,u64 * tsc_timestamp)2954 static bool kvm_get_walltime_and_clockread(struct timespec64 *ts,
2955 u64 *tsc_timestamp)
2956 {
2957 /* checked again under seqlock below */
2958 if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
2959 return false;
2960
2961 return gtod_is_based_on_tsc(do_realtime(ts, tsc_timestamp));
2962 }
2963 #endif
2964
2965 /*
2966 *
2967 * Assuming a stable TSC across physical CPUS, and a stable TSC
2968 * across virtual CPUs, the following condition is possible.
2969 * Each numbered line represents an event visible to both
2970 * CPUs at the next numbered event.
2971 *
2972 * "timespecX" represents host monotonic time. "tscX" represents
2973 * RDTSC value.
2974 *
2975 * VCPU0 on CPU0 | VCPU1 on CPU1
2976 *
2977 * 1. read timespec0,tsc0
2978 * 2. | timespec1 = timespec0 + N
2979 * | tsc1 = tsc0 + M
2980 * 3. transition to guest | transition to guest
2981 * 4. ret0 = timespec0 + (rdtsc - tsc0) |
2982 * 5. | ret1 = timespec1 + (rdtsc - tsc1)
2983 * | ret1 = timespec0 + N + (rdtsc - (tsc0 + M))
2984 *
2985 * Since ret0 update is visible to VCPU1 at time 5, to obey monotonicity:
2986 *
2987 * - ret0 < ret1
2988 * - timespec0 + (rdtsc - tsc0) < timespec0 + N + (rdtsc - (tsc0 + M))
2989 * ...
2990 * - 0 < N - M => M < N
2991 *
2992 * That is, when timespec0 != timespec1, M < N. Unfortunately that is not
2993 * always the case (the difference between two distinct xtime instances
2994 * might be smaller then the difference between corresponding TSC reads,
2995 * when updating guest vcpus pvclock areas).
2996 *
2997 * To avoid that problem, do not allow visibility of distinct
2998 * system_timestamp/tsc_timestamp values simultaneously: use a master
2999 * copy of host monotonic time values. Update that master copy
3000 * in lockstep.
3001 *
3002 * Rely on synchronization of host TSCs and guest TSCs for monotonicity.
3003 *
3004 */
3005
pvclock_update_vm_gtod_copy(struct kvm * kvm)3006 static void pvclock_update_vm_gtod_copy(struct kvm *kvm)
3007 {
3008 #ifdef CONFIG_X86_64
3009 struct kvm_arch *ka = &kvm->arch;
3010 int vclock_mode;
3011 bool host_tsc_clocksource, vcpus_matched;
3012
3013 lockdep_assert_held(&kvm->arch.tsc_write_lock);
3014 vcpus_matched = (ka->nr_vcpus_matched_tsc + 1 ==
3015 atomic_read(&kvm->online_vcpus));
3016
3017 /*
3018 * If the host uses TSC clock, then passthrough TSC as stable
3019 * to the guest.
3020 */
3021 host_tsc_clocksource = kvm_get_time_and_clockread(
3022 &ka->master_kernel_ns,
3023 &ka->master_cycle_now);
3024
3025 ka->use_master_clock = host_tsc_clocksource && vcpus_matched
3026 && !ka->backwards_tsc_observed
3027 && !ka->boot_vcpu_runs_old_kvmclock;
3028
3029 if (ka->use_master_clock)
3030 atomic_set(&kvm_guest_has_master_clock, 1);
3031
3032 vclock_mode = pvclock_gtod_data.clock.vclock_mode;
3033 trace_kvm_update_master_clock(ka->use_master_clock, vclock_mode,
3034 vcpus_matched);
3035 #endif
3036 }
3037
kvm_make_mclock_inprogress_request(struct kvm * kvm)3038 static void kvm_make_mclock_inprogress_request(struct kvm *kvm)
3039 {
3040 kvm_make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
3041 }
3042
__kvm_start_pvclock_update(struct kvm * kvm)3043 static void __kvm_start_pvclock_update(struct kvm *kvm)
3044 {
3045 raw_spin_lock_irq(&kvm->arch.tsc_write_lock);
3046 write_seqcount_begin(&kvm->arch.pvclock_sc);
3047 }
3048
kvm_start_pvclock_update(struct kvm * kvm)3049 static void kvm_start_pvclock_update(struct kvm *kvm)
3050 {
3051 kvm_make_mclock_inprogress_request(kvm);
3052
3053 /* no guest entries from this point */
3054 __kvm_start_pvclock_update(kvm);
3055 }
3056
kvm_end_pvclock_update(struct kvm * kvm)3057 static void kvm_end_pvclock_update(struct kvm *kvm)
3058 {
3059 struct kvm_arch *ka = &kvm->arch;
3060 struct kvm_vcpu *vcpu;
3061 unsigned long i;
3062
3063 write_seqcount_end(&ka->pvclock_sc);
3064 raw_spin_unlock_irq(&ka->tsc_write_lock);
3065 kvm_for_each_vcpu(i, vcpu, kvm)
3066 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
3067
3068 /* guest entries allowed */
3069 kvm_for_each_vcpu(i, vcpu, kvm)
3070 kvm_clear_request(KVM_REQ_MCLOCK_INPROGRESS, vcpu);
3071 }
3072
kvm_update_masterclock(struct kvm * kvm)3073 static void kvm_update_masterclock(struct kvm *kvm)
3074 {
3075 kvm_hv_request_tsc_page_update(kvm);
3076 kvm_start_pvclock_update(kvm);
3077 pvclock_update_vm_gtod_copy(kvm);
3078 kvm_end_pvclock_update(kvm);
3079 }
3080
3081 /*
3082 * Use the kernel's tsc_khz directly if the TSC is constant, otherwise use KVM's
3083 * per-CPU value (which may be zero if a CPU is going offline). Note, tsc_khz
3084 * can change during boot even if the TSC is constant, as it's possible for KVM
3085 * to be loaded before TSC calibration completes. Ideally, KVM would get a
3086 * notification when calibration completes, but practically speaking calibration
3087 * will complete before userspace is alive enough to create VMs.
3088 */
get_cpu_tsc_khz(void)3089 static unsigned long get_cpu_tsc_khz(void)
3090 {
3091 if (static_cpu_has(X86_FEATURE_CONSTANT_TSC))
3092 return tsc_khz;
3093 else
3094 return __this_cpu_read(cpu_tsc_khz);
3095 }
3096
3097 /* Called within read_seqcount_begin/retry for kvm->pvclock_sc. */
__get_kvmclock(struct kvm * kvm,struct kvm_clock_data * data)3098 static void __get_kvmclock(struct kvm *kvm, struct kvm_clock_data *data)
3099 {
3100 struct kvm_arch *ka = &kvm->arch;
3101 struct pvclock_vcpu_time_info hv_clock;
3102
3103 /* both __this_cpu_read() and rdtsc() should be on the same cpu */
3104 get_cpu();
3105
3106 data->flags = 0;
3107 if (ka->use_master_clock &&
3108 (static_cpu_has(X86_FEATURE_CONSTANT_TSC) || __this_cpu_read(cpu_tsc_khz))) {
3109 #ifdef CONFIG_X86_64
3110 struct timespec64 ts;
3111
3112 if (kvm_get_walltime_and_clockread(&ts, &data->host_tsc)) {
3113 data->realtime = ts.tv_nsec + NSEC_PER_SEC * ts.tv_sec;
3114 data->flags |= KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC;
3115 } else
3116 #endif
3117 data->host_tsc = rdtsc();
3118
3119 data->flags |= KVM_CLOCK_TSC_STABLE;
3120 hv_clock.tsc_timestamp = ka->master_cycle_now;
3121 hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset;
3122 kvm_get_time_scale(NSEC_PER_SEC, get_cpu_tsc_khz() * 1000LL,
3123 &hv_clock.tsc_shift,
3124 &hv_clock.tsc_to_system_mul);
3125 data->clock = __pvclock_read_cycles(&hv_clock, data->host_tsc);
3126 } else {
3127 data->clock = get_kvmclock_base_ns() + ka->kvmclock_offset;
3128 }
3129
3130 put_cpu();
3131 }
3132
get_kvmclock(struct kvm * kvm,struct kvm_clock_data * data)3133 static void get_kvmclock(struct kvm *kvm, struct kvm_clock_data *data)
3134 {
3135 struct kvm_arch *ka = &kvm->arch;
3136 unsigned seq;
3137
3138 do {
3139 seq = read_seqcount_begin(&ka->pvclock_sc);
3140 __get_kvmclock(kvm, data);
3141 } while (read_seqcount_retry(&ka->pvclock_sc, seq));
3142 }
3143
get_kvmclock_ns(struct kvm * kvm)3144 u64 get_kvmclock_ns(struct kvm *kvm)
3145 {
3146 struct kvm_clock_data data;
3147
3148 get_kvmclock(kvm, &data);
3149 return data.clock;
3150 }
3151
kvm_setup_guest_pvclock(struct pvclock_vcpu_time_info * ref_hv_clock,struct kvm_vcpu * vcpu,struct gfn_to_pfn_cache * gpc,unsigned int offset)3152 static void kvm_setup_guest_pvclock(struct pvclock_vcpu_time_info *ref_hv_clock,
3153 struct kvm_vcpu *vcpu,
3154 struct gfn_to_pfn_cache *gpc,
3155 unsigned int offset)
3156 {
3157 struct pvclock_vcpu_time_info *guest_hv_clock;
3158 struct pvclock_vcpu_time_info hv_clock;
3159 unsigned long flags;
3160
3161 memcpy(&hv_clock, ref_hv_clock, sizeof(hv_clock));
3162
3163 read_lock_irqsave(&gpc->lock, flags);
3164 while (!kvm_gpc_check(gpc, offset + sizeof(*guest_hv_clock))) {
3165 read_unlock_irqrestore(&gpc->lock, flags);
3166
3167 if (kvm_gpc_refresh(gpc, offset + sizeof(*guest_hv_clock)))
3168 return;
3169
3170 read_lock_irqsave(&gpc->lock, flags);
3171 }
3172
3173 guest_hv_clock = (void *)(gpc->khva + offset);
3174
3175 /*
3176 * This VCPU is paused, but it's legal for a guest to read another
3177 * VCPU's kvmclock, so we really have to follow the specification where
3178 * it says that version is odd if data is being modified, and even after
3179 * it is consistent.
3180 */
3181
3182 guest_hv_clock->version = hv_clock.version = (guest_hv_clock->version + 1) | 1;
3183 smp_wmb();
3184
3185 /* retain PVCLOCK_GUEST_STOPPED if set in guest copy */
3186 hv_clock.flags |= (guest_hv_clock->flags & PVCLOCK_GUEST_STOPPED);
3187
3188 memcpy(guest_hv_clock, &hv_clock, sizeof(*guest_hv_clock));
3189
3190 smp_wmb();
3191
3192 guest_hv_clock->version = ++hv_clock.version;
3193
3194 kvm_gpc_mark_dirty_in_slot(gpc);
3195 read_unlock_irqrestore(&gpc->lock, flags);
3196
3197 trace_kvm_pvclock_update(vcpu->vcpu_id, &hv_clock);
3198 }
3199
kvm_guest_time_update(struct kvm_vcpu * v)3200 int kvm_guest_time_update(struct kvm_vcpu *v)
3201 {
3202 struct pvclock_vcpu_time_info hv_clock = {};
3203 unsigned long flags, tgt_tsc_khz;
3204 unsigned seq;
3205 struct kvm_vcpu_arch *vcpu = &v->arch;
3206 struct kvm_arch *ka = &v->kvm->arch;
3207 s64 kernel_ns;
3208 u64 tsc_timestamp, host_tsc;
3209 bool use_master_clock;
3210
3211 kernel_ns = 0;
3212 host_tsc = 0;
3213
3214 /*
3215 * If the host uses TSC clock, then passthrough TSC as stable
3216 * to the guest.
3217 */
3218 do {
3219 seq = read_seqcount_begin(&ka->pvclock_sc);
3220 use_master_clock = ka->use_master_clock;
3221 if (use_master_clock) {
3222 host_tsc = ka->master_cycle_now;
3223 kernel_ns = ka->master_kernel_ns;
3224 }
3225 } while (read_seqcount_retry(&ka->pvclock_sc, seq));
3226
3227 /* Keep irq disabled to prevent changes to the clock */
3228 local_irq_save(flags);
3229 tgt_tsc_khz = get_cpu_tsc_khz();
3230 if (unlikely(tgt_tsc_khz == 0)) {
3231 local_irq_restore(flags);
3232 kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
3233 return 1;
3234 }
3235 if (!use_master_clock) {
3236 host_tsc = rdtsc();
3237 kernel_ns = get_kvmclock_base_ns();
3238 }
3239
3240 tsc_timestamp = kvm_read_l1_tsc(v, host_tsc);
3241
3242 /*
3243 * We may have to catch up the TSC to match elapsed wall clock
3244 * time for two reasons, even if kvmclock is used.
3245 * 1) CPU could have been running below the maximum TSC rate
3246 * 2) Broken TSC compensation resets the base at each VCPU
3247 * entry to avoid unknown leaps of TSC even when running
3248 * again on the same CPU. This may cause apparent elapsed
3249 * time to disappear, and the guest to stand still or run
3250 * very slowly.
3251 */
3252 if (vcpu->tsc_catchup) {
3253 u64 tsc = compute_guest_tsc(v, kernel_ns);
3254 if (tsc > tsc_timestamp) {
3255 adjust_tsc_offset_guest(v, tsc - tsc_timestamp);
3256 tsc_timestamp = tsc;
3257 }
3258 }
3259
3260 local_irq_restore(flags);
3261
3262 /* With all the info we got, fill in the values */
3263
3264 if (kvm_caps.has_tsc_control) {
3265 tgt_tsc_khz = kvm_scale_tsc(tgt_tsc_khz,
3266 v->arch.l1_tsc_scaling_ratio);
3267 tgt_tsc_khz = tgt_tsc_khz ? : 1;
3268 }
3269
3270 if (unlikely(vcpu->hw_tsc_khz != tgt_tsc_khz)) {
3271 kvm_get_time_scale(NSEC_PER_SEC, tgt_tsc_khz * 1000LL,
3272 &vcpu->pvclock_tsc_shift,
3273 &vcpu->pvclock_tsc_mul);
3274 vcpu->hw_tsc_khz = tgt_tsc_khz;
3275 }
3276
3277 hv_clock.tsc_shift = vcpu->pvclock_tsc_shift;
3278 hv_clock.tsc_to_system_mul = vcpu->pvclock_tsc_mul;
3279 hv_clock.tsc_timestamp = tsc_timestamp;
3280 hv_clock.system_time = kernel_ns + v->kvm->arch.kvmclock_offset;
3281 vcpu->last_guest_tsc = tsc_timestamp;
3282
3283 /* If the host uses TSC clocksource, then it is stable */
3284 hv_clock.flags = 0;
3285 if (use_master_clock)
3286 hv_clock.flags |= PVCLOCK_TSC_STABLE_BIT;
3287
3288 if (vcpu->pv_time.active) {
3289 /*
3290 * GUEST_STOPPED is only supported by kvmclock, and KVM's
3291 * historic behavior is to only process the request if kvmclock
3292 * is active/enabled.
3293 */
3294 if (vcpu->pvclock_set_guest_stopped_request) {
3295 hv_clock.flags |= PVCLOCK_GUEST_STOPPED;
3296 vcpu->pvclock_set_guest_stopped_request = false;
3297 }
3298 kvm_setup_guest_pvclock(&hv_clock, v, &vcpu->pv_time, 0);
3299
3300 hv_clock.flags &= ~PVCLOCK_GUEST_STOPPED;
3301 }
3302
3303 kvm_hv_setup_tsc_page(v->kvm, &hv_clock);
3304
3305 #ifdef CONFIG_KVM_XEN
3306 /*
3307 * For Xen guests we may need to override PVCLOCK_TSC_STABLE_BIT as unless
3308 * explicitly told to use TSC as its clocksource Xen will not set this bit.
3309 * This default behaviour led to bugs in some guest kernels which cause
3310 * problems if they observe PVCLOCK_TSC_STABLE_BIT in the pvclock flags.
3311 *
3312 * Note! Clear TSC_STABLE only for Xen clocks, i.e. the order matters!
3313 */
3314 if (ka->xen.hvm_config.flags & KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE)
3315 hv_clock.flags &= ~PVCLOCK_TSC_STABLE_BIT;
3316
3317 if (vcpu->xen.vcpu_info_cache.active)
3318 kvm_setup_guest_pvclock(&hv_clock, v, &vcpu->xen.vcpu_info_cache,
3319 offsetof(struct compat_vcpu_info, time));
3320 if (vcpu->xen.vcpu_time_info_cache.active)
3321 kvm_setup_guest_pvclock(&hv_clock, v, &vcpu->xen.vcpu_time_info_cache, 0);
3322 #endif
3323 return 0;
3324 }
3325
3326 /*
3327 * The pvclock_wall_clock ABI tells the guest the wall clock time at
3328 * which it started (i.e. its epoch, when its kvmclock was zero).
3329 *
3330 * In fact those clocks are subtly different; wall clock frequency is
3331 * adjusted by NTP and has leap seconds, while the kvmclock is a
3332 * simple function of the TSC without any such adjustment.
3333 *
3334 * Perhaps the ABI should have exposed CLOCK_TAI and a ratio between
3335 * that and kvmclock, but even that would be subject to change over
3336 * time.
3337 *
3338 * Attempt to calculate the epoch at a given moment using the *same*
3339 * TSC reading via kvm_get_walltime_and_clockread() to obtain both
3340 * wallclock and kvmclock times, and subtracting one from the other.
3341 *
3342 * Fall back to using their values at slightly different moments by
3343 * calling ktime_get_real_ns() and get_kvmclock_ns() separately.
3344 */
kvm_get_wall_clock_epoch(struct kvm * kvm)3345 uint64_t kvm_get_wall_clock_epoch(struct kvm *kvm)
3346 {
3347 #ifdef CONFIG_X86_64
3348 struct pvclock_vcpu_time_info hv_clock;
3349 struct kvm_arch *ka = &kvm->arch;
3350 unsigned long seq, local_tsc_khz;
3351 struct timespec64 ts;
3352 uint64_t host_tsc;
3353
3354 do {
3355 seq = read_seqcount_begin(&ka->pvclock_sc);
3356
3357 local_tsc_khz = 0;
3358 if (!ka->use_master_clock)
3359 break;
3360
3361 /*
3362 * The TSC read and the call to get_cpu_tsc_khz() must happen
3363 * on the same CPU.
3364 */
3365 get_cpu();
3366
3367 local_tsc_khz = get_cpu_tsc_khz();
3368
3369 if (local_tsc_khz &&
3370 !kvm_get_walltime_and_clockread(&ts, &host_tsc))
3371 local_tsc_khz = 0; /* Fall back to old method */
3372
3373 put_cpu();
3374
3375 /*
3376 * These values must be snapshotted within the seqcount loop.
3377 * After that, it's just mathematics which can happen on any
3378 * CPU at any time.
3379 */
3380 hv_clock.tsc_timestamp = ka->master_cycle_now;
3381 hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset;
3382
3383 } while (read_seqcount_retry(&ka->pvclock_sc, seq));
3384
3385 /*
3386 * If the conditions were right, and obtaining the wallclock+TSC was
3387 * successful, calculate the KVM clock at the corresponding time and
3388 * subtract one from the other to get the guest's epoch in nanoseconds
3389 * since 1970-01-01.
3390 */
3391 if (local_tsc_khz) {
3392 kvm_get_time_scale(NSEC_PER_SEC, local_tsc_khz * NSEC_PER_USEC,
3393 &hv_clock.tsc_shift,
3394 &hv_clock.tsc_to_system_mul);
3395 return ts.tv_nsec + NSEC_PER_SEC * ts.tv_sec -
3396 __pvclock_read_cycles(&hv_clock, host_tsc);
3397 }
3398 #endif
3399 return ktime_get_real_ns() - get_kvmclock_ns(kvm);
3400 }
3401
3402 /*
3403 * kvmclock updates which are isolated to a given vcpu, such as
3404 * vcpu->cpu migration, should not allow system_timestamp from
3405 * the rest of the vcpus to remain static. Otherwise ntp frequency
3406 * correction applies to one vcpu's system_timestamp but not
3407 * the others.
3408 *
3409 * So in those cases, request a kvmclock update for all vcpus.
3410 * We need to rate-limit these requests though, as they can
3411 * considerably slow guests that have a large number of vcpus.
3412 * The time for a remote vcpu to update its kvmclock is bound
3413 * by the delay we use to rate-limit the updates.
3414 */
3415
3416 #define KVMCLOCK_UPDATE_DELAY msecs_to_jiffies(100)
3417
kvmclock_update_fn(struct work_struct * work)3418 static void kvmclock_update_fn(struct work_struct *work)
3419 {
3420 unsigned long i;
3421 struct delayed_work *dwork = to_delayed_work(work);
3422 struct kvm_arch *ka = container_of(dwork, struct kvm_arch,
3423 kvmclock_update_work);
3424 struct kvm *kvm = container_of(ka, struct kvm, arch);
3425 struct kvm_vcpu *vcpu;
3426
3427 kvm_for_each_vcpu(i, vcpu, kvm) {
3428 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
3429 kvm_vcpu_kick(vcpu);
3430 }
3431 }
3432
kvm_gen_kvmclock_update(struct kvm_vcpu * v)3433 static void kvm_gen_kvmclock_update(struct kvm_vcpu *v)
3434 {
3435 struct kvm *kvm = v->kvm;
3436
3437 kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
3438 schedule_delayed_work(&kvm->arch.kvmclock_update_work,
3439 KVMCLOCK_UPDATE_DELAY);
3440 }
3441
3442 #define KVMCLOCK_SYNC_PERIOD (300 * HZ)
3443
kvmclock_sync_fn(struct work_struct * work)3444 static void kvmclock_sync_fn(struct work_struct *work)
3445 {
3446 struct delayed_work *dwork = to_delayed_work(work);
3447 struct kvm_arch *ka = container_of(dwork, struct kvm_arch,
3448 kvmclock_sync_work);
3449 struct kvm *kvm = container_of(ka, struct kvm, arch);
3450
3451 schedule_delayed_work(&kvm->arch.kvmclock_update_work, 0);
3452 schedule_delayed_work(&kvm->arch.kvmclock_sync_work,
3453 KVMCLOCK_SYNC_PERIOD);
3454 }
3455
3456 /* These helpers are safe iff @msr is known to be an MCx bank MSR. */
is_mci_control_msr(u32 msr)3457 static bool is_mci_control_msr(u32 msr)
3458 {
3459 return (msr & 3) == 0;
3460 }
is_mci_status_msr(u32 msr)3461 static bool is_mci_status_msr(u32 msr)
3462 {
3463 return (msr & 3) == 1;
3464 }
3465
3466 /*
3467 * On AMD, HWCR[McStatusWrEn] controls whether setting MCi_STATUS results in #GP.
3468 */
can_set_mci_status(struct kvm_vcpu * vcpu)3469 static bool can_set_mci_status(struct kvm_vcpu *vcpu)
3470 {
3471 /* McStatusWrEn enabled? */
3472 if (guest_cpuid_is_amd_compatible(vcpu))
3473 return !!(vcpu->arch.msr_hwcr & BIT_ULL(18));
3474
3475 return false;
3476 }
3477
set_msr_mce(struct kvm_vcpu * vcpu,struct msr_data * msr_info)3478 static int set_msr_mce(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
3479 {
3480 u64 mcg_cap = vcpu->arch.mcg_cap;
3481 unsigned bank_num = mcg_cap & 0xff;
3482 u32 msr = msr_info->index;
3483 u64 data = msr_info->data;
3484 u32 offset, last_msr;
3485
3486 switch (msr) {
3487 case MSR_IA32_MCG_STATUS:
3488 vcpu->arch.mcg_status = data;
3489 break;
3490 case MSR_IA32_MCG_CTL:
3491 if (!(mcg_cap & MCG_CTL_P) &&
3492 (data || !msr_info->host_initiated))
3493 return 1;
3494 if (data != 0 && data != ~(u64)0)
3495 return 1;
3496 vcpu->arch.mcg_ctl = data;
3497 break;
3498 case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
3499 last_msr = MSR_IA32_MCx_CTL2(bank_num) - 1;
3500 if (msr > last_msr)
3501 return 1;
3502
3503 if (!(mcg_cap & MCG_CMCI_P) && (data || !msr_info->host_initiated))
3504 return 1;
3505 /* An attempt to write a 1 to a reserved bit raises #GP */
3506 if (data & ~(MCI_CTL2_CMCI_EN | MCI_CTL2_CMCI_THRESHOLD_MASK))
3507 return 1;
3508 offset = array_index_nospec(msr - MSR_IA32_MC0_CTL2,
3509 last_msr + 1 - MSR_IA32_MC0_CTL2);
3510 vcpu->arch.mci_ctl2_banks[offset] = data;
3511 break;
3512 case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
3513 last_msr = MSR_IA32_MCx_CTL(bank_num) - 1;
3514 if (msr > last_msr)
3515 return 1;
3516
3517 /*
3518 * Only 0 or all 1s can be written to IA32_MCi_CTL, all other
3519 * values are architecturally undefined. But, some Linux
3520 * kernels clear bit 10 in bank 4 to workaround a BIOS/GART TLB
3521 * issue on AMD K8s, allow bit 10 to be clear when setting all
3522 * other bits in order to avoid an uncaught #GP in the guest.
3523 *
3524 * UNIXWARE clears bit 0 of MC1_CTL to ignore correctable,
3525 * single-bit ECC data errors.
3526 */
3527 if (is_mci_control_msr(msr) &&
3528 data != 0 && (data | (1 << 10) | 1) != ~(u64)0)
3529 return 1;
3530
3531 /*
3532 * All CPUs allow writing 0 to MCi_STATUS MSRs to clear the MSR.
3533 * AMD-based CPUs allow non-zero values, but if and only if
3534 * HWCR[McStatusWrEn] is set.
3535 */
3536 if (!msr_info->host_initiated && is_mci_status_msr(msr) &&
3537 data != 0 && !can_set_mci_status(vcpu))
3538 return 1;
3539
3540 offset = array_index_nospec(msr - MSR_IA32_MC0_CTL,
3541 last_msr + 1 - MSR_IA32_MC0_CTL);
3542 vcpu->arch.mce_banks[offset] = data;
3543 break;
3544 default:
3545 return 1;
3546 }
3547 return 0;
3548 }
3549
kvm_pv_async_pf_enabled(struct kvm_vcpu * vcpu)3550 static inline bool kvm_pv_async_pf_enabled(struct kvm_vcpu *vcpu)
3551 {
3552 u64 mask = KVM_ASYNC_PF_ENABLED | KVM_ASYNC_PF_DELIVERY_AS_INT;
3553
3554 return (vcpu->arch.apf.msr_en_val & mask) == mask;
3555 }
3556
kvm_pv_enable_async_pf(struct kvm_vcpu * vcpu,u64 data)3557 static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data)
3558 {
3559 gpa_t gpa = data & ~0x3f;
3560
3561 /* Bits 4:5 are reserved, Should be zero */
3562 if (data & 0x30)
3563 return 1;
3564
3565 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_VMEXIT) &&
3566 (data & KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT))
3567 return 1;
3568
3569 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT) &&
3570 (data & KVM_ASYNC_PF_DELIVERY_AS_INT))
3571 return 1;
3572
3573 if (!lapic_in_kernel(vcpu))
3574 return data ? 1 : 0;
3575
3576 vcpu->arch.apf.msr_en_val = data;
3577
3578 if (!kvm_pv_async_pf_enabled(vcpu)) {
3579 kvm_clear_async_pf_completion_queue(vcpu);
3580 kvm_async_pf_hash_reset(vcpu);
3581 return 0;
3582 }
3583
3584 if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.apf.data, gpa,
3585 sizeof(u64)))
3586 return 1;
3587
3588 vcpu->arch.apf.send_always = (data & KVM_ASYNC_PF_SEND_ALWAYS);
3589 vcpu->arch.apf.delivery_as_pf_vmexit = data & KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT;
3590
3591 kvm_async_pf_wakeup_all(vcpu);
3592
3593 return 0;
3594 }
3595
kvm_pv_enable_async_pf_int(struct kvm_vcpu * vcpu,u64 data)3596 static int kvm_pv_enable_async_pf_int(struct kvm_vcpu *vcpu, u64 data)
3597 {
3598 /* Bits 8-63 are reserved */
3599 if (data >> 8)
3600 return 1;
3601
3602 if (!lapic_in_kernel(vcpu))
3603 return 1;
3604
3605 vcpu->arch.apf.msr_int_val = data;
3606
3607 vcpu->arch.apf.vec = data & KVM_ASYNC_PF_VEC_MASK;
3608
3609 return 0;
3610 }
3611
kvmclock_reset(struct kvm_vcpu * vcpu)3612 static void kvmclock_reset(struct kvm_vcpu *vcpu)
3613 {
3614 kvm_gpc_deactivate(&vcpu->arch.pv_time);
3615 vcpu->arch.time = 0;
3616 }
3617
kvm_vcpu_flush_tlb_all(struct kvm_vcpu * vcpu)3618 static void kvm_vcpu_flush_tlb_all(struct kvm_vcpu *vcpu)
3619 {
3620 ++vcpu->stat.tlb_flush;
3621 kvm_x86_call(flush_tlb_all)(vcpu);
3622
3623 /* Flushing all ASIDs flushes the current ASID... */
3624 kvm_clear_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
3625 }
3626
kvm_vcpu_flush_tlb_guest(struct kvm_vcpu * vcpu)3627 static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu)
3628 {
3629 ++vcpu->stat.tlb_flush;
3630
3631 if (!tdp_enabled) {
3632 /*
3633 * A TLB flush on behalf of the guest is equivalent to
3634 * INVPCID(all), toggling CR4.PGE, etc., which requires
3635 * a forced sync of the shadow page tables. Ensure all the
3636 * roots are synced and the guest TLB in hardware is clean.
3637 */
3638 kvm_mmu_sync_roots(vcpu);
3639 kvm_mmu_sync_prev_roots(vcpu);
3640 }
3641
3642 kvm_x86_call(flush_tlb_guest)(vcpu);
3643
3644 /*
3645 * Flushing all "guest" TLB is always a superset of Hyper-V's fine
3646 * grained flushing.
3647 */
3648 kvm_hv_vcpu_purge_flush_tlb(vcpu);
3649 }
3650
3651
kvm_vcpu_flush_tlb_current(struct kvm_vcpu * vcpu)3652 static inline void kvm_vcpu_flush_tlb_current(struct kvm_vcpu *vcpu)
3653 {
3654 ++vcpu->stat.tlb_flush;
3655 kvm_x86_call(flush_tlb_current)(vcpu);
3656 }
3657
3658 /*
3659 * Service "local" TLB flush requests, which are specific to the current MMU
3660 * context. In addition to the generic event handling in vcpu_enter_guest(),
3661 * TLB flushes that are targeted at an MMU context also need to be serviced
3662 * prior before nested VM-Enter/VM-Exit.
3663 */
kvm_service_local_tlb_flush_requests(struct kvm_vcpu * vcpu)3664 void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu)
3665 {
3666 if (kvm_check_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu))
3667 kvm_vcpu_flush_tlb_current(vcpu);
3668
3669 if (kvm_check_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu))
3670 kvm_vcpu_flush_tlb_guest(vcpu);
3671 }
3672 EXPORT_SYMBOL_GPL(kvm_service_local_tlb_flush_requests);
3673
record_steal_time(struct kvm_vcpu * vcpu)3674 static void record_steal_time(struct kvm_vcpu *vcpu)
3675 {
3676 struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache;
3677 struct kvm_steal_time __user *st;
3678 struct kvm_memslots *slots;
3679 gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS;
3680 u64 steal;
3681 u32 version;
3682
3683 if (kvm_xen_msr_enabled(vcpu->kvm)) {
3684 kvm_xen_runstate_set_running(vcpu);
3685 return;
3686 }
3687
3688 if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
3689 return;
3690
3691 if (WARN_ON_ONCE(current->mm != vcpu->kvm->mm))
3692 return;
3693
3694 slots = kvm_memslots(vcpu->kvm);
3695
3696 if (unlikely(slots->generation != ghc->generation ||
3697 gpa != ghc->gpa ||
3698 kvm_is_error_hva(ghc->hva) || !ghc->memslot)) {
3699 /* We rely on the fact that it fits in a single page. */
3700 BUILD_BUG_ON((sizeof(*st) - 1) & KVM_STEAL_VALID_BITS);
3701
3702 if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, sizeof(*st)) ||
3703 kvm_is_error_hva(ghc->hva) || !ghc->memslot)
3704 return;
3705 }
3706
3707 st = (struct kvm_steal_time __user *)ghc->hva;
3708 /*
3709 * Doing a TLB flush here, on the guest's behalf, can avoid
3710 * expensive IPIs.
3711 */
3712 if (guest_pv_has(vcpu, KVM_FEATURE_PV_TLB_FLUSH)) {
3713 u8 st_preempted = 0;
3714 int err = -EFAULT;
3715
3716 if (!user_access_begin(st, sizeof(*st)))
3717 return;
3718
3719 asm volatile("1: xchgb %0, %2\n"
3720 "xor %1, %1\n"
3721 "2:\n"
3722 _ASM_EXTABLE_UA(1b, 2b)
3723 : "+q" (st_preempted),
3724 "+&r" (err),
3725 "+m" (st->preempted));
3726 if (err)
3727 goto out;
3728
3729 user_access_end();
3730
3731 vcpu->arch.st.preempted = 0;
3732
3733 trace_kvm_pv_tlb_flush(vcpu->vcpu_id,
3734 st_preempted & KVM_VCPU_FLUSH_TLB);
3735 if (st_preempted & KVM_VCPU_FLUSH_TLB)
3736 kvm_vcpu_flush_tlb_guest(vcpu);
3737
3738 if (!user_access_begin(st, sizeof(*st)))
3739 goto dirty;
3740 } else {
3741 if (!user_access_begin(st, sizeof(*st)))
3742 return;
3743
3744 unsafe_put_user(0, &st->preempted, out);
3745 vcpu->arch.st.preempted = 0;
3746 }
3747
3748 unsafe_get_user(version, &st->version, out);
3749 if (version & 1)
3750 version += 1; /* first time write, random junk */
3751
3752 version += 1;
3753 unsafe_put_user(version, &st->version, out);
3754
3755 smp_wmb();
3756
3757 unsafe_get_user(steal, &st->steal, out);
3758 steal += current->sched_info.run_delay -
3759 vcpu->arch.st.last_steal;
3760 vcpu->arch.st.last_steal = current->sched_info.run_delay;
3761 unsafe_put_user(steal, &st->steal, out);
3762
3763 version += 1;
3764 unsafe_put_user(version, &st->version, out);
3765
3766 out:
3767 user_access_end();
3768 dirty:
3769 mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
3770 }
3771
kvm_set_msr_common(struct kvm_vcpu * vcpu,struct msr_data * msr_info)3772 int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
3773 {
3774 u32 msr = msr_info->index;
3775 u64 data = msr_info->data;
3776
3777 /*
3778 * Do not allow host-initiated writes to trigger the Xen hypercall
3779 * page setup; it could incur locking paths which are not expected
3780 * if userspace sets the MSR in an unusual location.
3781 */
3782 if (kvm_xen_is_hypercall_page_msr(vcpu->kvm, msr) &&
3783 !msr_info->host_initiated)
3784 return kvm_xen_write_hypercall_page(vcpu, data);
3785
3786 switch (msr) {
3787 case MSR_AMD64_NB_CFG:
3788 case MSR_IA32_UCODE_WRITE:
3789 case MSR_VM_HSAVE_PA:
3790 case MSR_AMD64_PATCH_LOADER:
3791 case MSR_AMD64_BU_CFG2:
3792 case MSR_AMD64_DC_CFG:
3793 case MSR_AMD64_TW_CFG:
3794 case MSR_F15H_EX_CFG:
3795 break;
3796
3797 case MSR_IA32_UCODE_REV:
3798 if (msr_info->host_initiated)
3799 vcpu->arch.microcode_version = data;
3800 break;
3801 case MSR_IA32_ARCH_CAPABILITIES:
3802 if (!msr_info->host_initiated ||
3803 !guest_cpu_cap_has(vcpu, X86_FEATURE_ARCH_CAPABILITIES))
3804 return KVM_MSR_RET_UNSUPPORTED;
3805 vcpu->arch.arch_capabilities = data;
3806 break;
3807 case MSR_IA32_PERF_CAPABILITIES:
3808 if (!msr_info->host_initiated ||
3809 !guest_cpu_cap_has(vcpu, X86_FEATURE_PDCM))
3810 return KVM_MSR_RET_UNSUPPORTED;
3811
3812 if (data & ~kvm_caps.supported_perf_cap)
3813 return 1;
3814
3815 /*
3816 * Note, this is not just a performance optimization! KVM
3817 * disallows changing feature MSRs after the vCPU has run; PMU
3818 * refresh will bug the VM if called after the vCPU has run.
3819 */
3820 if (vcpu->arch.perf_capabilities == data)
3821 break;
3822
3823 vcpu->arch.perf_capabilities = data;
3824 kvm_pmu_refresh(vcpu);
3825 break;
3826 case MSR_IA32_PRED_CMD: {
3827 u64 reserved_bits = ~(PRED_CMD_IBPB | PRED_CMD_SBPB);
3828
3829 if (!msr_info->host_initiated) {
3830 if ((!guest_has_pred_cmd_msr(vcpu)))
3831 return 1;
3832
3833 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SPEC_CTRL) &&
3834 !guest_cpu_cap_has(vcpu, X86_FEATURE_AMD_IBPB))
3835 reserved_bits |= PRED_CMD_IBPB;
3836
3837 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SBPB))
3838 reserved_bits |= PRED_CMD_SBPB;
3839 }
3840
3841 if (!boot_cpu_has(X86_FEATURE_IBPB))
3842 reserved_bits |= PRED_CMD_IBPB;
3843
3844 if (!boot_cpu_has(X86_FEATURE_SBPB))
3845 reserved_bits |= PRED_CMD_SBPB;
3846
3847 if (data & reserved_bits)
3848 return 1;
3849
3850 if (!data)
3851 break;
3852
3853 wrmsrq(MSR_IA32_PRED_CMD, data);
3854 break;
3855 }
3856 case MSR_IA32_FLUSH_CMD:
3857 if (!msr_info->host_initiated &&
3858 !guest_cpu_cap_has(vcpu, X86_FEATURE_FLUSH_L1D))
3859 return 1;
3860
3861 if (!boot_cpu_has(X86_FEATURE_FLUSH_L1D) || (data & ~L1D_FLUSH))
3862 return 1;
3863 if (!data)
3864 break;
3865
3866 wrmsrq(MSR_IA32_FLUSH_CMD, L1D_FLUSH);
3867 break;
3868 case MSR_EFER:
3869 return set_efer(vcpu, msr_info);
3870 case MSR_K7_HWCR:
3871 data &= ~(u64)0x40; /* ignore flush filter disable */
3872 data &= ~(u64)0x100; /* ignore ignne emulation enable */
3873 data &= ~(u64)0x8; /* ignore TLB cache disable */
3874
3875 /*
3876 * Allow McStatusWrEn and TscFreqSel. (Linux guests from v3.2
3877 * through at least v6.6 whine if TscFreqSel is clear,
3878 * depending on F/M/S.
3879 */
3880 if (data & ~(BIT_ULL(18) | BIT_ULL(24))) {
3881 kvm_pr_unimpl_wrmsr(vcpu, msr, data);
3882 return 1;
3883 }
3884 vcpu->arch.msr_hwcr = data;
3885 break;
3886 case MSR_FAM10H_MMIO_CONF_BASE:
3887 if (data != 0) {
3888 kvm_pr_unimpl_wrmsr(vcpu, msr, data);
3889 return 1;
3890 }
3891 break;
3892 case MSR_IA32_CR_PAT:
3893 if (!kvm_pat_valid(data))
3894 return 1;
3895
3896 vcpu->arch.pat = data;
3897 break;
3898 case MTRRphysBase_MSR(0) ... MSR_MTRRfix4K_F8000:
3899 case MSR_MTRRdefType:
3900 return kvm_mtrr_set_msr(vcpu, msr, data);
3901 case MSR_IA32_APICBASE:
3902 return kvm_apic_set_base(vcpu, data, msr_info->host_initiated);
3903 case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
3904 return kvm_x2apic_msr_write(vcpu, msr, data);
3905 case MSR_IA32_TSC_DEADLINE:
3906 kvm_set_lapic_tscdeadline_msr(vcpu, data);
3907 break;
3908 case MSR_IA32_TSC_ADJUST:
3909 if (guest_cpu_cap_has(vcpu, X86_FEATURE_TSC_ADJUST)) {
3910 if (!msr_info->host_initiated) {
3911 s64 adj = data - vcpu->arch.ia32_tsc_adjust_msr;
3912 adjust_tsc_offset_guest(vcpu, adj);
3913 /* Before back to guest, tsc_timestamp must be adjusted
3914 * as well, otherwise guest's percpu pvclock time could jump.
3915 */
3916 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
3917 }
3918 vcpu->arch.ia32_tsc_adjust_msr = data;
3919 }
3920 break;
3921 case MSR_IA32_MISC_ENABLE: {
3922 u64 old_val = vcpu->arch.ia32_misc_enable_msr;
3923
3924 if (!msr_info->host_initiated) {
3925 /* RO bits */
3926 if ((old_val ^ data) & MSR_IA32_MISC_ENABLE_PMU_RO_MASK)
3927 return 1;
3928
3929 /* R bits, i.e. writes are ignored, but don't fault. */
3930 data = data & ~MSR_IA32_MISC_ENABLE_EMON;
3931 data |= old_val & MSR_IA32_MISC_ENABLE_EMON;
3932 }
3933
3934 if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT) &&
3935 ((old_val ^ data) & MSR_IA32_MISC_ENABLE_MWAIT)) {
3936 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_XMM3))
3937 return 1;
3938 vcpu->arch.ia32_misc_enable_msr = data;
3939 vcpu->arch.cpuid_dynamic_bits_dirty = true;
3940 } else {
3941 vcpu->arch.ia32_misc_enable_msr = data;
3942 }
3943 break;
3944 }
3945 case MSR_IA32_SMBASE:
3946 if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated)
3947 return 1;
3948 vcpu->arch.smbase = data;
3949 break;
3950 case MSR_IA32_POWER_CTL:
3951 vcpu->arch.msr_ia32_power_ctl = data;
3952 break;
3953 case MSR_IA32_TSC:
3954 if (msr_info->host_initiated) {
3955 kvm_synchronize_tsc(vcpu, &data);
3956 } else if (!vcpu->arch.guest_tsc_protected) {
3957 u64 adj = kvm_compute_l1_tsc_offset(vcpu, data) - vcpu->arch.l1_tsc_offset;
3958 adjust_tsc_offset_guest(vcpu, adj);
3959 vcpu->arch.ia32_tsc_adjust_msr += adj;
3960 }
3961 break;
3962 case MSR_IA32_XSS:
3963 if (!msr_info->host_initiated &&
3964 !guest_cpuid_has(vcpu, X86_FEATURE_XSAVES))
3965 return 1;
3966 /*
3967 * KVM supports exposing PT to the guest, but does not support
3968 * IA32_XSS[bit 8]. Guests have to use RDMSR/WRMSR rather than
3969 * XSAVES/XRSTORS to save/restore PT MSRs.
3970 */
3971 if (data & ~kvm_caps.supported_xss)
3972 return 1;
3973 vcpu->arch.ia32_xss = data;
3974 vcpu->arch.cpuid_dynamic_bits_dirty = true;
3975 break;
3976 case MSR_SMI_COUNT:
3977 if (!msr_info->host_initiated)
3978 return 1;
3979 vcpu->arch.smi_count = data;
3980 break;
3981 case MSR_KVM_WALL_CLOCK_NEW:
3982 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
3983 return 1;
3984
3985 vcpu->kvm->arch.wall_clock = data;
3986 kvm_write_wall_clock(vcpu->kvm, data, 0);
3987 break;
3988 case MSR_KVM_WALL_CLOCK:
3989 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
3990 return 1;
3991
3992 vcpu->kvm->arch.wall_clock = data;
3993 kvm_write_wall_clock(vcpu->kvm, data, 0);
3994 break;
3995 case MSR_KVM_SYSTEM_TIME_NEW:
3996 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
3997 return 1;
3998
3999 kvm_write_system_time(vcpu, data, false, msr_info->host_initiated);
4000 break;
4001 case MSR_KVM_SYSTEM_TIME:
4002 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
4003 return 1;
4004
4005 kvm_write_system_time(vcpu, data, true, msr_info->host_initiated);
4006 break;
4007 case MSR_KVM_ASYNC_PF_EN:
4008 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
4009 return 1;
4010
4011 if (kvm_pv_enable_async_pf(vcpu, data))
4012 return 1;
4013 break;
4014 case MSR_KVM_ASYNC_PF_INT:
4015 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4016 return 1;
4017
4018 if (kvm_pv_enable_async_pf_int(vcpu, data))
4019 return 1;
4020 break;
4021 case MSR_KVM_ASYNC_PF_ACK:
4022 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4023 return 1;
4024 if (data & 0x1) {
4025 vcpu->arch.apf.pageready_pending = false;
4026 kvm_check_async_pf_completion(vcpu);
4027 }
4028 break;
4029 case MSR_KVM_STEAL_TIME:
4030 if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME))
4031 return 1;
4032
4033 if (unlikely(!sched_info_on()))
4034 return 1;
4035
4036 if (data & KVM_STEAL_RESERVED_MASK)
4037 return 1;
4038
4039 vcpu->arch.st.msr_val = data;
4040
4041 if (!(data & KVM_MSR_ENABLED))
4042 break;
4043
4044 kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
4045
4046 break;
4047 case MSR_KVM_PV_EOI_EN:
4048 if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI))
4049 return 1;
4050
4051 if (kvm_lapic_set_pv_eoi(vcpu, data, sizeof(u8)))
4052 return 1;
4053 break;
4054
4055 case MSR_KVM_POLL_CONTROL:
4056 if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL))
4057 return 1;
4058
4059 /* only enable bit supported */
4060 if (data & (-1ULL << 1))
4061 return 1;
4062
4063 vcpu->arch.msr_kvm_poll_control = data;
4064 break;
4065
4066 case MSR_IA32_MCG_CTL:
4067 case MSR_IA32_MCG_STATUS:
4068 case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
4069 case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
4070 return set_msr_mce(vcpu, msr_info);
4071
4072 case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3:
4073 case MSR_P6_PERFCTR0 ... MSR_P6_PERFCTR1:
4074 case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3:
4075 case MSR_P6_EVNTSEL0 ... MSR_P6_EVNTSEL1:
4076 if (kvm_pmu_is_valid_msr(vcpu, msr))
4077 return kvm_pmu_set_msr(vcpu, msr_info);
4078
4079 if (data)
4080 kvm_pr_unimpl_wrmsr(vcpu, msr, data);
4081 break;
4082 case MSR_K7_CLK_CTL:
4083 /*
4084 * Ignore all writes to this no longer documented MSR.
4085 * Writes are only relevant for old K7 processors,
4086 * all pre-dating SVM, but a recommended workaround from
4087 * AMD for these chips. It is possible to specify the
4088 * affected processor models on the command line, hence
4089 * the need to ignore the workaround.
4090 */
4091 break;
4092 #ifdef CONFIG_KVM_HYPERV
4093 case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
4094 case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
4095 case HV_X64_MSR_SYNDBG_OPTIONS:
4096 case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
4097 case HV_X64_MSR_CRASH_CTL:
4098 case HV_X64_MSR_STIMER0_CONFIG ... HV_X64_MSR_STIMER3_COUNT:
4099 case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
4100 case HV_X64_MSR_TSC_EMULATION_CONTROL:
4101 case HV_X64_MSR_TSC_EMULATION_STATUS:
4102 case HV_X64_MSR_TSC_INVARIANT_CONTROL:
4103 return kvm_hv_set_msr_common(vcpu, msr, data,
4104 msr_info->host_initiated);
4105 #endif
4106 case MSR_IA32_BBL_CR_CTL3:
4107 /* Drop writes to this legacy MSR -- see rdmsr
4108 * counterpart for further detail.
4109 */
4110 kvm_pr_unimpl_wrmsr(vcpu, msr, data);
4111 break;
4112 case MSR_AMD64_OSVW_ID_LENGTH:
4113 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_OSVW))
4114 return 1;
4115 vcpu->arch.osvw.length = data;
4116 break;
4117 case MSR_AMD64_OSVW_STATUS:
4118 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_OSVW))
4119 return 1;
4120 vcpu->arch.osvw.status = data;
4121 break;
4122 case MSR_PLATFORM_INFO:
4123 if (!msr_info->host_initiated)
4124 return 1;
4125 vcpu->arch.msr_platform_info = data;
4126 break;
4127 case MSR_MISC_FEATURES_ENABLES:
4128 if (data & ~MSR_MISC_FEATURES_ENABLES_CPUID_FAULT ||
4129 (data & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT &&
4130 !supports_cpuid_fault(vcpu)))
4131 return 1;
4132 vcpu->arch.msr_misc_features_enables = data;
4133 break;
4134 #ifdef CONFIG_X86_64
4135 case MSR_IA32_XFD:
4136 if (!msr_info->host_initiated &&
4137 !guest_cpu_cap_has(vcpu, X86_FEATURE_XFD))
4138 return 1;
4139
4140 if (data & ~kvm_guest_supported_xfd(vcpu))
4141 return 1;
4142
4143 fpu_update_guest_xfd(&vcpu->arch.guest_fpu, data);
4144 break;
4145 case MSR_IA32_XFD_ERR:
4146 if (!msr_info->host_initiated &&
4147 !guest_cpu_cap_has(vcpu, X86_FEATURE_XFD))
4148 return 1;
4149
4150 if (data & ~kvm_guest_supported_xfd(vcpu))
4151 return 1;
4152
4153 vcpu->arch.guest_fpu.xfd_err = data;
4154 break;
4155 #endif
4156 default:
4157 if (kvm_pmu_is_valid_msr(vcpu, msr))
4158 return kvm_pmu_set_msr(vcpu, msr_info);
4159
4160 return KVM_MSR_RET_UNSUPPORTED;
4161 }
4162 return 0;
4163 }
4164 EXPORT_SYMBOL_GPL(kvm_set_msr_common);
4165
get_msr_mce(struct kvm_vcpu * vcpu,u32 msr,u64 * pdata,bool host)4166 static int get_msr_mce(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
4167 {
4168 u64 data;
4169 u64 mcg_cap = vcpu->arch.mcg_cap;
4170 unsigned bank_num = mcg_cap & 0xff;
4171 u32 offset, last_msr;
4172
4173 switch (msr) {
4174 case MSR_IA32_P5_MC_ADDR:
4175 case MSR_IA32_P5_MC_TYPE:
4176 data = 0;
4177 break;
4178 case MSR_IA32_MCG_CAP:
4179 data = vcpu->arch.mcg_cap;
4180 break;
4181 case MSR_IA32_MCG_CTL:
4182 if (!(mcg_cap & MCG_CTL_P) && !host)
4183 return 1;
4184 data = vcpu->arch.mcg_ctl;
4185 break;
4186 case MSR_IA32_MCG_STATUS:
4187 data = vcpu->arch.mcg_status;
4188 break;
4189 case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
4190 last_msr = MSR_IA32_MCx_CTL2(bank_num) - 1;
4191 if (msr > last_msr)
4192 return 1;
4193
4194 if (!(mcg_cap & MCG_CMCI_P) && !host)
4195 return 1;
4196 offset = array_index_nospec(msr - MSR_IA32_MC0_CTL2,
4197 last_msr + 1 - MSR_IA32_MC0_CTL2);
4198 data = vcpu->arch.mci_ctl2_banks[offset];
4199 break;
4200 case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
4201 last_msr = MSR_IA32_MCx_CTL(bank_num) - 1;
4202 if (msr > last_msr)
4203 return 1;
4204
4205 offset = array_index_nospec(msr - MSR_IA32_MC0_CTL,
4206 last_msr + 1 - MSR_IA32_MC0_CTL);
4207 data = vcpu->arch.mce_banks[offset];
4208 break;
4209 default:
4210 return 1;
4211 }
4212 *pdata = data;
4213 return 0;
4214 }
4215
kvm_get_msr_common(struct kvm_vcpu * vcpu,struct msr_data * msr_info)4216 int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
4217 {
4218 switch (msr_info->index) {
4219 case MSR_IA32_PLATFORM_ID:
4220 case MSR_IA32_EBL_CR_POWERON:
4221 case MSR_IA32_LASTBRANCHFROMIP:
4222 case MSR_IA32_LASTBRANCHTOIP:
4223 case MSR_IA32_LASTINTFROMIP:
4224 case MSR_IA32_LASTINTTOIP:
4225 case MSR_AMD64_SYSCFG:
4226 case MSR_K8_TSEG_ADDR:
4227 case MSR_K8_TSEG_MASK:
4228 case MSR_VM_HSAVE_PA:
4229 case MSR_K8_INT_PENDING_MSG:
4230 case MSR_AMD64_NB_CFG:
4231 case MSR_FAM10H_MMIO_CONF_BASE:
4232 case MSR_AMD64_BU_CFG2:
4233 case MSR_IA32_PERF_CTL:
4234 case MSR_AMD64_DC_CFG:
4235 case MSR_AMD64_TW_CFG:
4236 case MSR_F15H_EX_CFG:
4237 /*
4238 * Intel Sandy Bridge CPUs must support the RAPL (running average power
4239 * limit) MSRs. Just return 0, as we do not want to expose the host
4240 * data here. Do not conditionalize this on CPUID, as KVM does not do
4241 * so for existing CPU-specific MSRs.
4242 */
4243 case MSR_RAPL_POWER_UNIT:
4244 case MSR_PP0_ENERGY_STATUS: /* Power plane 0 (core) */
4245 case MSR_PP1_ENERGY_STATUS: /* Power plane 1 (graphics uncore) */
4246 case MSR_PKG_ENERGY_STATUS: /* Total package */
4247 case MSR_DRAM_ENERGY_STATUS: /* DRAM controller */
4248 msr_info->data = 0;
4249 break;
4250 case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3:
4251 case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3:
4252 case MSR_P6_PERFCTR0 ... MSR_P6_PERFCTR1:
4253 case MSR_P6_EVNTSEL0 ... MSR_P6_EVNTSEL1:
4254 if (kvm_pmu_is_valid_msr(vcpu, msr_info->index))
4255 return kvm_pmu_get_msr(vcpu, msr_info);
4256 msr_info->data = 0;
4257 break;
4258 case MSR_IA32_UCODE_REV:
4259 msr_info->data = vcpu->arch.microcode_version;
4260 break;
4261 case MSR_IA32_ARCH_CAPABILITIES:
4262 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_ARCH_CAPABILITIES))
4263 return KVM_MSR_RET_UNSUPPORTED;
4264 msr_info->data = vcpu->arch.arch_capabilities;
4265 break;
4266 case MSR_IA32_PERF_CAPABILITIES:
4267 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_PDCM))
4268 return KVM_MSR_RET_UNSUPPORTED;
4269 msr_info->data = vcpu->arch.perf_capabilities;
4270 break;
4271 case MSR_IA32_POWER_CTL:
4272 msr_info->data = vcpu->arch.msr_ia32_power_ctl;
4273 break;
4274 case MSR_IA32_TSC: {
4275 /*
4276 * Intel SDM states that MSR_IA32_TSC read adds the TSC offset
4277 * even when not intercepted. AMD manual doesn't explicitly
4278 * state this but appears to behave the same.
4279 *
4280 * On userspace reads and writes, however, we unconditionally
4281 * return L1's TSC value to ensure backwards-compatible
4282 * behavior for migration.
4283 */
4284 u64 offset, ratio;
4285
4286 if (msr_info->host_initiated) {
4287 offset = vcpu->arch.l1_tsc_offset;
4288 ratio = vcpu->arch.l1_tsc_scaling_ratio;
4289 } else {
4290 offset = vcpu->arch.tsc_offset;
4291 ratio = vcpu->arch.tsc_scaling_ratio;
4292 }
4293
4294 msr_info->data = kvm_scale_tsc(rdtsc(), ratio) + offset;
4295 break;
4296 }
4297 case MSR_IA32_CR_PAT:
4298 msr_info->data = vcpu->arch.pat;
4299 break;
4300 case MSR_MTRRcap:
4301 case MTRRphysBase_MSR(0) ... MSR_MTRRfix4K_F8000:
4302 case MSR_MTRRdefType:
4303 return kvm_mtrr_get_msr(vcpu, msr_info->index, &msr_info->data);
4304 case 0xcd: /* fsb frequency */
4305 msr_info->data = 3;
4306 break;
4307 /*
4308 * MSR_EBC_FREQUENCY_ID
4309 * Conservative value valid for even the basic CPU models.
4310 * Models 0,1: 000 in bits 23:21 indicating a bus speed of
4311 * 100MHz, model 2 000 in bits 18:16 indicating 100MHz,
4312 * and 266MHz for model 3, or 4. Set Core Clock
4313 * Frequency to System Bus Frequency Ratio to 1 (bits
4314 * 31:24) even though these are only valid for CPU
4315 * models > 2, however guests may end up dividing or
4316 * multiplying by zero otherwise.
4317 */
4318 case MSR_EBC_FREQUENCY_ID:
4319 msr_info->data = 1 << 24;
4320 break;
4321 case MSR_IA32_APICBASE:
4322 msr_info->data = vcpu->arch.apic_base;
4323 break;
4324 case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
4325 return kvm_x2apic_msr_read(vcpu, msr_info->index, &msr_info->data);
4326 case MSR_IA32_TSC_DEADLINE:
4327 msr_info->data = kvm_get_lapic_tscdeadline_msr(vcpu);
4328 break;
4329 case MSR_IA32_TSC_ADJUST:
4330 msr_info->data = (u64)vcpu->arch.ia32_tsc_adjust_msr;
4331 break;
4332 case MSR_IA32_MISC_ENABLE:
4333 msr_info->data = vcpu->arch.ia32_misc_enable_msr;
4334 break;
4335 case MSR_IA32_SMBASE:
4336 if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated)
4337 return 1;
4338 msr_info->data = vcpu->arch.smbase;
4339 break;
4340 case MSR_SMI_COUNT:
4341 msr_info->data = vcpu->arch.smi_count;
4342 break;
4343 case MSR_IA32_PERF_STATUS:
4344 /* TSC increment by tick */
4345 msr_info->data = 1000ULL;
4346 /* CPU multiplier */
4347 msr_info->data |= (((uint64_t)4ULL) << 40);
4348 break;
4349 case MSR_EFER:
4350 msr_info->data = vcpu->arch.efer;
4351 break;
4352 case MSR_KVM_WALL_CLOCK:
4353 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
4354 return 1;
4355
4356 msr_info->data = vcpu->kvm->arch.wall_clock;
4357 break;
4358 case MSR_KVM_WALL_CLOCK_NEW:
4359 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
4360 return 1;
4361
4362 msr_info->data = vcpu->kvm->arch.wall_clock;
4363 break;
4364 case MSR_KVM_SYSTEM_TIME:
4365 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
4366 return 1;
4367
4368 msr_info->data = vcpu->arch.time;
4369 break;
4370 case MSR_KVM_SYSTEM_TIME_NEW:
4371 if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
4372 return 1;
4373
4374 msr_info->data = vcpu->arch.time;
4375 break;
4376 case MSR_KVM_ASYNC_PF_EN:
4377 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
4378 return 1;
4379
4380 msr_info->data = vcpu->arch.apf.msr_en_val;
4381 break;
4382 case MSR_KVM_ASYNC_PF_INT:
4383 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4384 return 1;
4385
4386 msr_info->data = vcpu->arch.apf.msr_int_val;
4387 break;
4388 case MSR_KVM_ASYNC_PF_ACK:
4389 if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4390 return 1;
4391
4392 msr_info->data = 0;
4393 break;
4394 case MSR_KVM_STEAL_TIME:
4395 if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME))
4396 return 1;
4397
4398 msr_info->data = vcpu->arch.st.msr_val;
4399 break;
4400 case MSR_KVM_PV_EOI_EN:
4401 if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI))
4402 return 1;
4403
4404 msr_info->data = vcpu->arch.pv_eoi.msr_val;
4405 break;
4406 case MSR_KVM_POLL_CONTROL:
4407 if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL))
4408 return 1;
4409
4410 msr_info->data = vcpu->arch.msr_kvm_poll_control;
4411 break;
4412 case MSR_IA32_P5_MC_ADDR:
4413 case MSR_IA32_P5_MC_TYPE:
4414 case MSR_IA32_MCG_CAP:
4415 case MSR_IA32_MCG_CTL:
4416 case MSR_IA32_MCG_STATUS:
4417 case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
4418 case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
4419 return get_msr_mce(vcpu, msr_info->index, &msr_info->data,
4420 msr_info->host_initiated);
4421 case MSR_IA32_XSS:
4422 if (!msr_info->host_initiated &&
4423 !guest_cpuid_has(vcpu, X86_FEATURE_XSAVES))
4424 return 1;
4425 msr_info->data = vcpu->arch.ia32_xss;
4426 break;
4427 case MSR_K7_CLK_CTL:
4428 /*
4429 * Provide expected ramp-up count for K7. All other
4430 * are set to zero, indicating minimum divisors for
4431 * every field.
4432 *
4433 * This prevents guest kernels on AMD host with CPU
4434 * type 6, model 8 and higher from exploding due to
4435 * the rdmsr failing.
4436 */
4437 msr_info->data = 0x20000000;
4438 break;
4439 #ifdef CONFIG_KVM_HYPERV
4440 case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
4441 case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
4442 case HV_X64_MSR_SYNDBG_OPTIONS:
4443 case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
4444 case HV_X64_MSR_CRASH_CTL:
4445 case HV_X64_MSR_STIMER0_CONFIG ... HV_X64_MSR_STIMER3_COUNT:
4446 case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
4447 case HV_X64_MSR_TSC_EMULATION_CONTROL:
4448 case HV_X64_MSR_TSC_EMULATION_STATUS:
4449 case HV_X64_MSR_TSC_INVARIANT_CONTROL:
4450 return kvm_hv_get_msr_common(vcpu,
4451 msr_info->index, &msr_info->data,
4452 msr_info->host_initiated);
4453 #endif
4454 case MSR_IA32_BBL_CR_CTL3:
4455 /* This legacy MSR exists but isn't fully documented in current
4456 * silicon. It is however accessed by winxp in very narrow
4457 * scenarios where it sets bit #19, itself documented as
4458 * a "reserved" bit. Best effort attempt to source coherent
4459 * read data here should the balance of the register be
4460 * interpreted by the guest:
4461 *
4462 * L2 cache control register 3: 64GB range, 256KB size,
4463 * enabled, latency 0x1, configured
4464 */
4465 msr_info->data = 0xbe702111;
4466 break;
4467 case MSR_AMD64_OSVW_ID_LENGTH:
4468 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_OSVW))
4469 return 1;
4470 msr_info->data = vcpu->arch.osvw.length;
4471 break;
4472 case MSR_AMD64_OSVW_STATUS:
4473 if (!guest_cpu_cap_has(vcpu, X86_FEATURE_OSVW))
4474 return 1;
4475 msr_info->data = vcpu->arch.osvw.status;
4476 break;
4477 case MSR_PLATFORM_INFO:
4478 if (!msr_info->host_initiated &&
4479 !vcpu->kvm->arch.guest_can_read_msr_platform_info)
4480 return 1;
4481 msr_info->data = vcpu->arch.msr_platform_info;
4482 break;
4483 case MSR_MISC_FEATURES_ENABLES:
4484 msr_info->data = vcpu->arch.msr_misc_features_enables;
4485 break;
4486 case MSR_K7_HWCR:
4487 msr_info->data = vcpu->arch.msr_hwcr;
4488 break;
4489 #ifdef CONFIG_X86_64
4490 case MSR_IA32_XFD:
4491 if (!msr_info->host_initiated &&
4492 !guest_cpu_cap_has(vcpu, X86_FEATURE_XFD))
4493 return 1;
4494
4495 msr_info->data = vcpu->arch.guest_fpu.fpstate->xfd;
4496 break;
4497 case MSR_IA32_XFD_ERR:
4498 if (!msr_info->host_initiated &&
4499 !guest_cpu_cap_has(vcpu, X86_FEATURE_XFD))
4500 return 1;
4501
4502 msr_info->data = vcpu->arch.guest_fpu.xfd_err;
4503 break;
4504 #endif
4505 default:
4506 if (kvm_pmu_is_valid_msr(vcpu, msr_info->index))
4507 return kvm_pmu_get_msr(vcpu, msr_info);
4508
4509 return KVM_MSR_RET_UNSUPPORTED;
4510 }
4511 return 0;
4512 }
4513 EXPORT_SYMBOL_GPL(kvm_get_msr_common);
4514
4515 /*
4516 * Read or write a bunch of msrs. All parameters are kernel addresses.
4517 *
4518 * @return number of msrs set successfully.
4519 */
__msr_io(struct kvm_vcpu * vcpu,struct kvm_msrs * msrs,struct kvm_msr_entry * entries,int (* do_msr)(struct kvm_vcpu * vcpu,unsigned index,u64 * data))4520 static int __msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs *msrs,
4521 struct kvm_msr_entry *entries,
4522 int (*do_msr)(struct kvm_vcpu *vcpu,
4523 unsigned index, u64 *data))
4524 {
4525 int i;
4526
4527 for (i = 0; i < msrs->nmsrs; ++i)
4528 if (do_msr(vcpu, entries[i].index, &entries[i].data))
4529 break;
4530
4531 return i;
4532 }
4533
4534 /*
4535 * Read or write a bunch of msrs. Parameters are user addresses.
4536 *
4537 * @return number of msrs set successfully.
4538 */
msr_io(struct kvm_vcpu * vcpu,struct kvm_msrs __user * user_msrs,int (* do_msr)(struct kvm_vcpu * vcpu,unsigned index,u64 * data),int writeback)4539 static int msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs __user *user_msrs,
4540 int (*do_msr)(struct kvm_vcpu *vcpu,
4541 unsigned index, u64 *data),
4542 int writeback)
4543 {
4544 struct kvm_msrs msrs;
4545 struct kvm_msr_entry *entries;
4546 unsigned size;
4547 int r;
4548
4549 r = -EFAULT;
4550 if (copy_from_user(&msrs, user_msrs, sizeof(msrs)))
4551 goto out;
4552
4553 r = -E2BIG;
4554 if (msrs.nmsrs >= MAX_IO_MSRS)
4555 goto out;
4556
4557 size = sizeof(struct kvm_msr_entry) * msrs.nmsrs;
4558 entries = memdup_user(user_msrs->entries, size);
4559 if (IS_ERR(entries)) {
4560 r = PTR_ERR(entries);
4561 goto out;
4562 }
4563
4564 r = __msr_io(vcpu, &msrs, entries, do_msr);
4565
4566 if (writeback && copy_to_user(user_msrs->entries, entries, size))
4567 r = -EFAULT;
4568
4569 kfree(entries);
4570 out:
4571 return r;
4572 }
4573
kvm_can_mwait_in_guest(void)4574 static inline bool kvm_can_mwait_in_guest(void)
4575 {
4576 return boot_cpu_has(X86_FEATURE_MWAIT) &&
4577 !boot_cpu_has_bug(X86_BUG_MONITOR) &&
4578 boot_cpu_has(X86_FEATURE_ARAT);
4579 }
4580
kvm_get_allowed_disable_exits(void)4581 static u64 kvm_get_allowed_disable_exits(void)
4582 {
4583 u64 r = KVM_X86_DISABLE_EXITS_PAUSE;
4584
4585 if (boot_cpu_has(X86_FEATURE_APERFMPERF))
4586 r |= KVM_X86_DISABLE_EXITS_APERFMPERF;
4587
4588 if (!mitigate_smt_rsb) {
4589 r |= KVM_X86_DISABLE_EXITS_HLT |
4590 KVM_X86_DISABLE_EXITS_CSTATE;
4591
4592 if (kvm_can_mwait_in_guest())
4593 r |= KVM_X86_DISABLE_EXITS_MWAIT;
4594 }
4595 return r;
4596 }
4597
4598 #ifdef CONFIG_KVM_HYPERV
kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu * vcpu,struct kvm_cpuid2 __user * cpuid_arg)4599 static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu,
4600 struct kvm_cpuid2 __user *cpuid_arg)
4601 {
4602 struct kvm_cpuid2 cpuid;
4603 int r;
4604
4605 r = -EFAULT;
4606 if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
4607 return r;
4608
4609 r = kvm_get_hv_cpuid(vcpu, &cpuid, cpuid_arg->entries);
4610 if (r)
4611 return r;
4612
4613 r = -EFAULT;
4614 if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
4615 return r;
4616
4617 return 0;
4618 }
4619 #endif
4620
kvm_is_vm_type_supported(unsigned long type)4621 static bool kvm_is_vm_type_supported(unsigned long type)
4622 {
4623 return type < 32 && (kvm_caps.supported_vm_types & BIT(type));
4624 }
4625
kvm_sync_valid_fields(struct kvm * kvm)4626 static inline u64 kvm_sync_valid_fields(struct kvm *kvm)
4627 {
4628 return kvm && kvm->arch.has_protected_state ? 0 : KVM_SYNC_X86_VALID_FIELDS;
4629 }
4630
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)4631 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
4632 {
4633 int r = 0;
4634
4635 switch (ext) {
4636 case KVM_CAP_IRQCHIP:
4637 case KVM_CAP_HLT:
4638 case KVM_CAP_MMU_SHADOW_CACHE_CONTROL:
4639 case KVM_CAP_SET_TSS_ADDR:
4640 case KVM_CAP_EXT_CPUID:
4641 case KVM_CAP_EXT_EMUL_CPUID:
4642 case KVM_CAP_CLOCKSOURCE:
4643 #ifdef CONFIG_KVM_IOAPIC
4644 case KVM_CAP_PIT:
4645 case KVM_CAP_PIT2:
4646 case KVM_CAP_PIT_STATE2:
4647 case KVM_CAP_REINJECT_CONTROL:
4648 #endif
4649 case KVM_CAP_NOP_IO_DELAY:
4650 case KVM_CAP_MP_STATE:
4651 case KVM_CAP_SYNC_MMU:
4652 case KVM_CAP_USER_NMI:
4653 case KVM_CAP_IRQ_INJECT_STATUS:
4654 case KVM_CAP_IOEVENTFD:
4655 case KVM_CAP_IOEVENTFD_NO_LENGTH:
4656
4657 case KVM_CAP_SET_IDENTITY_MAP_ADDR:
4658 case KVM_CAP_VCPU_EVENTS:
4659 #ifdef CONFIG_KVM_HYPERV
4660 case KVM_CAP_HYPERV:
4661 case KVM_CAP_HYPERV_VAPIC:
4662 case KVM_CAP_HYPERV_SPIN:
4663 case KVM_CAP_HYPERV_TIME:
4664 case KVM_CAP_HYPERV_SYNIC:
4665 case KVM_CAP_HYPERV_SYNIC2:
4666 case KVM_CAP_HYPERV_VP_INDEX:
4667 case KVM_CAP_HYPERV_EVENTFD:
4668 case KVM_CAP_HYPERV_TLBFLUSH:
4669 case KVM_CAP_HYPERV_SEND_IPI:
4670 case KVM_CAP_HYPERV_CPUID:
4671 case KVM_CAP_HYPERV_ENFORCE_CPUID:
4672 case KVM_CAP_SYS_HYPERV_CPUID:
4673 #endif
4674 case KVM_CAP_PCI_SEGMENT:
4675 case KVM_CAP_DEBUGREGS:
4676 case KVM_CAP_X86_ROBUST_SINGLESTEP:
4677 case KVM_CAP_XSAVE:
4678 case KVM_CAP_ASYNC_PF:
4679 case KVM_CAP_ASYNC_PF_INT:
4680 case KVM_CAP_GET_TSC_KHZ:
4681 case KVM_CAP_KVMCLOCK_CTRL:
4682 case KVM_CAP_IOAPIC_POLARITY_IGNORED:
4683 case KVM_CAP_TSC_DEADLINE_TIMER:
4684 case KVM_CAP_DISABLE_QUIRKS:
4685 case KVM_CAP_SET_BOOT_CPU_ID:
4686 case KVM_CAP_SPLIT_IRQCHIP:
4687 case KVM_CAP_IMMEDIATE_EXIT:
4688 case KVM_CAP_PMU_EVENT_FILTER:
4689 case KVM_CAP_PMU_EVENT_MASKED_EVENTS:
4690 case KVM_CAP_GET_MSR_FEATURES:
4691 case KVM_CAP_MSR_PLATFORM_INFO:
4692 case KVM_CAP_EXCEPTION_PAYLOAD:
4693 case KVM_CAP_X86_TRIPLE_FAULT_EVENT:
4694 case KVM_CAP_SET_GUEST_DEBUG:
4695 case KVM_CAP_LAST_CPU:
4696 case KVM_CAP_X86_USER_SPACE_MSR:
4697 case KVM_CAP_X86_MSR_FILTER:
4698 case KVM_CAP_ENFORCE_PV_FEATURE_CPUID:
4699 #ifdef CONFIG_X86_SGX_KVM
4700 case KVM_CAP_SGX_ATTRIBUTE:
4701 #endif
4702 case KVM_CAP_VM_COPY_ENC_CONTEXT_FROM:
4703 case KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM:
4704 case KVM_CAP_SREGS2:
4705 case KVM_CAP_EXIT_ON_EMULATION_FAILURE:
4706 case KVM_CAP_VCPU_ATTRIBUTES:
4707 case KVM_CAP_SYS_ATTRIBUTES:
4708 case KVM_CAP_VAPIC:
4709 case KVM_CAP_ENABLE_CAP:
4710 case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES:
4711 case KVM_CAP_IRQFD_RESAMPLE:
4712 case KVM_CAP_MEMORY_FAULT_INFO:
4713 case KVM_CAP_X86_GUEST_MODE:
4714 r = 1;
4715 break;
4716 case KVM_CAP_PRE_FAULT_MEMORY:
4717 r = tdp_enabled;
4718 break;
4719 case KVM_CAP_X86_APIC_BUS_CYCLES_NS:
4720 r = APIC_BUS_CYCLE_NS_DEFAULT;
4721 break;
4722 case KVM_CAP_EXIT_HYPERCALL:
4723 r = KVM_EXIT_HYPERCALL_VALID_MASK;
4724 break;
4725 case KVM_CAP_SET_GUEST_DEBUG2:
4726 return KVM_GUESTDBG_VALID_MASK;
4727 #ifdef CONFIG_KVM_XEN
4728 case KVM_CAP_XEN_HVM:
4729 r = KVM_XEN_HVM_CONFIG_HYPERCALL_MSR |
4730 KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL |
4731 KVM_XEN_HVM_CONFIG_SHARED_INFO |
4732 KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL |
4733 KVM_XEN_HVM_CONFIG_EVTCHN_SEND |
4734 KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE |
4735 KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA;
4736 if (sched_info_on())
4737 r |= KVM_XEN_HVM_CONFIG_RUNSTATE |
4738 KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG;
4739 break;
4740 #endif
4741 case KVM_CAP_SYNC_REGS:
4742 r = kvm_sync_valid_fields(kvm);
4743 break;
4744 case KVM_CAP_ADJUST_CLOCK:
4745 r = KVM_CLOCK_VALID_FLAGS;
4746 break;
4747 case KVM_CAP_X86_DISABLE_EXITS:
4748 r = kvm_get_allowed_disable_exits();
4749 break;
4750 case KVM_CAP_X86_SMM:
4751 if (!IS_ENABLED(CONFIG_KVM_SMM))
4752 break;
4753
4754 /* SMBASE is usually relocated above 1M on modern chipsets,
4755 * and SMM handlers might indeed rely on 4G segment limits,
4756 * so do not report SMM to be available if real mode is
4757 * emulated via vm86 mode. Still, do not go to great lengths
4758 * to avoid userspace's usage of the feature, because it is a
4759 * fringe case that is not enabled except via specific settings
4760 * of the module parameters.
4761 */
4762 r = kvm_x86_call(has_emulated_msr)(kvm, MSR_IA32_SMBASE);
4763 break;
4764 case KVM_CAP_NR_VCPUS:
4765 r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
4766 break;
4767 case KVM_CAP_MAX_VCPUS:
4768 r = KVM_MAX_VCPUS;
4769 if (kvm)
4770 r = kvm->max_vcpus;
4771 break;
4772 case KVM_CAP_MAX_VCPU_ID:
4773 r = KVM_MAX_VCPU_IDS;
4774 break;
4775 case KVM_CAP_PV_MMU: /* obsolete */
4776 r = 0;
4777 break;
4778 case KVM_CAP_MCE:
4779 r = KVM_MAX_MCE_BANKS;
4780 break;
4781 case KVM_CAP_XCRS:
4782 r = boot_cpu_has(X86_FEATURE_XSAVE);
4783 break;
4784 case KVM_CAP_TSC_CONTROL:
4785 case KVM_CAP_VM_TSC_CONTROL:
4786 r = kvm_caps.has_tsc_control;
4787 break;
4788 case KVM_CAP_X2APIC_API:
4789 r = KVM_X2APIC_API_VALID_FLAGS;
4790 break;
4791 case KVM_CAP_NESTED_STATE:
4792 r = kvm_x86_ops.nested_ops->get_state ?
4793 kvm_x86_ops.nested_ops->get_state(NULL, NULL, 0) : 0;
4794 break;
4795 #ifdef CONFIG_KVM_HYPERV
4796 case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
4797 r = kvm_x86_ops.enable_l2_tlb_flush != NULL;
4798 break;
4799 case KVM_CAP_HYPERV_ENLIGHTENED_VMCS:
4800 r = kvm_x86_ops.nested_ops->enable_evmcs != NULL;
4801 break;
4802 #endif
4803 case KVM_CAP_SMALLER_MAXPHYADDR:
4804 r = (int) allow_smaller_maxphyaddr;
4805 break;
4806 case KVM_CAP_STEAL_TIME:
4807 r = sched_info_on();
4808 break;
4809 case KVM_CAP_X86_BUS_LOCK_EXIT:
4810 if (kvm_caps.has_bus_lock_exit)
4811 r = KVM_BUS_LOCK_DETECTION_OFF |
4812 KVM_BUS_LOCK_DETECTION_EXIT;
4813 else
4814 r = 0;
4815 break;
4816 case KVM_CAP_XSAVE2: {
4817 r = xstate_required_size(kvm_get_filtered_xcr0(), false);
4818 if (r < sizeof(struct kvm_xsave))
4819 r = sizeof(struct kvm_xsave);
4820 break;
4821 }
4822 case KVM_CAP_PMU_CAPABILITY:
4823 r = enable_pmu ? KVM_CAP_PMU_VALID_MASK : 0;
4824 break;
4825 case KVM_CAP_DISABLE_QUIRKS2:
4826 r = kvm_caps.supported_quirks;
4827 break;
4828 case KVM_CAP_X86_NOTIFY_VMEXIT:
4829 r = kvm_caps.has_notify_vmexit;
4830 break;
4831 case KVM_CAP_VM_TYPES:
4832 r = kvm_caps.supported_vm_types;
4833 break;
4834 case KVM_CAP_READONLY_MEM:
4835 r = kvm ? kvm_arch_has_readonly_mem(kvm) : 1;
4836 break;
4837 default:
4838 break;
4839 }
4840 return r;
4841 }
4842
__kvm_x86_dev_get_attr(struct kvm_device_attr * attr,u64 * val)4843 static int __kvm_x86_dev_get_attr(struct kvm_device_attr *attr, u64 *val)
4844 {
4845 if (attr->group) {
4846 if (kvm_x86_ops.dev_get_attr)
4847 return kvm_x86_call(dev_get_attr)(attr->group, attr->attr, val);
4848 return -ENXIO;
4849 }
4850
4851 switch (attr->attr) {
4852 case KVM_X86_XCOMP_GUEST_SUPP:
4853 *val = kvm_caps.supported_xcr0;
4854 return 0;
4855 default:
4856 return -ENXIO;
4857 }
4858 }
4859
kvm_x86_dev_get_attr(struct kvm_device_attr * attr)4860 static int kvm_x86_dev_get_attr(struct kvm_device_attr *attr)
4861 {
4862 u64 __user *uaddr = u64_to_user_ptr(attr->addr);
4863 int r;
4864 u64 val;
4865
4866 r = __kvm_x86_dev_get_attr(attr, &val);
4867 if (r < 0)
4868 return r;
4869
4870 if (put_user(val, uaddr))
4871 return -EFAULT;
4872
4873 return 0;
4874 }
4875
kvm_x86_dev_has_attr(struct kvm_device_attr * attr)4876 static int kvm_x86_dev_has_attr(struct kvm_device_attr *attr)
4877 {
4878 u64 val;
4879
4880 return __kvm_x86_dev_get_attr(attr, &val);
4881 }
4882
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)4883 long kvm_arch_dev_ioctl(struct file *filp,
4884 unsigned int ioctl, unsigned long arg)
4885 {
4886 void __user *argp = (void __user *)arg;
4887 long r;
4888
4889 switch (ioctl) {
4890 case KVM_GET_MSR_INDEX_LIST: {
4891 struct kvm_msr_list __user *user_msr_list = argp;
4892 struct kvm_msr_list msr_list;
4893 unsigned n;
4894
4895 r = -EFAULT;
4896 if (copy_from_user(&msr_list, user_msr_list, sizeof(msr_list)))
4897 goto out;
4898 n = msr_list.nmsrs;
4899 msr_list.nmsrs = num_msrs_to_save + num_emulated_msrs;
4900 if (copy_to_user(user_msr_list, &msr_list, sizeof(msr_list)))
4901 goto out;
4902 r = -E2BIG;
4903 if (n < msr_list.nmsrs)
4904 goto out;
4905 r = -EFAULT;
4906 if (copy_to_user(user_msr_list->indices, &msrs_to_save,
4907 num_msrs_to_save * sizeof(u32)))
4908 goto out;
4909 if (copy_to_user(user_msr_list->indices + num_msrs_to_save,
4910 &emulated_msrs,
4911 num_emulated_msrs * sizeof(u32)))
4912 goto out;
4913 r = 0;
4914 break;
4915 }
4916 case KVM_GET_SUPPORTED_CPUID:
4917 case KVM_GET_EMULATED_CPUID: {
4918 struct kvm_cpuid2 __user *cpuid_arg = argp;
4919 struct kvm_cpuid2 cpuid;
4920
4921 r = -EFAULT;
4922 if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
4923 goto out;
4924
4925 r = kvm_dev_ioctl_get_cpuid(&cpuid, cpuid_arg->entries,
4926 ioctl);
4927 if (r)
4928 goto out;
4929
4930 r = -EFAULT;
4931 if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
4932 goto out;
4933 r = 0;
4934 break;
4935 }
4936 case KVM_X86_GET_MCE_CAP_SUPPORTED:
4937 r = -EFAULT;
4938 if (copy_to_user(argp, &kvm_caps.supported_mce_cap,
4939 sizeof(kvm_caps.supported_mce_cap)))
4940 goto out;
4941 r = 0;
4942 break;
4943 case KVM_GET_MSR_FEATURE_INDEX_LIST: {
4944 struct kvm_msr_list __user *user_msr_list = argp;
4945 struct kvm_msr_list msr_list;
4946 unsigned int n;
4947
4948 r = -EFAULT;
4949 if (copy_from_user(&msr_list, user_msr_list, sizeof(msr_list)))
4950 goto out;
4951 n = msr_list.nmsrs;
4952 msr_list.nmsrs = num_msr_based_features;
4953 if (copy_to_user(user_msr_list, &msr_list, sizeof(msr_list)))
4954 goto out;
4955 r = -E2BIG;
4956 if (n < msr_list.nmsrs)
4957 goto out;
4958 r = -EFAULT;
4959 if (copy_to_user(user_msr_list->indices, &msr_based_features,
4960 num_msr_based_features * sizeof(u32)))
4961 goto out;
4962 r = 0;
4963 break;
4964 }
4965 case KVM_GET_MSRS:
4966 r = msr_io(NULL, argp, do_get_feature_msr, 1);
4967 break;
4968 #ifdef CONFIG_KVM_HYPERV
4969 case KVM_GET_SUPPORTED_HV_CPUID:
4970 r = kvm_ioctl_get_supported_hv_cpuid(NULL, argp);
4971 break;
4972 #endif
4973 case KVM_GET_DEVICE_ATTR: {
4974 struct kvm_device_attr attr;
4975 r = -EFAULT;
4976 if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
4977 break;
4978 r = kvm_x86_dev_get_attr(&attr);
4979 break;
4980 }
4981 case KVM_HAS_DEVICE_ATTR: {
4982 struct kvm_device_attr attr;
4983 r = -EFAULT;
4984 if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
4985 break;
4986 r = kvm_x86_dev_has_attr(&attr);
4987 break;
4988 }
4989 default:
4990 r = -EINVAL;
4991 break;
4992 }
4993 out:
4994 return r;
4995 }
4996
need_emulate_wbinvd(struct kvm_vcpu * vcpu)4997 static bool need_emulate_wbinvd(struct kvm_vcpu *vcpu)
4998 {
4999 return kvm_arch_has_noncoherent_dma(vcpu->kvm);
5000 }
5001
5002 static DEFINE_PER_CPU(struct kvm_vcpu *, last_vcpu);
5003
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)5004 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
5005 {
5006 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
5007
5008 vcpu->arch.l1tf_flush_l1d = true;
5009
5010 if (vcpu->scheduled_out && pmu->version && pmu->event_count) {
5011 pmu->need_cleanup = true;
5012 kvm_make_request(KVM_REQ_PMU, vcpu);
5013 }
5014
5015 /* Address WBINVD may be executed by guest */
5016 if (need_emulate_wbinvd(vcpu)) {
5017 if (kvm_x86_call(has_wbinvd_exit)())
5018 cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask);
5019 else if (vcpu->cpu != -1 && vcpu->cpu != cpu)
5020 wbinvd_on_cpu(vcpu->cpu);
5021 }
5022
5023 kvm_x86_call(vcpu_load)(vcpu, cpu);
5024
5025 if (vcpu != per_cpu(last_vcpu, cpu)) {
5026 /*
5027 * Flush the branch predictor when switching vCPUs on the same
5028 * physical CPU, as each vCPU needs its own branch prediction
5029 * domain. No IBPB is needed when switching between L1 and L2
5030 * on the same vCPU unless IBRS is advertised to the vCPU; that
5031 * is handled on the nested VM-Exit path.
5032 */
5033 if (static_branch_likely(&switch_vcpu_ibpb))
5034 indirect_branch_prediction_barrier();
5035 per_cpu(last_vcpu, cpu) = vcpu;
5036 }
5037
5038 /* Save host pkru register if supported */
5039 vcpu->arch.host_pkru = read_pkru();
5040
5041 /* Apply any externally detected TSC adjustments (due to suspend) */
5042 if (unlikely(vcpu->arch.tsc_offset_adjustment)) {
5043 adjust_tsc_offset_host(vcpu, vcpu->arch.tsc_offset_adjustment);
5044 vcpu->arch.tsc_offset_adjustment = 0;
5045 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
5046 }
5047
5048 if (unlikely(vcpu->cpu != cpu) || kvm_check_tsc_unstable()) {
5049 s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 :
5050 rdtsc() - vcpu->arch.last_host_tsc;
5051 if (tsc_delta < 0)
5052 mark_tsc_unstable("KVM discovered backwards TSC");
5053
5054 if (kvm_check_tsc_unstable()) {
5055 u64 offset = kvm_compute_l1_tsc_offset(vcpu,
5056 vcpu->arch.last_guest_tsc);
5057 kvm_vcpu_write_tsc_offset(vcpu, offset);
5058 if (!vcpu->arch.guest_tsc_protected)
5059 vcpu->arch.tsc_catchup = 1;
5060 }
5061
5062 if (kvm_lapic_hv_timer_in_use(vcpu))
5063 kvm_lapic_restart_hv_timer(vcpu);
5064
5065 /*
5066 * On a host with synchronized TSC, there is no need to update
5067 * kvmclock on vcpu->cpu migration
5068 */
5069 if (!vcpu->kvm->arch.use_master_clock || vcpu->cpu == -1)
5070 kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
5071 if (vcpu->cpu != cpu)
5072 kvm_make_request(KVM_REQ_MIGRATE_TIMER, vcpu);
5073 vcpu->cpu = cpu;
5074 }
5075
5076 kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
5077 }
5078
kvm_steal_time_set_preempted(struct kvm_vcpu * vcpu)5079 static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
5080 {
5081 struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache;
5082 struct kvm_steal_time __user *st;
5083 struct kvm_memslots *slots;
5084 static const u8 preempted = KVM_VCPU_PREEMPTED;
5085 gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS;
5086
5087 /*
5088 * The vCPU can be marked preempted if and only if the VM-Exit was on
5089 * an instruction boundary and will not trigger guest emulation of any
5090 * kind (see vcpu_run). Vendor specific code controls (conservatively)
5091 * when this is true, for example allowing the vCPU to be marked
5092 * preempted if and only if the VM-Exit was due to a host interrupt.
5093 */
5094 if (!vcpu->arch.at_instruction_boundary) {
5095 vcpu->stat.preemption_other++;
5096 return;
5097 }
5098
5099 vcpu->stat.preemption_reported++;
5100 if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
5101 return;
5102
5103 if (vcpu->arch.st.preempted)
5104 return;
5105
5106 /* This happens on process exit */
5107 if (unlikely(current->mm != vcpu->kvm->mm))
5108 return;
5109
5110 slots = kvm_memslots(vcpu->kvm);
5111
5112 if (unlikely(slots->generation != ghc->generation ||
5113 gpa != ghc->gpa ||
5114 kvm_is_error_hva(ghc->hva) || !ghc->memslot))
5115 return;
5116
5117 st = (struct kvm_steal_time __user *)ghc->hva;
5118 BUILD_BUG_ON(sizeof(st->preempted) != sizeof(preempted));
5119
5120 if (!copy_to_user_nofault(&st->preempted, &preempted, sizeof(preempted)))
5121 vcpu->arch.st.preempted = KVM_VCPU_PREEMPTED;
5122
5123 mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
5124 }
5125
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)5126 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
5127 {
5128 int idx;
5129
5130 if (vcpu->preempted) {
5131 /*
5132 * Assume protected guests are in-kernel. Inefficient yielding
5133 * due to false positives is preferable to never yielding due
5134 * to false negatives.
5135 */
5136 vcpu->arch.preempted_in_kernel = vcpu->arch.guest_state_protected ||
5137 !kvm_x86_call(get_cpl_no_cache)(vcpu);
5138
5139 /*
5140 * Take the srcu lock as memslots will be accessed to check the gfn
5141 * cache generation against the memslots generation.
5142 */
5143 idx = srcu_read_lock(&vcpu->kvm->srcu);
5144 if (kvm_xen_msr_enabled(vcpu->kvm))
5145 kvm_xen_runstate_set_preempted(vcpu);
5146 else
5147 kvm_steal_time_set_preempted(vcpu);
5148 srcu_read_unlock(&vcpu->kvm->srcu, idx);
5149 }
5150
5151 kvm_x86_call(vcpu_put)(vcpu);
5152 vcpu->arch.last_host_tsc = rdtsc();
5153 }
5154
kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu * vcpu,struct kvm_lapic_state * s)5155 static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
5156 struct kvm_lapic_state *s)
5157 {
5158 if (vcpu->arch.apic->guest_apic_protected)
5159 return -EINVAL;
5160
5161 kvm_x86_call(sync_pir_to_irr)(vcpu);
5162
5163 return kvm_apic_get_state(vcpu, s);
5164 }
5165
kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu * vcpu,struct kvm_lapic_state * s)5166 static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu,
5167 struct kvm_lapic_state *s)
5168 {
5169 int r;
5170
5171 if (vcpu->arch.apic->guest_apic_protected)
5172 return -EINVAL;
5173
5174 r = kvm_apic_set_state(vcpu, s);
5175 if (r)
5176 return r;
5177 update_cr8_intercept(vcpu);
5178
5179 return 0;
5180 }
5181
kvm_cpu_accept_dm_intr(struct kvm_vcpu * vcpu)5182 static int kvm_cpu_accept_dm_intr(struct kvm_vcpu *vcpu)
5183 {
5184 /*
5185 * We can accept userspace's request for interrupt injection
5186 * as long as we have a place to store the interrupt number.
5187 * The actual injection will happen when the CPU is able to
5188 * deliver the interrupt.
5189 */
5190 if (kvm_cpu_has_extint(vcpu))
5191 return false;
5192
5193 /* Acknowledging ExtINT does not happen if LINT0 is masked. */
5194 return (!lapic_in_kernel(vcpu) ||
5195 kvm_apic_accept_pic_intr(vcpu));
5196 }
5197
kvm_vcpu_ready_for_interrupt_injection(struct kvm_vcpu * vcpu)5198 static int kvm_vcpu_ready_for_interrupt_injection(struct kvm_vcpu *vcpu)
5199 {
5200 /*
5201 * Do not cause an interrupt window exit if an exception
5202 * is pending or an event needs reinjection; userspace
5203 * might want to inject the interrupt manually using KVM_SET_REGS
5204 * or KVM_SET_SREGS. For that to work, we must be at an
5205 * instruction boundary and with no events half-injected.
5206 */
5207 return (kvm_arch_interrupt_allowed(vcpu) &&
5208 kvm_cpu_accept_dm_intr(vcpu) &&
5209 !kvm_event_needs_reinjection(vcpu) &&
5210 !kvm_is_exception_pending(vcpu));
5211 }
5212
kvm_vcpu_ioctl_interrupt(struct kvm_vcpu * vcpu,struct kvm_interrupt * irq)5213 static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
5214 struct kvm_interrupt *irq)
5215 {
5216 if (irq->irq >= KVM_NR_INTERRUPTS)
5217 return -EINVAL;
5218
5219 if (!irqchip_in_kernel(vcpu->kvm)) {
5220 kvm_queue_interrupt(vcpu, irq->irq, false);
5221 kvm_make_request(KVM_REQ_EVENT, vcpu);
5222 return 0;
5223 }
5224
5225 /*
5226 * With in-kernel LAPIC, we only use this to inject EXTINT, so
5227 * fail for in-kernel 8259.
5228 */
5229 if (pic_in_kernel(vcpu->kvm))
5230 return -ENXIO;
5231
5232 if (vcpu->arch.pending_external_vector != -1)
5233 return -EEXIST;
5234
5235 vcpu->arch.pending_external_vector = irq->irq;
5236 kvm_make_request(KVM_REQ_EVENT, vcpu);
5237 return 0;
5238 }
5239
kvm_vcpu_ioctl_nmi(struct kvm_vcpu * vcpu)5240 static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu)
5241 {
5242 kvm_inject_nmi(vcpu);
5243
5244 return 0;
5245 }
5246
vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu * vcpu,struct kvm_tpr_access_ctl * tac)5247 static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu,
5248 struct kvm_tpr_access_ctl *tac)
5249 {
5250 if (tac->flags)
5251 return -EINVAL;
5252 vcpu->arch.tpr_access_reporting = !!tac->enabled;
5253 return 0;
5254 }
5255
kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu * vcpu,u64 mcg_cap)5256 static int kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu *vcpu,
5257 u64 mcg_cap)
5258 {
5259 int r;
5260 unsigned bank_num = mcg_cap & 0xff, bank;
5261
5262 r = -EINVAL;
5263 if (!bank_num || bank_num > KVM_MAX_MCE_BANKS)
5264 goto out;
5265 if (mcg_cap & ~(kvm_caps.supported_mce_cap | 0xff | 0xff0000))
5266 goto out;
5267 r = 0;
5268 vcpu->arch.mcg_cap = mcg_cap;
5269 /* Init IA32_MCG_CTL to all 1s */
5270 if (mcg_cap & MCG_CTL_P)
5271 vcpu->arch.mcg_ctl = ~(u64)0;
5272 /* Init IA32_MCi_CTL to all 1s, IA32_MCi_CTL2 to all 0s */
5273 for (bank = 0; bank < bank_num; bank++) {
5274 vcpu->arch.mce_banks[bank*4] = ~(u64)0;
5275 if (mcg_cap & MCG_CMCI_P)
5276 vcpu->arch.mci_ctl2_banks[bank] = 0;
5277 }
5278
5279 kvm_apic_after_set_mcg_cap(vcpu);
5280
5281 kvm_x86_call(setup_mce)(vcpu);
5282 out:
5283 return r;
5284 }
5285
5286 /*
5287 * Validate this is an UCNA (uncorrectable no action) error by checking the
5288 * MCG_STATUS and MCi_STATUS registers:
5289 * - none of the bits for Machine Check Exceptions are set
5290 * - both the VAL (valid) and UC (uncorrectable) bits are set
5291 * MCI_STATUS_PCC - Processor Context Corrupted
5292 * MCI_STATUS_S - Signaled as a Machine Check Exception
5293 * MCI_STATUS_AR - Software recoverable Action Required
5294 */
is_ucna(struct kvm_x86_mce * mce)5295 static bool is_ucna(struct kvm_x86_mce *mce)
5296 {
5297 return !mce->mcg_status &&
5298 !(mce->status & (MCI_STATUS_PCC | MCI_STATUS_S | MCI_STATUS_AR)) &&
5299 (mce->status & MCI_STATUS_VAL) &&
5300 (mce->status & MCI_STATUS_UC);
5301 }
5302
kvm_vcpu_x86_set_ucna(struct kvm_vcpu * vcpu,struct kvm_x86_mce * mce,u64 * banks)5303 static int kvm_vcpu_x86_set_ucna(struct kvm_vcpu *vcpu, struct kvm_x86_mce *mce, u64* banks)
5304 {
5305 u64 mcg_cap = vcpu->arch.mcg_cap;
5306
5307 banks[1] = mce->status;
5308 banks[2] = mce->addr;
5309 banks[3] = mce->misc;
5310 vcpu->arch.mcg_status = mce->mcg_status;
5311
5312 if (!(mcg_cap & MCG_CMCI_P) ||
5313 !(vcpu->arch.mci_ctl2_banks[mce->bank] & MCI_CTL2_CMCI_EN))
5314 return 0;
5315
5316 if (lapic_in_kernel(vcpu))
5317 kvm_apic_local_deliver(vcpu->arch.apic, APIC_LVTCMCI);
5318
5319 return 0;
5320 }
5321
kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu * vcpu,struct kvm_x86_mce * mce)5322 static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu,
5323 struct kvm_x86_mce *mce)
5324 {
5325 u64 mcg_cap = vcpu->arch.mcg_cap;
5326 unsigned bank_num = mcg_cap & 0xff;
5327 u64 *banks = vcpu->arch.mce_banks;
5328
5329 if (mce->bank >= bank_num || !(mce->status & MCI_STATUS_VAL))
5330 return -EINVAL;
5331
5332 banks += array_index_nospec(4 * mce->bank, 4 * bank_num);
5333
5334 if (is_ucna(mce))
5335 return kvm_vcpu_x86_set_ucna(vcpu, mce, banks);
5336
5337 /*
5338 * if IA32_MCG_CTL is not all 1s, the uncorrected error
5339 * reporting is disabled
5340 */
5341 if ((mce->status & MCI_STATUS_UC) && (mcg_cap & MCG_CTL_P) &&
5342 vcpu->arch.mcg_ctl != ~(u64)0)
5343 return 0;
5344 /*
5345 * if IA32_MCi_CTL is not all 1s, the uncorrected error
5346 * reporting is disabled for the bank
5347 */
5348 if ((mce->status & MCI_STATUS_UC) && banks[0] != ~(u64)0)
5349 return 0;
5350 if (mce->status & MCI_STATUS_UC) {
5351 if ((vcpu->arch.mcg_status & MCG_STATUS_MCIP) ||
5352 !kvm_is_cr4_bit_set(vcpu, X86_CR4_MCE)) {
5353 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5354 return 0;
5355 }
5356 if (banks[1] & MCI_STATUS_VAL)
5357 mce->status |= MCI_STATUS_OVER;
5358 banks[2] = mce->addr;
5359 banks[3] = mce->misc;
5360 vcpu->arch.mcg_status = mce->mcg_status;
5361 banks[1] = mce->status;
5362 kvm_queue_exception(vcpu, MC_VECTOR);
5363 } else if (!(banks[1] & MCI_STATUS_VAL)
5364 || !(banks[1] & MCI_STATUS_UC)) {
5365 if (banks[1] & MCI_STATUS_VAL)
5366 mce->status |= MCI_STATUS_OVER;
5367 banks[2] = mce->addr;
5368 banks[3] = mce->misc;
5369 banks[1] = mce->status;
5370 } else
5371 banks[1] |= MCI_STATUS_OVER;
5372 return 0;
5373 }
5374
kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)5375 static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
5376 struct kvm_vcpu_events *events)
5377 {
5378 struct kvm_queued_exception *ex;
5379
5380 process_nmi(vcpu);
5381
5382 #ifdef CONFIG_KVM_SMM
5383 if (kvm_check_request(KVM_REQ_SMI, vcpu))
5384 process_smi(vcpu);
5385 #endif
5386
5387 /*
5388 * KVM's ABI only allows for one exception to be migrated. Luckily,
5389 * the only time there can be two queued exceptions is if there's a
5390 * non-exiting _injected_ exception, and a pending exiting exception.
5391 * In that case, ignore the VM-Exiting exception as it's an extension
5392 * of the injected exception.
5393 */
5394 if (vcpu->arch.exception_vmexit.pending &&
5395 !vcpu->arch.exception.pending &&
5396 !vcpu->arch.exception.injected)
5397 ex = &vcpu->arch.exception_vmexit;
5398 else
5399 ex = &vcpu->arch.exception;
5400
5401 /*
5402 * In guest mode, payload delivery should be deferred if the exception
5403 * will be intercepted by L1, e.g. KVM should not modifying CR2 if L1
5404 * intercepts #PF, ditto for DR6 and #DBs. If the per-VM capability,
5405 * KVM_CAP_EXCEPTION_PAYLOAD, is not set, userspace may or may not
5406 * propagate the payload and so it cannot be safely deferred. Deliver
5407 * the payload if the capability hasn't been requested.
5408 */
5409 if (!vcpu->kvm->arch.exception_payload_enabled &&
5410 ex->pending && ex->has_payload)
5411 kvm_deliver_exception_payload(vcpu, ex);
5412
5413 memset(events, 0, sizeof(*events));
5414
5415 /*
5416 * The API doesn't provide the instruction length for software
5417 * exceptions, so don't report them. As long as the guest RIP
5418 * isn't advanced, we should expect to encounter the exception
5419 * again.
5420 */
5421 if (!kvm_exception_is_soft(ex->vector)) {
5422 events->exception.injected = ex->injected;
5423 events->exception.pending = ex->pending;
5424 /*
5425 * For ABI compatibility, deliberately conflate
5426 * pending and injected exceptions when
5427 * KVM_CAP_EXCEPTION_PAYLOAD isn't enabled.
5428 */
5429 if (!vcpu->kvm->arch.exception_payload_enabled)
5430 events->exception.injected |= ex->pending;
5431 }
5432 events->exception.nr = ex->vector;
5433 events->exception.has_error_code = ex->has_error_code;
5434 events->exception.error_code = ex->error_code;
5435 events->exception_has_payload = ex->has_payload;
5436 events->exception_payload = ex->payload;
5437
5438 events->interrupt.injected =
5439 vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft;
5440 events->interrupt.nr = vcpu->arch.interrupt.nr;
5441 events->interrupt.shadow = kvm_x86_call(get_interrupt_shadow)(vcpu);
5442
5443 events->nmi.injected = vcpu->arch.nmi_injected;
5444 events->nmi.pending = kvm_get_nr_pending_nmis(vcpu);
5445 events->nmi.masked = kvm_x86_call(get_nmi_mask)(vcpu);
5446
5447 /* events->sipi_vector is never valid when reporting to user space */
5448
5449 #ifdef CONFIG_KVM_SMM
5450 events->smi.smm = is_smm(vcpu);
5451 events->smi.pending = vcpu->arch.smi_pending;
5452 events->smi.smm_inside_nmi =
5453 !!(vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK);
5454 #endif
5455 events->smi.latched_init = kvm_lapic_latched_init(vcpu);
5456
5457 events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING
5458 | KVM_VCPUEVENT_VALID_SHADOW
5459 | KVM_VCPUEVENT_VALID_SMM);
5460 if (vcpu->kvm->arch.exception_payload_enabled)
5461 events->flags |= KVM_VCPUEVENT_VALID_PAYLOAD;
5462 if (vcpu->kvm->arch.triple_fault_event) {
5463 events->triple_fault.pending = kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5464 events->flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT;
5465 }
5466 }
5467
kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)5468 static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
5469 struct kvm_vcpu_events *events)
5470 {
5471 if (events->flags & ~(KVM_VCPUEVENT_VALID_NMI_PENDING
5472 | KVM_VCPUEVENT_VALID_SIPI_VECTOR
5473 | KVM_VCPUEVENT_VALID_SHADOW
5474 | KVM_VCPUEVENT_VALID_SMM
5475 | KVM_VCPUEVENT_VALID_PAYLOAD
5476 | KVM_VCPUEVENT_VALID_TRIPLE_FAULT))
5477 return -EINVAL;
5478
5479 if (events->flags & KVM_VCPUEVENT_VALID_PAYLOAD) {
5480 if (!vcpu->kvm->arch.exception_payload_enabled)
5481 return -EINVAL;
5482 if (events->exception.pending)
5483 events->exception.injected = 0;
5484 else
5485 events->exception_has_payload = 0;
5486 } else {
5487 events->exception.pending = 0;
5488 events->exception_has_payload = 0;
5489 }
5490
5491 if ((events->exception.injected || events->exception.pending) &&
5492 (events->exception.nr > 31 || events->exception.nr == NMI_VECTOR))
5493 return -EINVAL;
5494
5495 process_nmi(vcpu);
5496
5497 /*
5498 * Flag that userspace is stuffing an exception, the next KVM_RUN will
5499 * morph the exception to a VM-Exit if appropriate. Do this only for
5500 * pending exceptions, already-injected exceptions are not subject to
5501 * intercpetion. Note, userspace that conflates pending and injected
5502 * is hosed, and will incorrectly convert an injected exception into a
5503 * pending exception, which in turn may cause a spurious VM-Exit.
5504 */
5505 vcpu->arch.exception_from_userspace = events->exception.pending;
5506
5507 vcpu->arch.exception_vmexit.pending = false;
5508
5509 vcpu->arch.exception.injected = events->exception.injected;
5510 vcpu->arch.exception.pending = events->exception.pending;
5511 vcpu->arch.exception.vector = events->exception.nr;
5512 vcpu->arch.exception.has_error_code = events->exception.has_error_code;
5513 vcpu->arch.exception.error_code = events->exception.error_code;
5514 vcpu->arch.exception.has_payload = events->exception_has_payload;
5515 vcpu->arch.exception.payload = events->exception_payload;
5516
5517 vcpu->arch.interrupt.injected = events->interrupt.injected;
5518 vcpu->arch.interrupt.nr = events->interrupt.nr;
5519 vcpu->arch.interrupt.soft = events->interrupt.soft;
5520 if (events->flags & KVM_VCPUEVENT_VALID_SHADOW)
5521 kvm_x86_call(set_interrupt_shadow)(vcpu,
5522 events->interrupt.shadow);
5523
5524 vcpu->arch.nmi_injected = events->nmi.injected;
5525 if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING) {
5526 vcpu->arch.nmi_pending = 0;
5527 atomic_set(&vcpu->arch.nmi_queued, events->nmi.pending);
5528 if (events->nmi.pending)
5529 kvm_make_request(KVM_REQ_NMI, vcpu);
5530 }
5531 kvm_x86_call(set_nmi_mask)(vcpu, events->nmi.masked);
5532
5533 if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR &&
5534 lapic_in_kernel(vcpu))
5535 vcpu->arch.apic->sipi_vector = events->sipi_vector;
5536
5537 if (events->flags & KVM_VCPUEVENT_VALID_SMM) {
5538 #ifdef CONFIG_KVM_SMM
5539 if (!!(vcpu->arch.hflags & HF_SMM_MASK) != events->smi.smm) {
5540 kvm_leave_nested(vcpu);
5541 kvm_smm_changed(vcpu, events->smi.smm);
5542 }
5543
5544 vcpu->arch.smi_pending = events->smi.pending;
5545
5546 if (events->smi.smm) {
5547 if (events->smi.smm_inside_nmi)
5548 vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
5549 else
5550 vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
5551 }
5552
5553 #else
5554 if (events->smi.smm || events->smi.pending ||
5555 events->smi.smm_inside_nmi)
5556 return -EINVAL;
5557 #endif
5558
5559 if (lapic_in_kernel(vcpu)) {
5560 if (events->smi.latched_init)
5561 set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
5562 else
5563 clear_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
5564 }
5565 }
5566
5567 if (events->flags & KVM_VCPUEVENT_VALID_TRIPLE_FAULT) {
5568 if (!vcpu->kvm->arch.triple_fault_event)
5569 return -EINVAL;
5570 if (events->triple_fault.pending)
5571 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5572 else
5573 kvm_clear_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5574 }
5575
5576 kvm_make_request(KVM_REQ_EVENT, vcpu);
5577
5578 return 0;
5579 }
5580
kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu * vcpu,struct kvm_debugregs * dbgregs)5581 static int kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu,
5582 struct kvm_debugregs *dbgregs)
5583 {
5584 unsigned int i;
5585
5586 if (vcpu->kvm->arch.has_protected_state &&
5587 vcpu->arch.guest_state_protected)
5588 return -EINVAL;
5589
5590 memset(dbgregs, 0, sizeof(*dbgregs));
5591
5592 BUILD_BUG_ON(ARRAY_SIZE(vcpu->arch.db) != ARRAY_SIZE(dbgregs->db));
5593 for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++)
5594 dbgregs->db[i] = vcpu->arch.db[i];
5595
5596 dbgregs->dr6 = vcpu->arch.dr6;
5597 dbgregs->dr7 = vcpu->arch.dr7;
5598 return 0;
5599 }
5600
kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu * vcpu,struct kvm_debugregs * dbgregs)5601 static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
5602 struct kvm_debugregs *dbgregs)
5603 {
5604 unsigned int i;
5605
5606 if (vcpu->kvm->arch.has_protected_state &&
5607 vcpu->arch.guest_state_protected)
5608 return -EINVAL;
5609
5610 if (dbgregs->flags)
5611 return -EINVAL;
5612
5613 if (!kvm_dr6_valid(dbgregs->dr6))
5614 return -EINVAL;
5615 if (!kvm_dr7_valid(dbgregs->dr7))
5616 return -EINVAL;
5617
5618 for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++)
5619 vcpu->arch.db[i] = dbgregs->db[i];
5620
5621 kvm_update_dr0123(vcpu);
5622 vcpu->arch.dr6 = dbgregs->dr6;
5623 vcpu->arch.dr7 = dbgregs->dr7;
5624 kvm_update_dr7(vcpu);
5625
5626 return 0;
5627 }
5628
5629
kvm_vcpu_ioctl_x86_get_xsave2(struct kvm_vcpu * vcpu,u8 * state,unsigned int size)5630 static int kvm_vcpu_ioctl_x86_get_xsave2(struct kvm_vcpu *vcpu,
5631 u8 *state, unsigned int size)
5632 {
5633 /*
5634 * Only copy state for features that are enabled for the guest. The
5635 * state itself isn't problematic, but setting bits in the header for
5636 * features that are supported in *this* host but not exposed to the
5637 * guest can result in KVM_SET_XSAVE failing when live migrating to a
5638 * compatible host without the features that are NOT exposed to the
5639 * guest.
5640 *
5641 * FP+SSE can always be saved/restored via KVM_{G,S}ET_XSAVE, even if
5642 * XSAVE/XCRO are not exposed to the guest, and even if XSAVE isn't
5643 * supported by the host.
5644 */
5645 u64 supported_xcr0 = vcpu->arch.guest_supported_xcr0 |
5646 XFEATURE_MASK_FPSSE;
5647
5648 if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
5649 return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
5650
5651 fpu_copy_guest_fpstate_to_uabi(&vcpu->arch.guest_fpu, state, size,
5652 supported_xcr0, vcpu->arch.pkru);
5653 return 0;
5654 }
5655
kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu * vcpu,struct kvm_xsave * guest_xsave)5656 static int kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu,
5657 struct kvm_xsave *guest_xsave)
5658 {
5659 return kvm_vcpu_ioctl_x86_get_xsave2(vcpu, (void *)guest_xsave->region,
5660 sizeof(guest_xsave->region));
5661 }
5662
kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu * vcpu,struct kvm_xsave * guest_xsave)5663 static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu,
5664 struct kvm_xsave *guest_xsave)
5665 {
5666 if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
5667 return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
5668
5669 return fpu_copy_uabi_to_guest_fpstate(&vcpu->arch.guest_fpu,
5670 guest_xsave->region,
5671 kvm_caps.supported_xcr0,
5672 &vcpu->arch.pkru);
5673 }
5674
kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu * vcpu,struct kvm_xcrs * guest_xcrs)5675 static int kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu *vcpu,
5676 struct kvm_xcrs *guest_xcrs)
5677 {
5678 if (vcpu->kvm->arch.has_protected_state &&
5679 vcpu->arch.guest_state_protected)
5680 return -EINVAL;
5681
5682 if (!boot_cpu_has(X86_FEATURE_XSAVE)) {
5683 guest_xcrs->nr_xcrs = 0;
5684 return 0;
5685 }
5686
5687 guest_xcrs->nr_xcrs = 1;
5688 guest_xcrs->flags = 0;
5689 guest_xcrs->xcrs[0].xcr = XCR_XFEATURE_ENABLED_MASK;
5690 guest_xcrs->xcrs[0].value = vcpu->arch.xcr0;
5691 return 0;
5692 }
5693
kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu * vcpu,struct kvm_xcrs * guest_xcrs)5694 static int kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu *vcpu,
5695 struct kvm_xcrs *guest_xcrs)
5696 {
5697 int i, r = 0;
5698
5699 if (vcpu->kvm->arch.has_protected_state &&
5700 vcpu->arch.guest_state_protected)
5701 return -EINVAL;
5702
5703 if (!boot_cpu_has(X86_FEATURE_XSAVE))
5704 return -EINVAL;
5705
5706 if (guest_xcrs->nr_xcrs > KVM_MAX_XCRS || guest_xcrs->flags)
5707 return -EINVAL;
5708
5709 for (i = 0; i < guest_xcrs->nr_xcrs; i++)
5710 /* Only support XCR0 currently */
5711 if (guest_xcrs->xcrs[i].xcr == XCR_XFEATURE_ENABLED_MASK) {
5712 r = __kvm_set_xcr(vcpu, XCR_XFEATURE_ENABLED_MASK,
5713 guest_xcrs->xcrs[i].value);
5714 break;
5715 }
5716 if (r)
5717 r = -EINVAL;
5718 return r;
5719 }
5720
5721 /*
5722 * kvm_set_guest_paused() indicates to the guest kernel that it has been
5723 * stopped by the hypervisor. This function will be called from the host only.
5724 * EINVAL is returned when the host attempts to set the flag for a guest that
5725 * does not support pv clocks.
5726 */
kvm_set_guest_paused(struct kvm_vcpu * vcpu)5727 static int kvm_set_guest_paused(struct kvm_vcpu *vcpu)
5728 {
5729 if (!vcpu->arch.pv_time.active)
5730 return -EINVAL;
5731 vcpu->arch.pvclock_set_guest_stopped_request = true;
5732 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
5733 return 0;
5734 }
5735
kvm_arch_tsc_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)5736 static int kvm_arch_tsc_has_attr(struct kvm_vcpu *vcpu,
5737 struct kvm_device_attr *attr)
5738 {
5739 int r;
5740
5741 switch (attr->attr) {
5742 case KVM_VCPU_TSC_OFFSET:
5743 r = 0;
5744 break;
5745 default:
5746 r = -ENXIO;
5747 }
5748
5749 return r;
5750 }
5751
kvm_arch_tsc_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)5752 static int kvm_arch_tsc_get_attr(struct kvm_vcpu *vcpu,
5753 struct kvm_device_attr *attr)
5754 {
5755 u64 __user *uaddr = u64_to_user_ptr(attr->addr);
5756 int r;
5757
5758 switch (attr->attr) {
5759 case KVM_VCPU_TSC_OFFSET:
5760 r = -EFAULT;
5761 if (put_user(vcpu->arch.l1_tsc_offset, uaddr))
5762 break;
5763 r = 0;
5764 break;
5765 default:
5766 r = -ENXIO;
5767 }
5768
5769 return r;
5770 }
5771
kvm_arch_tsc_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)5772 static int kvm_arch_tsc_set_attr(struct kvm_vcpu *vcpu,
5773 struct kvm_device_attr *attr)
5774 {
5775 u64 __user *uaddr = u64_to_user_ptr(attr->addr);
5776 struct kvm *kvm = vcpu->kvm;
5777 int r;
5778
5779 switch (attr->attr) {
5780 case KVM_VCPU_TSC_OFFSET: {
5781 u64 offset, tsc, ns;
5782 unsigned long flags;
5783 bool matched;
5784
5785 r = -EFAULT;
5786 if (get_user(offset, uaddr))
5787 break;
5788
5789 raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
5790
5791 matched = (vcpu->arch.virtual_tsc_khz &&
5792 kvm->arch.last_tsc_khz == vcpu->arch.virtual_tsc_khz &&
5793 kvm->arch.last_tsc_offset == offset);
5794
5795 tsc = kvm_scale_tsc(rdtsc(), vcpu->arch.l1_tsc_scaling_ratio) + offset;
5796 ns = get_kvmclock_base_ns();
5797
5798 __kvm_synchronize_tsc(vcpu, offset, tsc, ns, matched, true);
5799 raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
5800
5801 r = 0;
5802 break;
5803 }
5804 default:
5805 r = -ENXIO;
5806 }
5807
5808 return r;
5809 }
5810
kvm_vcpu_ioctl_device_attr(struct kvm_vcpu * vcpu,unsigned int ioctl,void __user * argp)5811 static int kvm_vcpu_ioctl_device_attr(struct kvm_vcpu *vcpu,
5812 unsigned int ioctl,
5813 void __user *argp)
5814 {
5815 struct kvm_device_attr attr;
5816 int r;
5817
5818 if (copy_from_user(&attr, argp, sizeof(attr)))
5819 return -EFAULT;
5820
5821 if (attr.group != KVM_VCPU_TSC_CTRL)
5822 return -ENXIO;
5823
5824 switch (ioctl) {
5825 case KVM_HAS_DEVICE_ATTR:
5826 r = kvm_arch_tsc_has_attr(vcpu, &attr);
5827 break;
5828 case KVM_GET_DEVICE_ATTR:
5829 r = kvm_arch_tsc_get_attr(vcpu, &attr);
5830 break;
5831 case KVM_SET_DEVICE_ATTR:
5832 r = kvm_arch_tsc_set_attr(vcpu, &attr);
5833 break;
5834 }
5835
5836 return r;
5837 }
5838
kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu * vcpu,struct kvm_enable_cap * cap)5839 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
5840 struct kvm_enable_cap *cap)
5841 {
5842 if (cap->flags)
5843 return -EINVAL;
5844
5845 switch (cap->cap) {
5846 #ifdef CONFIG_KVM_HYPERV
5847 case KVM_CAP_HYPERV_SYNIC2:
5848 if (cap->args[0])
5849 return -EINVAL;
5850 fallthrough;
5851
5852 case KVM_CAP_HYPERV_SYNIC:
5853 if (!irqchip_in_kernel(vcpu->kvm))
5854 return -EINVAL;
5855 return kvm_hv_activate_synic(vcpu, cap->cap ==
5856 KVM_CAP_HYPERV_SYNIC2);
5857 case KVM_CAP_HYPERV_ENLIGHTENED_VMCS:
5858 {
5859 int r;
5860 uint16_t vmcs_version;
5861 void __user *user_ptr;
5862
5863 if (!kvm_x86_ops.nested_ops->enable_evmcs)
5864 return -ENOTTY;
5865 r = kvm_x86_ops.nested_ops->enable_evmcs(vcpu, &vmcs_version);
5866 if (!r) {
5867 user_ptr = (void __user *)(uintptr_t)cap->args[0];
5868 if (copy_to_user(user_ptr, &vmcs_version,
5869 sizeof(vmcs_version)))
5870 r = -EFAULT;
5871 }
5872 return r;
5873 }
5874 case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
5875 if (!kvm_x86_ops.enable_l2_tlb_flush)
5876 return -ENOTTY;
5877
5878 return kvm_x86_call(enable_l2_tlb_flush)(vcpu);
5879
5880 case KVM_CAP_HYPERV_ENFORCE_CPUID:
5881 return kvm_hv_set_enforce_cpuid(vcpu, cap->args[0]);
5882 #endif
5883
5884 case KVM_CAP_ENFORCE_PV_FEATURE_CPUID:
5885 vcpu->arch.pv_cpuid.enforce = cap->args[0];
5886 return 0;
5887 default:
5888 return -EINVAL;
5889 }
5890 }
5891
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)5892 long kvm_arch_vcpu_ioctl(struct file *filp,
5893 unsigned int ioctl, unsigned long arg)
5894 {
5895 struct kvm_vcpu *vcpu = filp->private_data;
5896 void __user *argp = (void __user *)arg;
5897 int r;
5898 union {
5899 struct kvm_sregs2 *sregs2;
5900 struct kvm_lapic_state *lapic;
5901 struct kvm_xsave *xsave;
5902 struct kvm_xcrs *xcrs;
5903 void *buffer;
5904 } u;
5905
5906 vcpu_load(vcpu);
5907
5908 u.buffer = NULL;
5909 switch (ioctl) {
5910 case KVM_GET_LAPIC: {
5911 r = -EINVAL;
5912 if (!lapic_in_kernel(vcpu))
5913 goto out;
5914 u.lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
5915
5916 r = -ENOMEM;
5917 if (!u.lapic)
5918 goto out;
5919 r = kvm_vcpu_ioctl_get_lapic(vcpu, u.lapic);
5920 if (r)
5921 goto out;
5922 r = -EFAULT;
5923 if (copy_to_user(argp, u.lapic, sizeof(struct kvm_lapic_state)))
5924 goto out;
5925 r = 0;
5926 break;
5927 }
5928 case KVM_SET_LAPIC: {
5929 r = -EINVAL;
5930 if (!lapic_in_kernel(vcpu))
5931 goto out;
5932 u.lapic = memdup_user(argp, sizeof(*u.lapic));
5933 if (IS_ERR(u.lapic)) {
5934 r = PTR_ERR(u.lapic);
5935 goto out_nofree;
5936 }
5937
5938 r = kvm_vcpu_ioctl_set_lapic(vcpu, u.lapic);
5939 break;
5940 }
5941 case KVM_INTERRUPT: {
5942 struct kvm_interrupt irq;
5943
5944 r = -EFAULT;
5945 if (copy_from_user(&irq, argp, sizeof(irq)))
5946 goto out;
5947 r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
5948 break;
5949 }
5950 case KVM_NMI: {
5951 r = kvm_vcpu_ioctl_nmi(vcpu);
5952 break;
5953 }
5954 case KVM_SMI: {
5955 r = kvm_inject_smi(vcpu);
5956 break;
5957 }
5958 case KVM_SET_CPUID: {
5959 struct kvm_cpuid __user *cpuid_arg = argp;
5960 struct kvm_cpuid cpuid;
5961
5962 r = -EFAULT;
5963 if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
5964 goto out;
5965 r = kvm_vcpu_ioctl_set_cpuid(vcpu, &cpuid, cpuid_arg->entries);
5966 break;
5967 }
5968 case KVM_SET_CPUID2: {
5969 struct kvm_cpuid2 __user *cpuid_arg = argp;
5970 struct kvm_cpuid2 cpuid;
5971
5972 r = -EFAULT;
5973 if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
5974 goto out;
5975 r = kvm_vcpu_ioctl_set_cpuid2(vcpu, &cpuid,
5976 cpuid_arg->entries);
5977 break;
5978 }
5979 case KVM_GET_CPUID2: {
5980 struct kvm_cpuid2 __user *cpuid_arg = argp;
5981 struct kvm_cpuid2 cpuid;
5982
5983 r = -EFAULT;
5984 if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
5985 goto out;
5986 r = kvm_vcpu_ioctl_get_cpuid2(vcpu, &cpuid,
5987 cpuid_arg->entries);
5988 if (r)
5989 goto out;
5990 r = -EFAULT;
5991 if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
5992 goto out;
5993 r = 0;
5994 break;
5995 }
5996 case KVM_GET_MSRS: {
5997 int idx = srcu_read_lock(&vcpu->kvm->srcu);
5998 r = msr_io(vcpu, argp, do_get_msr, 1);
5999 srcu_read_unlock(&vcpu->kvm->srcu, idx);
6000 break;
6001 }
6002 case KVM_SET_MSRS: {
6003 int idx = srcu_read_lock(&vcpu->kvm->srcu);
6004 r = msr_io(vcpu, argp, do_set_msr, 0);
6005 srcu_read_unlock(&vcpu->kvm->srcu, idx);
6006 break;
6007 }
6008 case KVM_TPR_ACCESS_REPORTING: {
6009 struct kvm_tpr_access_ctl tac;
6010
6011 r = -EFAULT;
6012 if (copy_from_user(&tac, argp, sizeof(tac)))
6013 goto out;
6014 r = vcpu_ioctl_tpr_access_reporting(vcpu, &tac);
6015 if (r)
6016 goto out;
6017 r = -EFAULT;
6018 if (copy_to_user(argp, &tac, sizeof(tac)))
6019 goto out;
6020 r = 0;
6021 break;
6022 };
6023 case KVM_SET_VAPIC_ADDR: {
6024 struct kvm_vapic_addr va;
6025 int idx;
6026
6027 r = -EINVAL;
6028 if (!lapic_in_kernel(vcpu))
6029 goto out;
6030 r = -EFAULT;
6031 if (copy_from_user(&va, argp, sizeof(va)))
6032 goto out;
6033 idx = srcu_read_lock(&vcpu->kvm->srcu);
6034 r = kvm_lapic_set_vapic_addr(vcpu, va.vapic_addr);
6035 srcu_read_unlock(&vcpu->kvm->srcu, idx);
6036 break;
6037 }
6038 case KVM_X86_SETUP_MCE: {
6039 u64 mcg_cap;
6040
6041 r = -EFAULT;
6042 if (copy_from_user(&mcg_cap, argp, sizeof(mcg_cap)))
6043 goto out;
6044 r = kvm_vcpu_ioctl_x86_setup_mce(vcpu, mcg_cap);
6045 break;
6046 }
6047 case KVM_X86_SET_MCE: {
6048 struct kvm_x86_mce mce;
6049
6050 r = -EFAULT;
6051 if (copy_from_user(&mce, argp, sizeof(mce)))
6052 goto out;
6053 r = kvm_vcpu_ioctl_x86_set_mce(vcpu, &mce);
6054 break;
6055 }
6056 case KVM_GET_VCPU_EVENTS: {
6057 struct kvm_vcpu_events events;
6058
6059 kvm_vcpu_ioctl_x86_get_vcpu_events(vcpu, &events);
6060
6061 r = -EFAULT;
6062 if (copy_to_user(argp, &events, sizeof(struct kvm_vcpu_events)))
6063 break;
6064 r = 0;
6065 break;
6066 }
6067 case KVM_SET_VCPU_EVENTS: {
6068 struct kvm_vcpu_events events;
6069
6070 r = -EFAULT;
6071 if (copy_from_user(&events, argp, sizeof(struct kvm_vcpu_events)))
6072 break;
6073
6074 kvm_vcpu_srcu_read_lock(vcpu);
6075 r = kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events);
6076 kvm_vcpu_srcu_read_unlock(vcpu);
6077 break;
6078 }
6079 case KVM_GET_DEBUGREGS: {
6080 struct kvm_debugregs dbgregs;
6081
6082 r = kvm_vcpu_ioctl_x86_get_debugregs(vcpu, &dbgregs);
6083 if (r < 0)
6084 break;
6085
6086 r = -EFAULT;
6087 if (copy_to_user(argp, &dbgregs,
6088 sizeof(struct kvm_debugregs)))
6089 break;
6090 r = 0;
6091 break;
6092 }
6093 case KVM_SET_DEBUGREGS: {
6094 struct kvm_debugregs dbgregs;
6095
6096 r = -EFAULT;
6097 if (copy_from_user(&dbgregs, argp,
6098 sizeof(struct kvm_debugregs)))
6099 break;
6100
6101 r = kvm_vcpu_ioctl_x86_set_debugregs(vcpu, &dbgregs);
6102 break;
6103 }
6104 case KVM_GET_XSAVE: {
6105 r = -EINVAL;
6106 if (vcpu->arch.guest_fpu.uabi_size > sizeof(struct kvm_xsave))
6107 break;
6108
6109 u.xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL);
6110 r = -ENOMEM;
6111 if (!u.xsave)
6112 break;
6113
6114 r = kvm_vcpu_ioctl_x86_get_xsave(vcpu, u.xsave);
6115 if (r < 0)
6116 break;
6117
6118 r = -EFAULT;
6119 if (copy_to_user(argp, u.xsave, sizeof(struct kvm_xsave)))
6120 break;
6121 r = 0;
6122 break;
6123 }
6124 case KVM_SET_XSAVE: {
6125 int size = vcpu->arch.guest_fpu.uabi_size;
6126
6127 u.xsave = memdup_user(argp, size);
6128 if (IS_ERR(u.xsave)) {
6129 r = PTR_ERR(u.xsave);
6130 goto out_nofree;
6131 }
6132
6133 r = kvm_vcpu_ioctl_x86_set_xsave(vcpu, u.xsave);
6134 break;
6135 }
6136
6137 case KVM_GET_XSAVE2: {
6138 int size = vcpu->arch.guest_fpu.uabi_size;
6139
6140 u.xsave = kzalloc(size, GFP_KERNEL);
6141 r = -ENOMEM;
6142 if (!u.xsave)
6143 break;
6144
6145 r = kvm_vcpu_ioctl_x86_get_xsave2(vcpu, u.buffer, size);
6146 if (r < 0)
6147 break;
6148
6149 r = -EFAULT;
6150 if (copy_to_user(argp, u.xsave, size))
6151 break;
6152
6153 r = 0;
6154 break;
6155 }
6156
6157 case KVM_GET_XCRS: {
6158 u.xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL);
6159 r = -ENOMEM;
6160 if (!u.xcrs)
6161 break;
6162
6163 r = kvm_vcpu_ioctl_x86_get_xcrs(vcpu, u.xcrs);
6164 if (r < 0)
6165 break;
6166
6167 r = -EFAULT;
6168 if (copy_to_user(argp, u.xcrs,
6169 sizeof(struct kvm_xcrs)))
6170 break;
6171 r = 0;
6172 break;
6173 }
6174 case KVM_SET_XCRS: {
6175 u.xcrs = memdup_user(argp, sizeof(*u.xcrs));
6176 if (IS_ERR(u.xcrs)) {
6177 r = PTR_ERR(u.xcrs);
6178 goto out_nofree;
6179 }
6180
6181 r = kvm_vcpu_ioctl_x86_set_xcrs(vcpu, u.xcrs);
6182 break;
6183 }
6184 case KVM_SET_TSC_KHZ: {
6185 u32 user_tsc_khz;
6186
6187 r = -EINVAL;
6188
6189 if (vcpu->arch.guest_tsc_protected)
6190 goto out;
6191
6192 user_tsc_khz = (u32)arg;
6193
6194 if (kvm_caps.has_tsc_control &&
6195 user_tsc_khz >= kvm_caps.max_guest_tsc_khz)
6196 goto out;
6197
6198 if (user_tsc_khz == 0)
6199 user_tsc_khz = tsc_khz;
6200
6201 if (!kvm_set_tsc_khz(vcpu, user_tsc_khz))
6202 r = 0;
6203
6204 goto out;
6205 }
6206 case KVM_GET_TSC_KHZ: {
6207 r = vcpu->arch.virtual_tsc_khz;
6208 goto out;
6209 }
6210 case KVM_KVMCLOCK_CTRL: {
6211 r = kvm_set_guest_paused(vcpu);
6212 goto out;
6213 }
6214 case KVM_ENABLE_CAP: {
6215 struct kvm_enable_cap cap;
6216
6217 r = -EFAULT;
6218 if (copy_from_user(&cap, argp, sizeof(cap)))
6219 goto out;
6220 r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
6221 break;
6222 }
6223 case KVM_GET_NESTED_STATE: {
6224 struct kvm_nested_state __user *user_kvm_nested_state = argp;
6225 u32 user_data_size;
6226
6227 r = -EINVAL;
6228 if (!kvm_x86_ops.nested_ops->get_state)
6229 break;
6230
6231 BUILD_BUG_ON(sizeof(user_data_size) != sizeof(user_kvm_nested_state->size));
6232 r = -EFAULT;
6233 if (get_user(user_data_size, &user_kvm_nested_state->size))
6234 break;
6235
6236 r = kvm_x86_ops.nested_ops->get_state(vcpu, user_kvm_nested_state,
6237 user_data_size);
6238 if (r < 0)
6239 break;
6240
6241 if (r > user_data_size) {
6242 if (put_user(r, &user_kvm_nested_state->size))
6243 r = -EFAULT;
6244 else
6245 r = -E2BIG;
6246 break;
6247 }
6248
6249 r = 0;
6250 break;
6251 }
6252 case KVM_SET_NESTED_STATE: {
6253 struct kvm_nested_state __user *user_kvm_nested_state = argp;
6254 struct kvm_nested_state kvm_state;
6255 int idx;
6256
6257 r = -EINVAL;
6258 if (!kvm_x86_ops.nested_ops->set_state)
6259 break;
6260
6261 r = -EFAULT;
6262 if (copy_from_user(&kvm_state, user_kvm_nested_state, sizeof(kvm_state)))
6263 break;
6264
6265 r = -EINVAL;
6266 if (kvm_state.size < sizeof(kvm_state))
6267 break;
6268
6269 if (kvm_state.flags &
6270 ~(KVM_STATE_NESTED_RUN_PENDING | KVM_STATE_NESTED_GUEST_MODE
6271 | KVM_STATE_NESTED_EVMCS | KVM_STATE_NESTED_MTF_PENDING
6272 | KVM_STATE_NESTED_GIF_SET))
6273 break;
6274
6275 /* nested_run_pending implies guest_mode. */
6276 if ((kvm_state.flags & KVM_STATE_NESTED_RUN_PENDING)
6277 && !(kvm_state.flags & KVM_STATE_NESTED_GUEST_MODE))
6278 break;
6279
6280 idx = srcu_read_lock(&vcpu->kvm->srcu);
6281 r = kvm_x86_ops.nested_ops->set_state(vcpu, user_kvm_nested_state, &kvm_state);
6282 srcu_read_unlock(&vcpu->kvm->srcu, idx);
6283 break;
6284 }
6285 #ifdef CONFIG_KVM_HYPERV
6286 case KVM_GET_SUPPORTED_HV_CPUID:
6287 r = kvm_ioctl_get_supported_hv_cpuid(vcpu, argp);
6288 break;
6289 #endif
6290 #ifdef CONFIG_KVM_XEN
6291 case KVM_XEN_VCPU_GET_ATTR: {
6292 struct kvm_xen_vcpu_attr xva;
6293
6294 r = -EFAULT;
6295 if (copy_from_user(&xva, argp, sizeof(xva)))
6296 goto out;
6297 r = kvm_xen_vcpu_get_attr(vcpu, &xva);
6298 if (!r && copy_to_user(argp, &xva, sizeof(xva)))
6299 r = -EFAULT;
6300 break;
6301 }
6302 case KVM_XEN_VCPU_SET_ATTR: {
6303 struct kvm_xen_vcpu_attr xva;
6304
6305 r = -EFAULT;
6306 if (copy_from_user(&xva, argp, sizeof(xva)))
6307 goto out;
6308 r = kvm_xen_vcpu_set_attr(vcpu, &xva);
6309 break;
6310 }
6311 #endif
6312 case KVM_GET_SREGS2: {
6313 r = -EINVAL;
6314 if (vcpu->kvm->arch.has_protected_state &&
6315 vcpu->arch.guest_state_protected)
6316 goto out;
6317
6318 u.sregs2 = kzalloc(sizeof(struct kvm_sregs2), GFP_KERNEL);
6319 r = -ENOMEM;
6320 if (!u.sregs2)
6321 goto out;
6322 __get_sregs2(vcpu, u.sregs2);
6323 r = -EFAULT;
6324 if (copy_to_user(argp, u.sregs2, sizeof(struct kvm_sregs2)))
6325 goto out;
6326 r = 0;
6327 break;
6328 }
6329 case KVM_SET_SREGS2: {
6330 r = -EINVAL;
6331 if (vcpu->kvm->arch.has_protected_state &&
6332 vcpu->arch.guest_state_protected)
6333 goto out;
6334
6335 u.sregs2 = memdup_user(argp, sizeof(struct kvm_sregs2));
6336 if (IS_ERR(u.sregs2)) {
6337 r = PTR_ERR(u.sregs2);
6338 u.sregs2 = NULL;
6339 goto out;
6340 }
6341 r = __set_sregs2(vcpu, u.sregs2);
6342 break;
6343 }
6344 case KVM_HAS_DEVICE_ATTR:
6345 case KVM_GET_DEVICE_ATTR:
6346 case KVM_SET_DEVICE_ATTR:
6347 r = kvm_vcpu_ioctl_device_attr(vcpu, ioctl, argp);
6348 break;
6349 case KVM_MEMORY_ENCRYPT_OP:
6350 r = -ENOTTY;
6351 if (!kvm_x86_ops.vcpu_mem_enc_ioctl)
6352 goto out;
6353 r = kvm_x86_ops.vcpu_mem_enc_ioctl(vcpu, argp);
6354 break;
6355 default:
6356 r = -EINVAL;
6357 }
6358 out:
6359 kfree(u.buffer);
6360 out_nofree:
6361 vcpu_put(vcpu);
6362 return r;
6363 }
6364
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)6365 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
6366 {
6367 return VM_FAULT_SIGBUS;
6368 }
6369
kvm_vm_ioctl_set_tss_addr(struct kvm * kvm,unsigned long addr)6370 static int kvm_vm_ioctl_set_tss_addr(struct kvm *kvm, unsigned long addr)
6371 {
6372 int ret;
6373
6374 if (addr > (unsigned int)(-3 * PAGE_SIZE))
6375 return -EINVAL;
6376 ret = kvm_x86_call(set_tss_addr)(kvm, addr);
6377 return ret;
6378 }
6379
kvm_vm_ioctl_set_identity_map_addr(struct kvm * kvm,u64 ident_addr)6380 static int kvm_vm_ioctl_set_identity_map_addr(struct kvm *kvm,
6381 u64 ident_addr)
6382 {
6383 return kvm_x86_call(set_identity_map_addr)(kvm, ident_addr);
6384 }
6385
kvm_vm_ioctl_set_nr_mmu_pages(struct kvm * kvm,unsigned long kvm_nr_mmu_pages)6386 static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm,
6387 unsigned long kvm_nr_mmu_pages)
6388 {
6389 if (kvm_nr_mmu_pages < KVM_MIN_ALLOC_MMU_PAGES)
6390 return -EINVAL;
6391
6392 mutex_lock(&kvm->slots_lock);
6393
6394 kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages);
6395 kvm->arch.n_requested_mmu_pages = kvm_nr_mmu_pages;
6396
6397 mutex_unlock(&kvm->slots_lock);
6398 return 0;
6399 }
6400
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)6401 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
6402 {
6403
6404 /*
6405 * Flush all CPUs' dirty log buffers to the dirty_bitmap. Called
6406 * before reporting dirty_bitmap to userspace. KVM flushes the buffers
6407 * on all VM-Exits, thus we only need to kick running vCPUs to force a
6408 * VM-Exit.
6409 */
6410 struct kvm_vcpu *vcpu;
6411 unsigned long i;
6412
6413 if (!kvm->arch.cpu_dirty_log_size)
6414 return;
6415
6416 kvm_for_each_vcpu(i, vcpu, kvm)
6417 kvm_vcpu_kick(vcpu);
6418 }
6419
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)6420 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
6421 struct kvm_enable_cap *cap)
6422 {
6423 int r;
6424
6425 if (cap->flags)
6426 return -EINVAL;
6427
6428 switch (cap->cap) {
6429 case KVM_CAP_DISABLE_QUIRKS2:
6430 r = -EINVAL;
6431 if (cap->args[0] & ~kvm_caps.supported_quirks)
6432 break;
6433 fallthrough;
6434 case KVM_CAP_DISABLE_QUIRKS:
6435 kvm->arch.disabled_quirks |= cap->args[0] & kvm_caps.supported_quirks;
6436 r = 0;
6437 break;
6438 case KVM_CAP_SPLIT_IRQCHIP: {
6439 mutex_lock(&kvm->lock);
6440 r = -EINVAL;
6441 if (cap->args[0] > MAX_NR_RESERVED_IOAPIC_PINS)
6442 goto split_irqchip_unlock;
6443 r = -EEXIST;
6444 if (irqchip_in_kernel(kvm))
6445 goto split_irqchip_unlock;
6446 if (kvm->created_vcpus)
6447 goto split_irqchip_unlock;
6448 /* Pairs with irqchip_in_kernel. */
6449 smp_wmb();
6450 kvm->arch.irqchip_mode = KVM_IRQCHIP_SPLIT;
6451 kvm->arch.nr_reserved_ioapic_pins = cap->args[0];
6452 kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_ABSENT);
6453 r = 0;
6454 split_irqchip_unlock:
6455 mutex_unlock(&kvm->lock);
6456 break;
6457 }
6458 case KVM_CAP_X2APIC_API:
6459 r = -EINVAL;
6460 if (cap->args[0] & ~KVM_X2APIC_API_VALID_FLAGS)
6461 break;
6462
6463 if (cap->args[0] & KVM_X2APIC_API_USE_32BIT_IDS)
6464 kvm->arch.x2apic_format = true;
6465 if (cap->args[0] & KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK)
6466 kvm->arch.x2apic_broadcast_quirk_disabled = true;
6467
6468 r = 0;
6469 break;
6470 case KVM_CAP_X86_DISABLE_EXITS:
6471 r = -EINVAL;
6472 if (cap->args[0] & ~kvm_get_allowed_disable_exits())
6473 break;
6474
6475 mutex_lock(&kvm->lock);
6476 if (kvm->created_vcpus)
6477 goto disable_exits_unlock;
6478
6479 #define SMT_RSB_MSG "This processor is affected by the Cross-Thread Return Predictions vulnerability. " \
6480 "KVM_CAP_X86_DISABLE_EXITS should only be used with SMT disabled or trusted guests."
6481
6482 if (!mitigate_smt_rsb && boot_cpu_has_bug(X86_BUG_SMT_RSB) &&
6483 cpu_smt_possible() &&
6484 (cap->args[0] & ~(KVM_X86_DISABLE_EXITS_PAUSE |
6485 KVM_X86_DISABLE_EXITS_APERFMPERF)))
6486 pr_warn_once(SMT_RSB_MSG);
6487
6488 kvm_disable_exits(kvm, cap->args[0]);
6489 r = 0;
6490 disable_exits_unlock:
6491 mutex_unlock(&kvm->lock);
6492 break;
6493 case KVM_CAP_MSR_PLATFORM_INFO:
6494 kvm->arch.guest_can_read_msr_platform_info = cap->args[0];
6495 r = 0;
6496 break;
6497 case KVM_CAP_EXCEPTION_PAYLOAD:
6498 kvm->arch.exception_payload_enabled = cap->args[0];
6499 r = 0;
6500 break;
6501 case KVM_CAP_X86_TRIPLE_FAULT_EVENT:
6502 kvm->arch.triple_fault_event = cap->args[0];
6503 r = 0;
6504 break;
6505 case KVM_CAP_X86_USER_SPACE_MSR:
6506 r = -EINVAL;
6507 if (cap->args[0] & ~KVM_MSR_EXIT_REASON_VALID_MASK)
6508 break;
6509 kvm->arch.user_space_msr_mask = cap->args[0];
6510 r = 0;
6511 break;
6512 case KVM_CAP_X86_BUS_LOCK_EXIT:
6513 r = -EINVAL;
6514 if (cap->args[0] & ~KVM_BUS_LOCK_DETECTION_VALID_MODE)
6515 break;
6516
6517 if ((cap->args[0] & KVM_BUS_LOCK_DETECTION_OFF) &&
6518 (cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT))
6519 break;
6520
6521 if (kvm_caps.has_bus_lock_exit &&
6522 cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT)
6523 kvm->arch.bus_lock_detection_enabled = true;
6524 r = 0;
6525 break;
6526 #ifdef CONFIG_X86_SGX_KVM
6527 case KVM_CAP_SGX_ATTRIBUTE: {
6528 unsigned long allowed_attributes = 0;
6529
6530 r = sgx_set_attribute(&allowed_attributes, cap->args[0]);
6531 if (r)
6532 break;
6533
6534 /* KVM only supports the PROVISIONKEY privileged attribute. */
6535 if ((allowed_attributes & SGX_ATTR_PROVISIONKEY) &&
6536 !(allowed_attributes & ~SGX_ATTR_PROVISIONKEY))
6537 kvm->arch.sgx_provisioning_allowed = true;
6538 else
6539 r = -EINVAL;
6540 break;
6541 }
6542 #endif
6543 case KVM_CAP_VM_COPY_ENC_CONTEXT_FROM:
6544 r = -EINVAL;
6545 if (!kvm_x86_ops.vm_copy_enc_context_from)
6546 break;
6547
6548 r = kvm_x86_call(vm_copy_enc_context_from)(kvm, cap->args[0]);
6549 break;
6550 case KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM:
6551 r = -EINVAL;
6552 if (!kvm_x86_ops.vm_move_enc_context_from)
6553 break;
6554
6555 r = kvm_x86_call(vm_move_enc_context_from)(kvm, cap->args[0]);
6556 break;
6557 case KVM_CAP_EXIT_HYPERCALL:
6558 if (cap->args[0] & ~KVM_EXIT_HYPERCALL_VALID_MASK) {
6559 r = -EINVAL;
6560 break;
6561 }
6562 kvm->arch.hypercall_exit_enabled = cap->args[0];
6563 r = 0;
6564 break;
6565 case KVM_CAP_EXIT_ON_EMULATION_FAILURE:
6566 r = -EINVAL;
6567 if (cap->args[0] & ~1)
6568 break;
6569 kvm->arch.exit_on_emulation_error = cap->args[0];
6570 r = 0;
6571 break;
6572 case KVM_CAP_PMU_CAPABILITY:
6573 r = -EINVAL;
6574 if (!enable_pmu || (cap->args[0] & ~KVM_CAP_PMU_VALID_MASK))
6575 break;
6576
6577 mutex_lock(&kvm->lock);
6578 if (!kvm->created_vcpus) {
6579 kvm->arch.enable_pmu = !(cap->args[0] & KVM_PMU_CAP_DISABLE);
6580 r = 0;
6581 }
6582 mutex_unlock(&kvm->lock);
6583 break;
6584 case KVM_CAP_MAX_VCPU_ID:
6585 r = -EINVAL;
6586 if (cap->args[0] > KVM_MAX_VCPU_IDS)
6587 break;
6588
6589 mutex_lock(&kvm->lock);
6590 if (kvm->arch.bsp_vcpu_id > cap->args[0]) {
6591 ;
6592 } else if (kvm->arch.max_vcpu_ids == cap->args[0]) {
6593 r = 0;
6594 } else if (!kvm->arch.max_vcpu_ids) {
6595 kvm->arch.max_vcpu_ids = cap->args[0];
6596 r = 0;
6597 }
6598 mutex_unlock(&kvm->lock);
6599 break;
6600 case KVM_CAP_X86_NOTIFY_VMEXIT:
6601 r = -EINVAL;
6602 if ((u32)cap->args[0] & ~KVM_X86_NOTIFY_VMEXIT_VALID_BITS)
6603 break;
6604 if (!kvm_caps.has_notify_vmexit)
6605 break;
6606 if (!((u32)cap->args[0] & KVM_X86_NOTIFY_VMEXIT_ENABLED))
6607 break;
6608 mutex_lock(&kvm->lock);
6609 if (!kvm->created_vcpus) {
6610 kvm->arch.notify_window = cap->args[0] >> 32;
6611 kvm->arch.notify_vmexit_flags = (u32)cap->args[0];
6612 r = 0;
6613 }
6614 mutex_unlock(&kvm->lock);
6615 break;
6616 case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES:
6617 r = -EINVAL;
6618
6619 /*
6620 * Since the risk of disabling NX hugepages is a guest crashing
6621 * the system, ensure the userspace process has permission to
6622 * reboot the system.
6623 *
6624 * Note that unlike the reboot() syscall, the process must have
6625 * this capability in the root namespace because exposing
6626 * /dev/kvm into a container does not limit the scope of the
6627 * iTLB multihit bug to that container. In other words,
6628 * this must use capable(), not ns_capable().
6629 */
6630 if (!capable(CAP_SYS_BOOT)) {
6631 r = -EPERM;
6632 break;
6633 }
6634
6635 if (cap->args[0])
6636 break;
6637
6638 mutex_lock(&kvm->lock);
6639 if (!kvm->created_vcpus) {
6640 kvm->arch.disable_nx_huge_pages = true;
6641 r = 0;
6642 }
6643 mutex_unlock(&kvm->lock);
6644 break;
6645 case KVM_CAP_X86_APIC_BUS_CYCLES_NS: {
6646 u64 bus_cycle_ns = cap->args[0];
6647 u64 unused;
6648
6649 /*
6650 * Guard against overflow in tmict_to_ns(). 128 is the highest
6651 * divide value that can be programmed in APIC_TDCR.
6652 */
6653 r = -EINVAL;
6654 if (!bus_cycle_ns ||
6655 check_mul_overflow((u64)U32_MAX * 128, bus_cycle_ns, &unused))
6656 break;
6657
6658 r = 0;
6659 mutex_lock(&kvm->lock);
6660 if (!irqchip_in_kernel(kvm))
6661 r = -ENXIO;
6662 else if (kvm->created_vcpus)
6663 r = -EINVAL;
6664 else
6665 kvm->arch.apic_bus_cycle_ns = bus_cycle_ns;
6666 mutex_unlock(&kvm->lock);
6667 break;
6668 }
6669 default:
6670 r = -EINVAL;
6671 break;
6672 }
6673 return r;
6674 }
6675
kvm_alloc_msr_filter(bool default_allow)6676 static struct kvm_x86_msr_filter *kvm_alloc_msr_filter(bool default_allow)
6677 {
6678 struct kvm_x86_msr_filter *msr_filter;
6679
6680 msr_filter = kzalloc(sizeof(*msr_filter), GFP_KERNEL_ACCOUNT);
6681 if (!msr_filter)
6682 return NULL;
6683
6684 msr_filter->default_allow = default_allow;
6685 return msr_filter;
6686 }
6687
kvm_free_msr_filter(struct kvm_x86_msr_filter * msr_filter)6688 static void kvm_free_msr_filter(struct kvm_x86_msr_filter *msr_filter)
6689 {
6690 u32 i;
6691
6692 if (!msr_filter)
6693 return;
6694
6695 for (i = 0; i < msr_filter->count; i++)
6696 kfree(msr_filter->ranges[i].bitmap);
6697
6698 kfree(msr_filter);
6699 }
6700
kvm_add_msr_filter(struct kvm_x86_msr_filter * msr_filter,struct kvm_msr_filter_range * user_range)6701 static int kvm_add_msr_filter(struct kvm_x86_msr_filter *msr_filter,
6702 struct kvm_msr_filter_range *user_range)
6703 {
6704 unsigned long *bitmap;
6705 size_t bitmap_size;
6706
6707 if (!user_range->nmsrs)
6708 return 0;
6709
6710 if (user_range->flags & ~KVM_MSR_FILTER_RANGE_VALID_MASK)
6711 return -EINVAL;
6712
6713 if (!user_range->flags)
6714 return -EINVAL;
6715
6716 bitmap_size = BITS_TO_LONGS(user_range->nmsrs) * sizeof(long);
6717 if (!bitmap_size || bitmap_size > KVM_MSR_FILTER_MAX_BITMAP_SIZE)
6718 return -EINVAL;
6719
6720 bitmap = memdup_user((__user u8*)user_range->bitmap, bitmap_size);
6721 if (IS_ERR(bitmap))
6722 return PTR_ERR(bitmap);
6723
6724 msr_filter->ranges[msr_filter->count] = (struct msr_bitmap_range) {
6725 .flags = user_range->flags,
6726 .base = user_range->base,
6727 .nmsrs = user_range->nmsrs,
6728 .bitmap = bitmap,
6729 };
6730
6731 msr_filter->count++;
6732 return 0;
6733 }
6734
kvm_vm_ioctl_set_msr_filter(struct kvm * kvm,struct kvm_msr_filter * filter)6735 static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm,
6736 struct kvm_msr_filter *filter)
6737 {
6738 struct kvm_x86_msr_filter *new_filter, *old_filter;
6739 bool default_allow;
6740 bool empty = true;
6741 int r;
6742 u32 i;
6743
6744 if (filter->flags & ~KVM_MSR_FILTER_VALID_MASK)
6745 return -EINVAL;
6746
6747 for (i = 0; i < ARRAY_SIZE(filter->ranges); i++)
6748 empty &= !filter->ranges[i].nmsrs;
6749
6750 default_allow = !(filter->flags & KVM_MSR_FILTER_DEFAULT_DENY);
6751 if (empty && !default_allow)
6752 return -EINVAL;
6753
6754 new_filter = kvm_alloc_msr_filter(default_allow);
6755 if (!new_filter)
6756 return -ENOMEM;
6757
6758 for (i = 0; i < ARRAY_SIZE(filter->ranges); i++) {
6759 r = kvm_add_msr_filter(new_filter, &filter->ranges[i]);
6760 if (r) {
6761 kvm_free_msr_filter(new_filter);
6762 return r;
6763 }
6764 }
6765
6766 mutex_lock(&kvm->lock);
6767 old_filter = rcu_replace_pointer(kvm->arch.msr_filter, new_filter,
6768 mutex_is_locked(&kvm->lock));
6769 mutex_unlock(&kvm->lock);
6770 synchronize_srcu(&kvm->srcu);
6771
6772 kvm_free_msr_filter(old_filter);
6773
6774 kvm_make_all_cpus_request(kvm, KVM_REQ_MSR_FILTER_CHANGED);
6775
6776 return 0;
6777 }
6778
6779 #ifdef CONFIG_KVM_COMPAT
6780 /* for KVM_X86_SET_MSR_FILTER */
6781 struct kvm_msr_filter_range_compat {
6782 __u32 flags;
6783 __u32 nmsrs;
6784 __u32 base;
6785 __u32 bitmap;
6786 };
6787
6788 struct kvm_msr_filter_compat {
6789 __u32 flags;
6790 struct kvm_msr_filter_range_compat ranges[KVM_MSR_FILTER_MAX_RANGES];
6791 };
6792
6793 #define KVM_X86_SET_MSR_FILTER_COMPAT _IOW(KVMIO, 0xc6, struct kvm_msr_filter_compat)
6794
kvm_arch_vm_compat_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)6795 long kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl,
6796 unsigned long arg)
6797 {
6798 void __user *argp = (void __user *)arg;
6799 struct kvm *kvm = filp->private_data;
6800 long r = -ENOTTY;
6801
6802 switch (ioctl) {
6803 case KVM_X86_SET_MSR_FILTER_COMPAT: {
6804 struct kvm_msr_filter __user *user_msr_filter = argp;
6805 struct kvm_msr_filter_compat filter_compat;
6806 struct kvm_msr_filter filter;
6807 int i;
6808
6809 if (copy_from_user(&filter_compat, user_msr_filter,
6810 sizeof(filter_compat)))
6811 return -EFAULT;
6812
6813 filter.flags = filter_compat.flags;
6814 for (i = 0; i < ARRAY_SIZE(filter.ranges); i++) {
6815 struct kvm_msr_filter_range_compat *cr;
6816
6817 cr = &filter_compat.ranges[i];
6818 filter.ranges[i] = (struct kvm_msr_filter_range) {
6819 .flags = cr->flags,
6820 .nmsrs = cr->nmsrs,
6821 .base = cr->base,
6822 .bitmap = (__u8 *)(ulong)cr->bitmap,
6823 };
6824 }
6825
6826 r = kvm_vm_ioctl_set_msr_filter(kvm, &filter);
6827 break;
6828 }
6829 }
6830
6831 return r;
6832 }
6833 #endif
6834
6835 #ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
kvm_arch_suspend_notifier(struct kvm * kvm)6836 static int kvm_arch_suspend_notifier(struct kvm *kvm)
6837 {
6838 struct kvm_vcpu *vcpu;
6839 unsigned long i;
6840
6841 /*
6842 * Ignore the return, marking the guest paused only "fails" if the vCPU
6843 * isn't using kvmclock; continuing on is correct and desirable.
6844 */
6845 kvm_for_each_vcpu(i, vcpu, kvm)
6846 (void)kvm_set_guest_paused(vcpu);
6847
6848 return NOTIFY_DONE;
6849 }
6850
kvm_arch_pm_notifier(struct kvm * kvm,unsigned long state)6851 int kvm_arch_pm_notifier(struct kvm *kvm, unsigned long state)
6852 {
6853 switch (state) {
6854 case PM_HIBERNATION_PREPARE:
6855 case PM_SUSPEND_PREPARE:
6856 return kvm_arch_suspend_notifier(kvm);
6857 }
6858
6859 return NOTIFY_DONE;
6860 }
6861 #endif /* CONFIG_HAVE_KVM_PM_NOTIFIER */
6862
kvm_vm_ioctl_get_clock(struct kvm * kvm,void __user * argp)6863 static int kvm_vm_ioctl_get_clock(struct kvm *kvm, void __user *argp)
6864 {
6865 struct kvm_clock_data data = { 0 };
6866
6867 get_kvmclock(kvm, &data);
6868 if (copy_to_user(argp, &data, sizeof(data)))
6869 return -EFAULT;
6870
6871 return 0;
6872 }
6873
kvm_vm_ioctl_set_clock(struct kvm * kvm,void __user * argp)6874 static int kvm_vm_ioctl_set_clock(struct kvm *kvm, void __user *argp)
6875 {
6876 struct kvm_arch *ka = &kvm->arch;
6877 struct kvm_clock_data data;
6878 u64 now_raw_ns;
6879
6880 if (copy_from_user(&data, argp, sizeof(data)))
6881 return -EFAULT;
6882
6883 /*
6884 * Only KVM_CLOCK_REALTIME is used, but allow passing the
6885 * result of KVM_GET_CLOCK back to KVM_SET_CLOCK.
6886 */
6887 if (data.flags & ~KVM_CLOCK_VALID_FLAGS)
6888 return -EINVAL;
6889
6890 kvm_hv_request_tsc_page_update(kvm);
6891 kvm_start_pvclock_update(kvm);
6892 pvclock_update_vm_gtod_copy(kvm);
6893
6894 /*
6895 * This pairs with kvm_guest_time_update(): when masterclock is
6896 * in use, we use master_kernel_ns + kvmclock_offset to set
6897 * unsigned 'system_time' so if we use get_kvmclock_ns() (which
6898 * is slightly ahead) here we risk going negative on unsigned
6899 * 'system_time' when 'data.clock' is very small.
6900 */
6901 if (data.flags & KVM_CLOCK_REALTIME) {
6902 u64 now_real_ns = ktime_get_real_ns();
6903
6904 /*
6905 * Avoid stepping the kvmclock backwards.
6906 */
6907 if (now_real_ns > data.realtime)
6908 data.clock += now_real_ns - data.realtime;
6909 }
6910
6911 if (ka->use_master_clock)
6912 now_raw_ns = ka->master_kernel_ns;
6913 else
6914 now_raw_ns = get_kvmclock_base_ns();
6915 ka->kvmclock_offset = data.clock - now_raw_ns;
6916 kvm_end_pvclock_update(kvm);
6917 return 0;
6918 }
6919
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)6920 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
6921 {
6922 struct kvm *kvm = filp->private_data;
6923 void __user *argp = (void __user *)arg;
6924 int r = -ENOTTY;
6925
6926 #ifdef CONFIG_KVM_IOAPIC
6927 /*
6928 * This union makes it completely explicit to gcc-3.x
6929 * that these three variables' stack usage should be
6930 * combined, not added together.
6931 */
6932 union {
6933 struct kvm_pit_state ps;
6934 struct kvm_pit_state2 ps2;
6935 struct kvm_pit_config pit_config;
6936 } u;
6937 #endif
6938
6939 switch (ioctl) {
6940 case KVM_SET_TSS_ADDR:
6941 r = kvm_vm_ioctl_set_tss_addr(kvm, arg);
6942 break;
6943 case KVM_SET_IDENTITY_MAP_ADDR: {
6944 u64 ident_addr;
6945
6946 mutex_lock(&kvm->lock);
6947 r = -EINVAL;
6948 if (kvm->created_vcpus)
6949 goto set_identity_unlock;
6950 r = -EFAULT;
6951 if (copy_from_user(&ident_addr, argp, sizeof(ident_addr)))
6952 goto set_identity_unlock;
6953 r = kvm_vm_ioctl_set_identity_map_addr(kvm, ident_addr);
6954 set_identity_unlock:
6955 mutex_unlock(&kvm->lock);
6956 break;
6957 }
6958 case KVM_SET_NR_MMU_PAGES:
6959 r = kvm_vm_ioctl_set_nr_mmu_pages(kvm, arg);
6960 break;
6961 #ifdef CONFIG_KVM_IOAPIC
6962 case KVM_CREATE_IRQCHIP: {
6963 mutex_lock(&kvm->lock);
6964
6965 r = -EEXIST;
6966 if (irqchip_in_kernel(kvm))
6967 goto create_irqchip_unlock;
6968
6969 r = -EINVAL;
6970 if (kvm->created_vcpus)
6971 goto create_irqchip_unlock;
6972
6973 r = kvm_pic_init(kvm);
6974 if (r)
6975 goto create_irqchip_unlock;
6976
6977 r = kvm_ioapic_init(kvm);
6978 if (r) {
6979 kvm_pic_destroy(kvm);
6980 goto create_irqchip_unlock;
6981 }
6982
6983 r = kvm_setup_default_ioapic_and_pic_routing(kvm);
6984 if (r) {
6985 kvm_ioapic_destroy(kvm);
6986 kvm_pic_destroy(kvm);
6987 goto create_irqchip_unlock;
6988 }
6989 /* Write kvm->irq_routing before enabling irqchip_in_kernel. */
6990 smp_wmb();
6991 kvm->arch.irqchip_mode = KVM_IRQCHIP_KERNEL;
6992 kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_ABSENT);
6993 create_irqchip_unlock:
6994 mutex_unlock(&kvm->lock);
6995 break;
6996 }
6997 case KVM_CREATE_PIT:
6998 u.pit_config.flags = KVM_PIT_SPEAKER_DUMMY;
6999 goto create_pit;
7000 case KVM_CREATE_PIT2:
7001 r = -EFAULT;
7002 if (copy_from_user(&u.pit_config, argp,
7003 sizeof(struct kvm_pit_config)))
7004 goto out;
7005 create_pit:
7006 mutex_lock(&kvm->lock);
7007 r = -EEXIST;
7008 if (kvm->arch.vpit)
7009 goto create_pit_unlock;
7010 r = -ENOENT;
7011 if (!pic_in_kernel(kvm))
7012 goto create_pit_unlock;
7013 r = -ENOMEM;
7014 kvm->arch.vpit = kvm_create_pit(kvm, u.pit_config.flags);
7015 if (kvm->arch.vpit)
7016 r = 0;
7017 create_pit_unlock:
7018 mutex_unlock(&kvm->lock);
7019 break;
7020 case KVM_GET_IRQCHIP: {
7021 /* 0: PIC master, 1: PIC slave, 2: IOAPIC */
7022 struct kvm_irqchip *chip;
7023
7024 chip = memdup_user(argp, sizeof(*chip));
7025 if (IS_ERR(chip)) {
7026 r = PTR_ERR(chip);
7027 goto out;
7028 }
7029
7030 r = -ENXIO;
7031 if (!irqchip_full(kvm))
7032 goto get_irqchip_out;
7033 r = kvm_vm_ioctl_get_irqchip(kvm, chip);
7034 if (r)
7035 goto get_irqchip_out;
7036 r = -EFAULT;
7037 if (copy_to_user(argp, chip, sizeof(*chip)))
7038 goto get_irqchip_out;
7039 r = 0;
7040 get_irqchip_out:
7041 kfree(chip);
7042 break;
7043 }
7044 case KVM_SET_IRQCHIP: {
7045 /* 0: PIC master, 1: PIC slave, 2: IOAPIC */
7046 struct kvm_irqchip *chip;
7047
7048 chip = memdup_user(argp, sizeof(*chip));
7049 if (IS_ERR(chip)) {
7050 r = PTR_ERR(chip);
7051 goto out;
7052 }
7053
7054 r = -ENXIO;
7055 if (!irqchip_full(kvm))
7056 goto set_irqchip_out;
7057 r = kvm_vm_ioctl_set_irqchip(kvm, chip);
7058 set_irqchip_out:
7059 kfree(chip);
7060 break;
7061 }
7062 case KVM_GET_PIT: {
7063 r = -EFAULT;
7064 if (copy_from_user(&u.ps, argp, sizeof(struct kvm_pit_state)))
7065 goto out;
7066 r = -ENXIO;
7067 if (!kvm->arch.vpit)
7068 goto out;
7069 r = kvm_vm_ioctl_get_pit(kvm, &u.ps);
7070 if (r)
7071 goto out;
7072 r = -EFAULT;
7073 if (copy_to_user(argp, &u.ps, sizeof(struct kvm_pit_state)))
7074 goto out;
7075 r = 0;
7076 break;
7077 }
7078 case KVM_SET_PIT: {
7079 r = -EFAULT;
7080 if (copy_from_user(&u.ps, argp, sizeof(u.ps)))
7081 goto out;
7082 mutex_lock(&kvm->lock);
7083 r = -ENXIO;
7084 if (!kvm->arch.vpit)
7085 goto set_pit_out;
7086 r = kvm_vm_ioctl_set_pit(kvm, &u.ps);
7087 set_pit_out:
7088 mutex_unlock(&kvm->lock);
7089 break;
7090 }
7091 case KVM_GET_PIT2: {
7092 r = -ENXIO;
7093 if (!kvm->arch.vpit)
7094 goto out;
7095 r = kvm_vm_ioctl_get_pit2(kvm, &u.ps2);
7096 if (r)
7097 goto out;
7098 r = -EFAULT;
7099 if (copy_to_user(argp, &u.ps2, sizeof(u.ps2)))
7100 goto out;
7101 r = 0;
7102 break;
7103 }
7104 case KVM_SET_PIT2: {
7105 r = -EFAULT;
7106 if (copy_from_user(&u.ps2, argp, sizeof(u.ps2)))
7107 goto out;
7108 mutex_lock(&kvm->lock);
7109 r = -ENXIO;
7110 if (!kvm->arch.vpit)
7111 goto set_pit2_out;
7112 r = kvm_vm_ioctl_set_pit2(kvm, &u.ps2);
7113 set_pit2_out:
7114 mutex_unlock(&kvm->lock);
7115 break;
7116 }
7117 case KVM_REINJECT_CONTROL: {
7118 struct kvm_reinject_control control;
7119 r = -EFAULT;
7120 if (copy_from_user(&control, argp, sizeof(control)))
7121 goto out;
7122 r = -ENXIO;
7123 if (!kvm->arch.vpit)
7124 goto out;
7125 r = kvm_vm_ioctl_reinject(kvm, &control);
7126 break;
7127 }
7128 #endif
7129 case KVM_SET_BOOT_CPU_ID:
7130 r = 0;
7131 mutex_lock(&kvm->lock);
7132 if (kvm->created_vcpus)
7133 r = -EBUSY;
7134 else if (arg > KVM_MAX_VCPU_IDS ||
7135 (kvm->arch.max_vcpu_ids && arg > kvm->arch.max_vcpu_ids))
7136 r = -EINVAL;
7137 else
7138 kvm->arch.bsp_vcpu_id = arg;
7139 mutex_unlock(&kvm->lock);
7140 break;
7141 #ifdef CONFIG_KVM_XEN
7142 case KVM_XEN_HVM_CONFIG: {
7143 struct kvm_xen_hvm_config xhc;
7144 r = -EFAULT;
7145 if (copy_from_user(&xhc, argp, sizeof(xhc)))
7146 goto out;
7147 r = kvm_xen_hvm_config(kvm, &xhc);
7148 break;
7149 }
7150 case KVM_XEN_HVM_GET_ATTR: {
7151 struct kvm_xen_hvm_attr xha;
7152
7153 r = -EFAULT;
7154 if (copy_from_user(&xha, argp, sizeof(xha)))
7155 goto out;
7156 r = kvm_xen_hvm_get_attr(kvm, &xha);
7157 if (!r && copy_to_user(argp, &xha, sizeof(xha)))
7158 r = -EFAULT;
7159 break;
7160 }
7161 case KVM_XEN_HVM_SET_ATTR: {
7162 struct kvm_xen_hvm_attr xha;
7163
7164 r = -EFAULT;
7165 if (copy_from_user(&xha, argp, sizeof(xha)))
7166 goto out;
7167 r = kvm_xen_hvm_set_attr(kvm, &xha);
7168 break;
7169 }
7170 case KVM_XEN_HVM_EVTCHN_SEND: {
7171 struct kvm_irq_routing_xen_evtchn uxe;
7172
7173 r = -EFAULT;
7174 if (copy_from_user(&uxe, argp, sizeof(uxe)))
7175 goto out;
7176 r = kvm_xen_hvm_evtchn_send(kvm, &uxe);
7177 break;
7178 }
7179 #endif
7180 case KVM_SET_CLOCK:
7181 r = kvm_vm_ioctl_set_clock(kvm, argp);
7182 break;
7183 case KVM_GET_CLOCK:
7184 r = kvm_vm_ioctl_get_clock(kvm, argp);
7185 break;
7186 case KVM_SET_TSC_KHZ: {
7187 u32 user_tsc_khz;
7188
7189 r = -EINVAL;
7190 user_tsc_khz = (u32)arg;
7191
7192 if (kvm_caps.has_tsc_control &&
7193 user_tsc_khz >= kvm_caps.max_guest_tsc_khz)
7194 goto out;
7195
7196 if (user_tsc_khz == 0)
7197 user_tsc_khz = tsc_khz;
7198
7199 mutex_lock(&kvm->lock);
7200 if (!kvm->created_vcpus) {
7201 WRITE_ONCE(kvm->arch.default_tsc_khz, user_tsc_khz);
7202 r = 0;
7203 }
7204 mutex_unlock(&kvm->lock);
7205 goto out;
7206 }
7207 case KVM_GET_TSC_KHZ: {
7208 r = READ_ONCE(kvm->arch.default_tsc_khz);
7209 goto out;
7210 }
7211 case KVM_MEMORY_ENCRYPT_OP:
7212 r = -ENOTTY;
7213 if (!kvm_x86_ops.mem_enc_ioctl)
7214 goto out;
7215
7216 r = kvm_x86_call(mem_enc_ioctl)(kvm, argp);
7217 break;
7218 case KVM_MEMORY_ENCRYPT_REG_REGION: {
7219 struct kvm_enc_region region;
7220
7221 r = -EFAULT;
7222 if (copy_from_user(®ion, argp, sizeof(region)))
7223 goto out;
7224
7225 r = -ENOTTY;
7226 if (!kvm_x86_ops.mem_enc_register_region)
7227 goto out;
7228
7229 r = kvm_x86_call(mem_enc_register_region)(kvm, ®ion);
7230 break;
7231 }
7232 case KVM_MEMORY_ENCRYPT_UNREG_REGION: {
7233 struct kvm_enc_region region;
7234
7235 r = -EFAULT;
7236 if (copy_from_user(®ion, argp, sizeof(region)))
7237 goto out;
7238
7239 r = -ENOTTY;
7240 if (!kvm_x86_ops.mem_enc_unregister_region)
7241 goto out;
7242
7243 r = kvm_x86_call(mem_enc_unregister_region)(kvm, ®ion);
7244 break;
7245 }
7246 #ifdef CONFIG_KVM_HYPERV
7247 case KVM_HYPERV_EVENTFD: {
7248 struct kvm_hyperv_eventfd hvevfd;
7249
7250 r = -EFAULT;
7251 if (copy_from_user(&hvevfd, argp, sizeof(hvevfd)))
7252 goto out;
7253 r = kvm_vm_ioctl_hv_eventfd(kvm, &hvevfd);
7254 break;
7255 }
7256 #endif
7257 case KVM_SET_PMU_EVENT_FILTER:
7258 r = kvm_vm_ioctl_set_pmu_event_filter(kvm, argp);
7259 break;
7260 case KVM_X86_SET_MSR_FILTER: {
7261 struct kvm_msr_filter __user *user_msr_filter = argp;
7262 struct kvm_msr_filter filter;
7263
7264 if (copy_from_user(&filter, user_msr_filter, sizeof(filter)))
7265 return -EFAULT;
7266
7267 r = kvm_vm_ioctl_set_msr_filter(kvm, &filter);
7268 break;
7269 }
7270 default:
7271 r = -ENOTTY;
7272 }
7273 out:
7274 return r;
7275 }
7276
kvm_probe_feature_msr(u32 msr_index)7277 static void kvm_probe_feature_msr(u32 msr_index)
7278 {
7279 u64 data;
7280
7281 if (kvm_get_feature_msr(NULL, msr_index, &data, true))
7282 return;
7283
7284 msr_based_features[num_msr_based_features++] = msr_index;
7285 }
7286
kvm_probe_msr_to_save(u32 msr_index)7287 static void kvm_probe_msr_to_save(u32 msr_index)
7288 {
7289 u32 dummy[2];
7290
7291 if (rdmsr_safe(msr_index, &dummy[0], &dummy[1]))
7292 return;
7293
7294 /*
7295 * Even MSRs that are valid in the host may not be exposed to guests in
7296 * some cases.
7297 */
7298 switch (msr_index) {
7299 case MSR_IA32_BNDCFGS:
7300 if (!kvm_mpx_supported())
7301 return;
7302 break;
7303 case MSR_TSC_AUX:
7304 if (!kvm_cpu_cap_has(X86_FEATURE_RDTSCP) &&
7305 !kvm_cpu_cap_has(X86_FEATURE_RDPID))
7306 return;
7307 break;
7308 case MSR_IA32_UMWAIT_CONTROL:
7309 if (!kvm_cpu_cap_has(X86_FEATURE_WAITPKG))
7310 return;
7311 break;
7312 case MSR_IA32_RTIT_CTL:
7313 case MSR_IA32_RTIT_STATUS:
7314 if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT))
7315 return;
7316 break;
7317 case MSR_IA32_RTIT_CR3_MATCH:
7318 if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) ||
7319 !intel_pt_validate_hw_cap(PT_CAP_cr3_filtering))
7320 return;
7321 break;
7322 case MSR_IA32_RTIT_OUTPUT_BASE:
7323 case MSR_IA32_RTIT_OUTPUT_MASK:
7324 if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) ||
7325 (!intel_pt_validate_hw_cap(PT_CAP_topa_output) &&
7326 !intel_pt_validate_hw_cap(PT_CAP_single_range_output)))
7327 return;
7328 break;
7329 case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
7330 if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) ||
7331 (msr_index - MSR_IA32_RTIT_ADDR0_A >=
7332 intel_pt_validate_hw_cap(PT_CAP_num_address_ranges) * 2))
7333 return;
7334 break;
7335 case MSR_ARCH_PERFMON_PERFCTR0 ...
7336 MSR_ARCH_PERFMON_PERFCTR0 + KVM_MAX_NR_GP_COUNTERS - 1:
7337 if (msr_index - MSR_ARCH_PERFMON_PERFCTR0 >=
7338 kvm_pmu_cap.num_counters_gp)
7339 return;
7340 break;
7341 case MSR_ARCH_PERFMON_EVENTSEL0 ...
7342 MSR_ARCH_PERFMON_EVENTSEL0 + KVM_MAX_NR_GP_COUNTERS - 1:
7343 if (msr_index - MSR_ARCH_PERFMON_EVENTSEL0 >=
7344 kvm_pmu_cap.num_counters_gp)
7345 return;
7346 break;
7347 case MSR_ARCH_PERFMON_FIXED_CTR0 ...
7348 MSR_ARCH_PERFMON_FIXED_CTR0 + KVM_MAX_NR_FIXED_COUNTERS - 1:
7349 if (msr_index - MSR_ARCH_PERFMON_FIXED_CTR0 >=
7350 kvm_pmu_cap.num_counters_fixed)
7351 return;
7352 break;
7353 case MSR_AMD64_PERF_CNTR_GLOBAL_CTL:
7354 case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS:
7355 case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR:
7356 if (!kvm_cpu_cap_has(X86_FEATURE_PERFMON_V2))
7357 return;
7358 break;
7359 case MSR_IA32_XFD:
7360 case MSR_IA32_XFD_ERR:
7361 if (!kvm_cpu_cap_has(X86_FEATURE_XFD))
7362 return;
7363 break;
7364 case MSR_IA32_TSX_CTRL:
7365 if (!(kvm_get_arch_capabilities() & ARCH_CAP_TSX_CTRL_MSR))
7366 return;
7367 break;
7368 default:
7369 break;
7370 }
7371
7372 msrs_to_save[num_msrs_to_save++] = msr_index;
7373 }
7374
kvm_init_msr_lists(void)7375 static void kvm_init_msr_lists(void)
7376 {
7377 unsigned i;
7378
7379 BUILD_BUG_ON_MSG(KVM_MAX_NR_FIXED_COUNTERS != 3,
7380 "Please update the fixed PMCs in msrs_to_save_pmu[]");
7381
7382 num_msrs_to_save = 0;
7383 num_emulated_msrs = 0;
7384 num_msr_based_features = 0;
7385
7386 for (i = 0; i < ARRAY_SIZE(msrs_to_save_base); i++)
7387 kvm_probe_msr_to_save(msrs_to_save_base[i]);
7388
7389 if (enable_pmu) {
7390 for (i = 0; i < ARRAY_SIZE(msrs_to_save_pmu); i++)
7391 kvm_probe_msr_to_save(msrs_to_save_pmu[i]);
7392 }
7393
7394 for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) {
7395 if (!kvm_x86_call(has_emulated_msr)(NULL,
7396 emulated_msrs_all[i]))
7397 continue;
7398
7399 emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i];
7400 }
7401
7402 for (i = KVM_FIRST_EMULATED_VMX_MSR; i <= KVM_LAST_EMULATED_VMX_MSR; i++)
7403 kvm_probe_feature_msr(i);
7404
7405 for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++)
7406 kvm_probe_feature_msr(msr_based_features_all_except_vmx[i]);
7407 }
7408
vcpu_mmio_write(struct kvm_vcpu * vcpu,gpa_t addr,int len,const void * v)7409 static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len,
7410 const void *v)
7411 {
7412 int handled = 0;
7413 int n;
7414
7415 do {
7416 n = min(len, 8);
7417 if (!(lapic_in_kernel(vcpu) &&
7418 !kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, addr, n, v))
7419 && kvm_io_bus_write(vcpu, KVM_MMIO_BUS, addr, n, v))
7420 break;
7421 handled += n;
7422 addr += n;
7423 len -= n;
7424 v += n;
7425 } while (len);
7426
7427 return handled;
7428 }
7429
vcpu_mmio_read(struct kvm_vcpu * vcpu,gpa_t addr,int len,void * v)7430 static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v)
7431 {
7432 int handled = 0;
7433 int n;
7434
7435 do {
7436 n = min(len, 8);
7437 if (!(lapic_in_kernel(vcpu) &&
7438 !kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev,
7439 addr, n, v))
7440 && kvm_io_bus_read(vcpu, KVM_MMIO_BUS, addr, n, v))
7441 break;
7442 trace_kvm_mmio(KVM_TRACE_MMIO_READ, n, addr, v);
7443 handled += n;
7444 addr += n;
7445 len -= n;
7446 v += n;
7447 } while (len);
7448
7449 return handled;
7450 }
7451
kvm_set_segment(struct kvm_vcpu * vcpu,struct kvm_segment * var,int seg)7452 void kvm_set_segment(struct kvm_vcpu *vcpu,
7453 struct kvm_segment *var, int seg)
7454 {
7455 kvm_x86_call(set_segment)(vcpu, var, seg);
7456 }
7457
kvm_get_segment(struct kvm_vcpu * vcpu,struct kvm_segment * var,int seg)7458 void kvm_get_segment(struct kvm_vcpu *vcpu,
7459 struct kvm_segment *var, int seg)
7460 {
7461 kvm_x86_call(get_segment)(vcpu, var, seg);
7462 }
7463
translate_nested_gpa(struct kvm_vcpu * vcpu,gpa_t gpa,u64 access,struct x86_exception * exception)7464 gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
7465 struct x86_exception *exception)
7466 {
7467 struct kvm_mmu *mmu = vcpu->arch.mmu;
7468 gpa_t t_gpa;
7469
7470 BUG_ON(!mmu_is_nested(vcpu));
7471
7472 /* NPT walks are always user-walks */
7473 access |= PFERR_USER_MASK;
7474 t_gpa = mmu->gva_to_gpa(vcpu, mmu, gpa, access, exception);
7475
7476 return t_gpa;
7477 }
7478
kvm_mmu_gva_to_gpa_read(struct kvm_vcpu * vcpu,gva_t gva,struct x86_exception * exception)7479 gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva,
7480 struct x86_exception *exception)
7481 {
7482 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7483
7484 u64 access = (kvm_x86_call(get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7485 return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
7486 }
7487 EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_read);
7488
kvm_mmu_gva_to_gpa_write(struct kvm_vcpu * vcpu,gva_t gva,struct x86_exception * exception)7489 gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva,
7490 struct x86_exception *exception)
7491 {
7492 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7493
7494 u64 access = (kvm_x86_call(get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7495 access |= PFERR_WRITE_MASK;
7496 return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
7497 }
7498 EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_write);
7499
7500 /* uses this to access any guest's mapped memory without checking CPL */
kvm_mmu_gva_to_gpa_system(struct kvm_vcpu * vcpu,gva_t gva,struct x86_exception * exception)7501 gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva,
7502 struct x86_exception *exception)
7503 {
7504 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7505
7506 return mmu->gva_to_gpa(vcpu, mmu, gva, 0, exception);
7507 }
7508
kvm_read_guest_virt_helper(gva_t addr,void * val,unsigned int bytes,struct kvm_vcpu * vcpu,u64 access,struct x86_exception * exception)7509 static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
7510 struct kvm_vcpu *vcpu, u64 access,
7511 struct x86_exception *exception)
7512 {
7513 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7514 void *data = val;
7515 int r = X86EMUL_CONTINUE;
7516
7517 while (bytes) {
7518 gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access, exception);
7519 unsigned offset = addr & (PAGE_SIZE-1);
7520 unsigned toread = min(bytes, (unsigned)PAGE_SIZE - offset);
7521 int ret;
7522
7523 if (gpa == INVALID_GPA)
7524 return X86EMUL_PROPAGATE_FAULT;
7525 ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, data,
7526 offset, toread);
7527 if (ret < 0) {
7528 r = X86EMUL_IO_NEEDED;
7529 goto out;
7530 }
7531
7532 bytes -= toread;
7533 data += toread;
7534 addr += toread;
7535 }
7536 out:
7537 return r;
7538 }
7539
7540 /* used for instruction fetching */
kvm_fetch_guest_virt(struct x86_emulate_ctxt * ctxt,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception)7541 static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt,
7542 gva_t addr, void *val, unsigned int bytes,
7543 struct x86_exception *exception)
7544 {
7545 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7546 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7547 u64 access = (kvm_x86_call(get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7548 unsigned offset;
7549 int ret;
7550
7551 /* Inline kvm_read_guest_virt_helper for speed. */
7552 gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access|PFERR_FETCH_MASK,
7553 exception);
7554 if (unlikely(gpa == INVALID_GPA))
7555 return X86EMUL_PROPAGATE_FAULT;
7556
7557 offset = addr & (PAGE_SIZE-1);
7558 if (WARN_ON(offset + bytes > PAGE_SIZE))
7559 bytes = (unsigned)PAGE_SIZE - offset;
7560 ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, val,
7561 offset, bytes);
7562 if (unlikely(ret < 0))
7563 return X86EMUL_IO_NEEDED;
7564
7565 return X86EMUL_CONTINUE;
7566 }
7567
kvm_read_guest_virt(struct kvm_vcpu * vcpu,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception)7568 int kvm_read_guest_virt(struct kvm_vcpu *vcpu,
7569 gva_t addr, void *val, unsigned int bytes,
7570 struct x86_exception *exception)
7571 {
7572 u64 access = (kvm_x86_call(get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7573
7574 /*
7575 * FIXME: this should call handle_emulation_failure if X86EMUL_IO_NEEDED
7576 * is returned, but our callers are not ready for that and they blindly
7577 * call kvm_inject_page_fault. Ensure that they at least do not leak
7578 * uninitialized kernel stack memory into cr2 and error code.
7579 */
7580 memset(exception, 0, sizeof(*exception));
7581 return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access,
7582 exception);
7583 }
7584 EXPORT_SYMBOL_GPL(kvm_read_guest_virt);
7585
emulator_read_std(struct x86_emulate_ctxt * ctxt,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception,bool system)7586 static int emulator_read_std(struct x86_emulate_ctxt *ctxt,
7587 gva_t addr, void *val, unsigned int bytes,
7588 struct x86_exception *exception, bool system)
7589 {
7590 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7591 u64 access = 0;
7592
7593 if (system)
7594 access |= PFERR_IMPLICIT_ACCESS;
7595 else if (kvm_x86_call(get_cpl)(vcpu) == 3)
7596 access |= PFERR_USER_MASK;
7597
7598 return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception);
7599 }
7600
kvm_write_guest_virt_helper(gva_t addr,void * val,unsigned int bytes,struct kvm_vcpu * vcpu,u64 access,struct x86_exception * exception)7601 static int kvm_write_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
7602 struct kvm_vcpu *vcpu, u64 access,
7603 struct x86_exception *exception)
7604 {
7605 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7606 void *data = val;
7607 int r = X86EMUL_CONTINUE;
7608
7609 while (bytes) {
7610 gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access, exception);
7611 unsigned offset = addr & (PAGE_SIZE-1);
7612 unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset);
7613 int ret;
7614
7615 if (gpa == INVALID_GPA)
7616 return X86EMUL_PROPAGATE_FAULT;
7617 ret = kvm_vcpu_write_guest(vcpu, gpa, data, towrite);
7618 if (ret < 0) {
7619 r = X86EMUL_IO_NEEDED;
7620 goto out;
7621 }
7622
7623 bytes -= towrite;
7624 data += towrite;
7625 addr += towrite;
7626 }
7627 out:
7628 return r;
7629 }
7630
emulator_write_std(struct x86_emulate_ctxt * ctxt,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception,bool system)7631 static int emulator_write_std(struct x86_emulate_ctxt *ctxt, gva_t addr, void *val,
7632 unsigned int bytes, struct x86_exception *exception,
7633 bool system)
7634 {
7635 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7636 u64 access = PFERR_WRITE_MASK;
7637
7638 if (system)
7639 access |= PFERR_IMPLICIT_ACCESS;
7640 else if (kvm_x86_call(get_cpl)(vcpu) == 3)
7641 access |= PFERR_USER_MASK;
7642
7643 return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
7644 access, exception);
7645 }
7646
kvm_write_guest_virt_system(struct kvm_vcpu * vcpu,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception)7647 int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val,
7648 unsigned int bytes, struct x86_exception *exception)
7649 {
7650 /* kvm_write_guest_virt_system can pull in tons of pages. */
7651 vcpu->arch.l1tf_flush_l1d = true;
7652
7653 return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
7654 PFERR_WRITE_MASK, exception);
7655 }
7656 EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system);
7657
kvm_check_emulate_insn(struct kvm_vcpu * vcpu,int emul_type,void * insn,int insn_len)7658 static int kvm_check_emulate_insn(struct kvm_vcpu *vcpu, int emul_type,
7659 void *insn, int insn_len)
7660 {
7661 return kvm_x86_call(check_emulate_instruction)(vcpu, emul_type,
7662 insn, insn_len);
7663 }
7664
handle_ud(struct kvm_vcpu * vcpu)7665 int handle_ud(struct kvm_vcpu *vcpu)
7666 {
7667 static const char kvm_emulate_prefix[] = { __KVM_EMULATE_PREFIX };
7668 int fep_flags = READ_ONCE(force_emulation_prefix);
7669 int emul_type = EMULTYPE_TRAP_UD;
7670 char sig[5]; /* ud2; .ascii "kvm" */
7671 struct x86_exception e;
7672 int r;
7673
7674 r = kvm_check_emulate_insn(vcpu, emul_type, NULL, 0);
7675 if (r != X86EMUL_CONTINUE)
7676 return 1;
7677
7678 if (fep_flags &&
7679 kvm_read_guest_virt(vcpu, kvm_get_linear_rip(vcpu),
7680 sig, sizeof(sig), &e) == 0 &&
7681 memcmp(sig, kvm_emulate_prefix, sizeof(sig)) == 0) {
7682 if (fep_flags & KVM_FEP_CLEAR_RFLAGS_RF)
7683 kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) & ~X86_EFLAGS_RF);
7684 kvm_rip_write(vcpu, kvm_rip_read(vcpu) + sizeof(sig));
7685 emul_type = EMULTYPE_TRAP_UD_FORCED;
7686 }
7687
7688 return kvm_emulate_instruction(vcpu, emul_type);
7689 }
7690 EXPORT_SYMBOL_GPL(handle_ud);
7691
vcpu_is_mmio_gpa(struct kvm_vcpu * vcpu,unsigned long gva,gpa_t gpa,bool write)7692 static int vcpu_is_mmio_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
7693 gpa_t gpa, bool write)
7694 {
7695 /* For APIC access vmexit */
7696 if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
7697 return 1;
7698
7699 if (vcpu_match_mmio_gpa(vcpu, gpa)) {
7700 trace_vcpu_match_mmio(gva, gpa, write, true);
7701 return 1;
7702 }
7703
7704 return 0;
7705 }
7706
vcpu_mmio_gva_to_gpa(struct kvm_vcpu * vcpu,unsigned long gva,gpa_t * gpa,struct x86_exception * exception,bool write)7707 static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
7708 gpa_t *gpa, struct x86_exception *exception,
7709 bool write)
7710 {
7711 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7712 u64 access = ((kvm_x86_call(get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0)
7713 | (write ? PFERR_WRITE_MASK : 0);
7714
7715 /*
7716 * currently PKRU is only applied to ept enabled guest so
7717 * there is no pkey in EPT page table for L1 guest or EPT
7718 * shadow page table for L2 guest.
7719 */
7720 if (vcpu_match_mmio_gva(vcpu, gva) && (!is_paging(vcpu) ||
7721 !permission_fault(vcpu, vcpu->arch.walk_mmu,
7722 vcpu->arch.mmio_access, 0, access))) {
7723 *gpa = vcpu->arch.mmio_gfn << PAGE_SHIFT |
7724 (gva & (PAGE_SIZE - 1));
7725 trace_vcpu_match_mmio(gva, *gpa, write, false);
7726 return 1;
7727 }
7728
7729 *gpa = mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
7730
7731 if (*gpa == INVALID_GPA)
7732 return -1;
7733
7734 return vcpu_is_mmio_gpa(vcpu, gva, *gpa, write);
7735 }
7736
emulator_write_phys(struct kvm_vcpu * vcpu,gpa_t gpa,const void * val,int bytes)7737 int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
7738 const void *val, int bytes)
7739 {
7740 int ret;
7741
7742 ret = kvm_vcpu_write_guest(vcpu, gpa, val, bytes);
7743 if (ret < 0)
7744 return 0;
7745 kvm_page_track_write(vcpu, gpa, val, bytes);
7746 return 1;
7747 }
7748
7749 struct read_write_emulator_ops {
7750 int (*read_write_prepare)(struct kvm_vcpu *vcpu, void *val,
7751 int bytes);
7752 int (*read_write_emulate)(struct kvm_vcpu *vcpu, gpa_t gpa,
7753 void *val, int bytes);
7754 int (*read_write_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
7755 int bytes, void *val);
7756 int (*read_write_exit_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
7757 void *val, int bytes);
7758 bool write;
7759 };
7760
read_prepare(struct kvm_vcpu * vcpu,void * val,int bytes)7761 static int read_prepare(struct kvm_vcpu *vcpu, void *val, int bytes)
7762 {
7763 if (vcpu->mmio_read_completed) {
7764 trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes,
7765 vcpu->mmio_fragments[0].gpa, val);
7766 vcpu->mmio_read_completed = 0;
7767 return 1;
7768 }
7769
7770 return 0;
7771 }
7772
read_emulate(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7773 static int read_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
7774 void *val, int bytes)
7775 {
7776 return !kvm_vcpu_read_guest(vcpu, gpa, val, bytes);
7777 }
7778
write_emulate(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7779 static int write_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
7780 void *val, int bytes)
7781 {
7782 return emulator_write_phys(vcpu, gpa, val, bytes);
7783 }
7784
write_mmio(struct kvm_vcpu * vcpu,gpa_t gpa,int bytes,void * val)7785 static int write_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes, void *val)
7786 {
7787 trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, val);
7788 return vcpu_mmio_write(vcpu, gpa, bytes, val);
7789 }
7790
read_exit_mmio(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7791 static int read_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
7792 void *val, int bytes)
7793 {
7794 trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, NULL);
7795 return X86EMUL_IO_NEEDED;
7796 }
7797
write_exit_mmio(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7798 static int write_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
7799 void *val, int bytes)
7800 {
7801 struct kvm_mmio_fragment *frag = &vcpu->mmio_fragments[0];
7802
7803 memcpy(vcpu->run->mmio.data, frag->data, min(8u, frag->len));
7804 return X86EMUL_CONTINUE;
7805 }
7806
7807 static const struct read_write_emulator_ops read_emultor = {
7808 .read_write_prepare = read_prepare,
7809 .read_write_emulate = read_emulate,
7810 .read_write_mmio = vcpu_mmio_read,
7811 .read_write_exit_mmio = read_exit_mmio,
7812 };
7813
7814 static const struct read_write_emulator_ops write_emultor = {
7815 .read_write_emulate = write_emulate,
7816 .read_write_mmio = write_mmio,
7817 .read_write_exit_mmio = write_exit_mmio,
7818 .write = true,
7819 };
7820
emulator_read_write_onepage(unsigned long addr,void * val,unsigned int bytes,struct x86_exception * exception,struct kvm_vcpu * vcpu,const struct read_write_emulator_ops * ops)7821 static int emulator_read_write_onepage(unsigned long addr, void *val,
7822 unsigned int bytes,
7823 struct x86_exception *exception,
7824 struct kvm_vcpu *vcpu,
7825 const struct read_write_emulator_ops *ops)
7826 {
7827 gpa_t gpa;
7828 int handled, ret;
7829 bool write = ops->write;
7830 struct kvm_mmio_fragment *frag;
7831 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
7832
7833 /*
7834 * If the exit was due to a NPF we may already have a GPA.
7835 * If the GPA is present, use it to avoid the GVA to GPA table walk.
7836 * Note, this cannot be used on string operations since string
7837 * operation using rep will only have the initial GPA from the NPF
7838 * occurred.
7839 */
7840 if (ctxt->gpa_available && emulator_can_use_gpa(ctxt) &&
7841 (addr & ~PAGE_MASK) == (ctxt->gpa_val & ~PAGE_MASK)) {
7842 gpa = ctxt->gpa_val;
7843 ret = vcpu_is_mmio_gpa(vcpu, addr, gpa, write);
7844 } else {
7845 ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, write);
7846 if (ret < 0)
7847 return X86EMUL_PROPAGATE_FAULT;
7848 }
7849
7850 if (!ret && ops->read_write_emulate(vcpu, gpa, val, bytes))
7851 return X86EMUL_CONTINUE;
7852
7853 /*
7854 * Is this MMIO handled locally?
7855 */
7856 handled = ops->read_write_mmio(vcpu, gpa, bytes, val);
7857 if (handled == bytes)
7858 return X86EMUL_CONTINUE;
7859
7860 gpa += handled;
7861 bytes -= handled;
7862 val += handled;
7863
7864 WARN_ON(vcpu->mmio_nr_fragments >= KVM_MAX_MMIO_FRAGMENTS);
7865 frag = &vcpu->mmio_fragments[vcpu->mmio_nr_fragments++];
7866 frag->gpa = gpa;
7867 frag->data = val;
7868 frag->len = bytes;
7869 return X86EMUL_CONTINUE;
7870 }
7871
emulator_read_write(struct x86_emulate_ctxt * ctxt,unsigned long addr,void * val,unsigned int bytes,struct x86_exception * exception,const struct read_write_emulator_ops * ops)7872 static int emulator_read_write(struct x86_emulate_ctxt *ctxt,
7873 unsigned long addr,
7874 void *val, unsigned int bytes,
7875 struct x86_exception *exception,
7876 const struct read_write_emulator_ops *ops)
7877 {
7878 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7879 gpa_t gpa;
7880 int rc;
7881
7882 if (ops->read_write_prepare &&
7883 ops->read_write_prepare(vcpu, val, bytes))
7884 return X86EMUL_CONTINUE;
7885
7886 vcpu->mmio_nr_fragments = 0;
7887
7888 /* Crossing a page boundary? */
7889 if (((addr + bytes - 1) ^ addr) & PAGE_MASK) {
7890 int now;
7891
7892 now = -addr & ~PAGE_MASK;
7893 rc = emulator_read_write_onepage(addr, val, now, exception,
7894 vcpu, ops);
7895
7896 if (rc != X86EMUL_CONTINUE)
7897 return rc;
7898 addr += now;
7899 if (ctxt->mode != X86EMUL_MODE_PROT64)
7900 addr = (u32)addr;
7901 val += now;
7902 bytes -= now;
7903 }
7904
7905 rc = emulator_read_write_onepage(addr, val, bytes, exception,
7906 vcpu, ops);
7907 if (rc != X86EMUL_CONTINUE)
7908 return rc;
7909
7910 if (!vcpu->mmio_nr_fragments)
7911 return X86EMUL_CONTINUE;
7912
7913 gpa = vcpu->mmio_fragments[0].gpa;
7914
7915 vcpu->mmio_needed = 1;
7916 vcpu->mmio_cur_fragment = 0;
7917
7918 vcpu->run->mmio.len = min(8u, vcpu->mmio_fragments[0].len);
7919 vcpu->run->mmio.is_write = vcpu->mmio_is_write = ops->write;
7920 vcpu->run->exit_reason = KVM_EXIT_MMIO;
7921 vcpu->run->mmio.phys_addr = gpa;
7922
7923 return ops->read_write_exit_mmio(vcpu, gpa, val, bytes);
7924 }
7925
emulator_read_emulated(struct x86_emulate_ctxt * ctxt,unsigned long addr,void * val,unsigned int bytes,struct x86_exception * exception)7926 static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
7927 unsigned long addr,
7928 void *val,
7929 unsigned int bytes,
7930 struct x86_exception *exception)
7931 {
7932 return emulator_read_write(ctxt, addr, val, bytes,
7933 exception, &read_emultor);
7934 }
7935
emulator_write_emulated(struct x86_emulate_ctxt * ctxt,unsigned long addr,const void * val,unsigned int bytes,struct x86_exception * exception)7936 static int emulator_write_emulated(struct x86_emulate_ctxt *ctxt,
7937 unsigned long addr,
7938 const void *val,
7939 unsigned int bytes,
7940 struct x86_exception *exception)
7941 {
7942 return emulator_read_write(ctxt, addr, (void *)val, bytes,
7943 exception, &write_emultor);
7944 }
7945
7946 #define emulator_try_cmpxchg_user(t, ptr, old, new) \
7947 (__try_cmpxchg_user((t __user *)(ptr), (t *)(old), *(t *)(new), efault ## t))
7948
emulator_cmpxchg_emulated(struct x86_emulate_ctxt * ctxt,unsigned long addr,const void * old,const void * new,unsigned int bytes,struct x86_exception * exception)7949 static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt,
7950 unsigned long addr,
7951 const void *old,
7952 const void *new,
7953 unsigned int bytes,
7954 struct x86_exception *exception)
7955 {
7956 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7957 u64 page_line_mask;
7958 unsigned long hva;
7959 gpa_t gpa;
7960 int r;
7961
7962 /* guests cmpxchg8b have to be emulated atomically */
7963 if (bytes > 8 || (bytes & (bytes - 1)))
7964 goto emul_write;
7965
7966 gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, NULL);
7967
7968 if (gpa == INVALID_GPA ||
7969 (gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
7970 goto emul_write;
7971
7972 /*
7973 * Emulate the atomic as a straight write to avoid #AC if SLD is
7974 * enabled in the host and the access splits a cache line.
7975 */
7976 if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
7977 page_line_mask = ~(cache_line_size() - 1);
7978 else
7979 page_line_mask = PAGE_MASK;
7980
7981 if (((gpa + bytes - 1) & page_line_mask) != (gpa & page_line_mask))
7982 goto emul_write;
7983
7984 hva = kvm_vcpu_gfn_to_hva(vcpu, gpa_to_gfn(gpa));
7985 if (kvm_is_error_hva(hva))
7986 goto emul_write;
7987
7988 hva += offset_in_page(gpa);
7989
7990 switch (bytes) {
7991 case 1:
7992 r = emulator_try_cmpxchg_user(u8, hva, old, new);
7993 break;
7994 case 2:
7995 r = emulator_try_cmpxchg_user(u16, hva, old, new);
7996 break;
7997 case 4:
7998 r = emulator_try_cmpxchg_user(u32, hva, old, new);
7999 break;
8000 case 8:
8001 r = emulator_try_cmpxchg_user(u64, hva, old, new);
8002 break;
8003 default:
8004 BUG();
8005 }
8006
8007 if (r < 0)
8008 return X86EMUL_UNHANDLEABLE;
8009
8010 /*
8011 * Mark the page dirty _before_ checking whether or not the CMPXCHG was
8012 * successful, as the old value is written back on failure. Note, for
8013 * live migration, this is unnecessarily conservative as CMPXCHG writes
8014 * back the original value and the access is atomic, but KVM's ABI is
8015 * that all writes are dirty logged, regardless of the value written.
8016 */
8017 kvm_vcpu_mark_page_dirty(vcpu, gpa_to_gfn(gpa));
8018
8019 if (r)
8020 return X86EMUL_CMPXCHG_FAILED;
8021
8022 kvm_page_track_write(vcpu, gpa, new, bytes);
8023
8024 return X86EMUL_CONTINUE;
8025
8026 emul_write:
8027 pr_warn_once("emulating exchange as write\n");
8028
8029 return emulator_write_emulated(ctxt, addr, new, bytes, exception);
8030 }
8031
emulator_pio_in_out(struct kvm_vcpu * vcpu,int size,unsigned short port,void * data,unsigned int count,bool in)8032 static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size,
8033 unsigned short port, void *data,
8034 unsigned int count, bool in)
8035 {
8036 unsigned i;
8037 int r;
8038
8039 WARN_ON_ONCE(vcpu->arch.pio.count);
8040 for (i = 0; i < count; i++) {
8041 if (in)
8042 r = kvm_io_bus_read(vcpu, KVM_PIO_BUS, port, size, data);
8043 else
8044 r = kvm_io_bus_write(vcpu, KVM_PIO_BUS, port, size, data);
8045
8046 if (r) {
8047 if (i == 0)
8048 goto userspace_io;
8049
8050 /*
8051 * Userspace must have unregistered the device while PIO
8052 * was running. Drop writes / read as 0.
8053 */
8054 if (in)
8055 memset(data, 0, size * (count - i));
8056 break;
8057 }
8058
8059 data += size;
8060 }
8061 return 1;
8062
8063 userspace_io:
8064 vcpu->arch.pio.port = port;
8065 vcpu->arch.pio.in = in;
8066 vcpu->arch.pio.count = count;
8067 vcpu->arch.pio.size = size;
8068
8069 if (in)
8070 memset(vcpu->arch.pio_data, 0, size * count);
8071 else
8072 memcpy(vcpu->arch.pio_data, data, size * count);
8073
8074 vcpu->run->exit_reason = KVM_EXIT_IO;
8075 vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT;
8076 vcpu->run->io.size = size;
8077 vcpu->run->io.data_offset = KVM_PIO_PAGE_OFFSET * PAGE_SIZE;
8078 vcpu->run->io.count = count;
8079 vcpu->run->io.port = port;
8080 return 0;
8081 }
8082
emulator_pio_in(struct kvm_vcpu * vcpu,int size,unsigned short port,void * val,unsigned int count)8083 static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
8084 unsigned short port, void *val, unsigned int count)
8085 {
8086 int r = emulator_pio_in_out(vcpu, size, port, val, count, true);
8087 if (r)
8088 trace_kvm_pio(KVM_PIO_IN, port, size, count, val);
8089
8090 return r;
8091 }
8092
complete_emulator_pio_in(struct kvm_vcpu * vcpu,void * val)8093 static void complete_emulator_pio_in(struct kvm_vcpu *vcpu, void *val)
8094 {
8095 int size = vcpu->arch.pio.size;
8096 unsigned int count = vcpu->arch.pio.count;
8097 memcpy(val, vcpu->arch.pio_data, size * count);
8098 trace_kvm_pio(KVM_PIO_IN, vcpu->arch.pio.port, size, count, vcpu->arch.pio_data);
8099 vcpu->arch.pio.count = 0;
8100 }
8101
emulator_pio_in_emulated(struct x86_emulate_ctxt * ctxt,int size,unsigned short port,void * val,unsigned int count)8102 static int emulator_pio_in_emulated(struct x86_emulate_ctxt *ctxt,
8103 int size, unsigned short port, void *val,
8104 unsigned int count)
8105 {
8106 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8107 if (vcpu->arch.pio.count) {
8108 /*
8109 * Complete a previous iteration that required userspace I/O.
8110 * Note, @count isn't guaranteed to match pio.count as userspace
8111 * can modify ECX before rerunning the vCPU. Ignore any such
8112 * shenanigans as KVM doesn't support modifying the rep count,
8113 * and the emulator ensures @count doesn't overflow the buffer.
8114 */
8115 complete_emulator_pio_in(vcpu, val);
8116 return 1;
8117 }
8118
8119 return emulator_pio_in(vcpu, size, port, val, count);
8120 }
8121
emulator_pio_out(struct kvm_vcpu * vcpu,int size,unsigned short port,const void * val,unsigned int count)8122 static int emulator_pio_out(struct kvm_vcpu *vcpu, int size,
8123 unsigned short port, const void *val,
8124 unsigned int count)
8125 {
8126 trace_kvm_pio(KVM_PIO_OUT, port, size, count, val);
8127 return emulator_pio_in_out(vcpu, size, port, (void *)val, count, false);
8128 }
8129
emulator_pio_out_emulated(struct x86_emulate_ctxt * ctxt,int size,unsigned short port,const void * val,unsigned int count)8130 static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt,
8131 int size, unsigned short port,
8132 const void *val, unsigned int count)
8133 {
8134 return emulator_pio_out(emul_to_vcpu(ctxt), size, port, val, count);
8135 }
8136
get_segment_base(struct kvm_vcpu * vcpu,int seg)8137 static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg)
8138 {
8139 return kvm_x86_call(get_segment_base)(vcpu, seg);
8140 }
8141
emulator_invlpg(struct x86_emulate_ctxt * ctxt,ulong address)8142 static void emulator_invlpg(struct x86_emulate_ctxt *ctxt, ulong address)
8143 {
8144 kvm_mmu_invlpg(emul_to_vcpu(ctxt), address);
8145 }
8146
kvm_emulate_wbinvd_noskip(struct kvm_vcpu * vcpu)8147 static int kvm_emulate_wbinvd_noskip(struct kvm_vcpu *vcpu)
8148 {
8149 if (!need_emulate_wbinvd(vcpu))
8150 return X86EMUL_CONTINUE;
8151
8152 if (kvm_x86_call(has_wbinvd_exit)()) {
8153 int cpu = get_cpu();
8154
8155 cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask);
8156 wbinvd_on_cpus_mask(vcpu->arch.wbinvd_dirty_mask);
8157 put_cpu();
8158 cpumask_clear(vcpu->arch.wbinvd_dirty_mask);
8159 } else
8160 wbinvd();
8161 return X86EMUL_CONTINUE;
8162 }
8163
kvm_emulate_wbinvd(struct kvm_vcpu * vcpu)8164 int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu)
8165 {
8166 kvm_emulate_wbinvd_noskip(vcpu);
8167 return kvm_skip_emulated_instruction(vcpu);
8168 }
8169 EXPORT_SYMBOL_GPL(kvm_emulate_wbinvd);
8170
8171
8172
emulator_wbinvd(struct x86_emulate_ctxt * ctxt)8173 static void emulator_wbinvd(struct x86_emulate_ctxt *ctxt)
8174 {
8175 kvm_emulate_wbinvd_noskip(emul_to_vcpu(ctxt));
8176 }
8177
emulator_get_dr(struct x86_emulate_ctxt * ctxt,int dr)8178 static unsigned long emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr)
8179 {
8180 return kvm_get_dr(emul_to_vcpu(ctxt), dr);
8181 }
8182
emulator_set_dr(struct x86_emulate_ctxt * ctxt,int dr,unsigned long value)8183 static int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr,
8184 unsigned long value)
8185 {
8186
8187 return kvm_set_dr(emul_to_vcpu(ctxt), dr, value);
8188 }
8189
mk_cr_64(u64 curr_cr,u32 new_val)8190 static u64 mk_cr_64(u64 curr_cr, u32 new_val)
8191 {
8192 return (curr_cr & ~((1ULL << 32) - 1)) | new_val;
8193 }
8194
emulator_get_cr(struct x86_emulate_ctxt * ctxt,int cr)8195 static unsigned long emulator_get_cr(struct x86_emulate_ctxt *ctxt, int cr)
8196 {
8197 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8198 unsigned long value;
8199
8200 switch (cr) {
8201 case 0:
8202 value = kvm_read_cr0(vcpu);
8203 break;
8204 case 2:
8205 value = vcpu->arch.cr2;
8206 break;
8207 case 3:
8208 value = kvm_read_cr3(vcpu);
8209 break;
8210 case 4:
8211 value = kvm_read_cr4(vcpu);
8212 break;
8213 case 8:
8214 value = kvm_get_cr8(vcpu);
8215 break;
8216 default:
8217 kvm_err("%s: unexpected cr %u\n", __func__, cr);
8218 return 0;
8219 }
8220
8221 return value;
8222 }
8223
emulator_set_cr(struct x86_emulate_ctxt * ctxt,int cr,ulong val)8224 static int emulator_set_cr(struct x86_emulate_ctxt *ctxt, int cr, ulong val)
8225 {
8226 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8227 int res = 0;
8228
8229 switch (cr) {
8230 case 0:
8231 res = kvm_set_cr0(vcpu, mk_cr_64(kvm_read_cr0(vcpu), val));
8232 break;
8233 case 2:
8234 vcpu->arch.cr2 = val;
8235 break;
8236 case 3:
8237 res = kvm_set_cr3(vcpu, val);
8238 break;
8239 case 4:
8240 res = kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val));
8241 break;
8242 case 8:
8243 res = kvm_set_cr8(vcpu, val);
8244 break;
8245 default:
8246 kvm_err("%s: unexpected cr %u\n", __func__, cr);
8247 res = -1;
8248 }
8249
8250 return res;
8251 }
8252
emulator_get_cpl(struct x86_emulate_ctxt * ctxt)8253 static int emulator_get_cpl(struct x86_emulate_ctxt *ctxt)
8254 {
8255 return kvm_x86_call(get_cpl)(emul_to_vcpu(ctxt));
8256 }
8257
emulator_get_gdt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8258 static void emulator_get_gdt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8259 {
8260 kvm_x86_call(get_gdt)(emul_to_vcpu(ctxt), dt);
8261 }
8262
emulator_get_idt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8263 static void emulator_get_idt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8264 {
8265 kvm_x86_call(get_idt)(emul_to_vcpu(ctxt), dt);
8266 }
8267
emulator_set_gdt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8268 static void emulator_set_gdt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8269 {
8270 kvm_x86_call(set_gdt)(emul_to_vcpu(ctxt), dt);
8271 }
8272
emulator_set_idt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8273 static void emulator_set_idt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8274 {
8275 kvm_x86_call(set_idt)(emul_to_vcpu(ctxt), dt);
8276 }
8277
emulator_get_cached_segment_base(struct x86_emulate_ctxt * ctxt,int seg)8278 static unsigned long emulator_get_cached_segment_base(
8279 struct x86_emulate_ctxt *ctxt, int seg)
8280 {
8281 return get_segment_base(emul_to_vcpu(ctxt), seg);
8282 }
8283
emulator_get_segment(struct x86_emulate_ctxt * ctxt,u16 * selector,struct desc_struct * desc,u32 * base3,int seg)8284 static bool emulator_get_segment(struct x86_emulate_ctxt *ctxt, u16 *selector,
8285 struct desc_struct *desc, u32 *base3,
8286 int seg)
8287 {
8288 struct kvm_segment var;
8289
8290 kvm_get_segment(emul_to_vcpu(ctxt), &var, seg);
8291 *selector = var.selector;
8292
8293 if (var.unusable) {
8294 memset(desc, 0, sizeof(*desc));
8295 if (base3)
8296 *base3 = 0;
8297 return false;
8298 }
8299
8300 if (var.g)
8301 var.limit >>= 12;
8302 set_desc_limit(desc, var.limit);
8303 set_desc_base(desc, (unsigned long)var.base);
8304 #ifdef CONFIG_X86_64
8305 if (base3)
8306 *base3 = var.base >> 32;
8307 #endif
8308 desc->type = var.type;
8309 desc->s = var.s;
8310 desc->dpl = var.dpl;
8311 desc->p = var.present;
8312 desc->avl = var.avl;
8313 desc->l = var.l;
8314 desc->d = var.db;
8315 desc->g = var.g;
8316
8317 return true;
8318 }
8319
emulator_set_segment(struct x86_emulate_ctxt * ctxt,u16 selector,struct desc_struct * desc,u32 base3,int seg)8320 static void emulator_set_segment(struct x86_emulate_ctxt *ctxt, u16 selector,
8321 struct desc_struct *desc, u32 base3,
8322 int seg)
8323 {
8324 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8325 struct kvm_segment var;
8326
8327 var.selector = selector;
8328 var.base = get_desc_base(desc);
8329 #ifdef CONFIG_X86_64
8330 var.base |= ((u64)base3) << 32;
8331 #endif
8332 var.limit = get_desc_limit(desc);
8333 if (desc->g)
8334 var.limit = (var.limit << 12) | 0xfff;
8335 var.type = desc->type;
8336 var.dpl = desc->dpl;
8337 var.db = desc->d;
8338 var.s = desc->s;
8339 var.l = desc->l;
8340 var.g = desc->g;
8341 var.avl = desc->avl;
8342 var.present = desc->p;
8343 var.unusable = !var.present;
8344 var.padding = 0;
8345
8346 kvm_set_segment(vcpu, &var, seg);
8347 return;
8348 }
8349
emulator_get_msr_with_filter(struct x86_emulate_ctxt * ctxt,u32 msr_index,u64 * pdata)8350 static int emulator_get_msr_with_filter(struct x86_emulate_ctxt *ctxt,
8351 u32 msr_index, u64 *pdata)
8352 {
8353 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8354 int r;
8355
8356 r = kvm_get_msr_with_filter(vcpu, msr_index, pdata);
8357 if (r < 0)
8358 return X86EMUL_UNHANDLEABLE;
8359
8360 if (r) {
8361 if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_RDMSR, 0,
8362 complete_emulated_rdmsr, r))
8363 return X86EMUL_IO_NEEDED;
8364
8365 trace_kvm_msr_read_ex(msr_index);
8366 return X86EMUL_PROPAGATE_FAULT;
8367 }
8368
8369 trace_kvm_msr_read(msr_index, *pdata);
8370 return X86EMUL_CONTINUE;
8371 }
8372
emulator_set_msr_with_filter(struct x86_emulate_ctxt * ctxt,u32 msr_index,u64 data)8373 static int emulator_set_msr_with_filter(struct x86_emulate_ctxt *ctxt,
8374 u32 msr_index, u64 data)
8375 {
8376 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8377 int r;
8378
8379 r = kvm_set_msr_with_filter(vcpu, msr_index, data);
8380 if (r < 0)
8381 return X86EMUL_UNHANDLEABLE;
8382
8383 if (r) {
8384 if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_WRMSR, data,
8385 complete_emulated_msr_access, r))
8386 return X86EMUL_IO_NEEDED;
8387
8388 trace_kvm_msr_write_ex(msr_index, data);
8389 return X86EMUL_PROPAGATE_FAULT;
8390 }
8391
8392 trace_kvm_msr_write(msr_index, data);
8393 return X86EMUL_CONTINUE;
8394 }
8395
emulator_get_msr(struct x86_emulate_ctxt * ctxt,u32 msr_index,u64 * pdata)8396 static int emulator_get_msr(struct x86_emulate_ctxt *ctxt,
8397 u32 msr_index, u64 *pdata)
8398 {
8399 return kvm_get_msr(emul_to_vcpu(ctxt), msr_index, pdata);
8400 }
8401
emulator_check_rdpmc_early(struct x86_emulate_ctxt * ctxt,u32 pmc)8402 static int emulator_check_rdpmc_early(struct x86_emulate_ctxt *ctxt, u32 pmc)
8403 {
8404 return kvm_pmu_check_rdpmc_early(emul_to_vcpu(ctxt), pmc);
8405 }
8406
emulator_read_pmc(struct x86_emulate_ctxt * ctxt,u32 pmc,u64 * pdata)8407 static int emulator_read_pmc(struct x86_emulate_ctxt *ctxt,
8408 u32 pmc, u64 *pdata)
8409 {
8410 return kvm_pmu_rdpmc(emul_to_vcpu(ctxt), pmc, pdata);
8411 }
8412
emulator_halt(struct x86_emulate_ctxt * ctxt)8413 static void emulator_halt(struct x86_emulate_ctxt *ctxt)
8414 {
8415 emul_to_vcpu(ctxt)->arch.halt_request = 1;
8416 }
8417
emulator_intercept(struct x86_emulate_ctxt * ctxt,struct x86_instruction_info * info,enum x86_intercept_stage stage)8418 static int emulator_intercept(struct x86_emulate_ctxt *ctxt,
8419 struct x86_instruction_info *info,
8420 enum x86_intercept_stage stage)
8421 {
8422 return kvm_x86_call(check_intercept)(emul_to_vcpu(ctxt), info, stage,
8423 &ctxt->exception);
8424 }
8425
emulator_get_cpuid(struct x86_emulate_ctxt * ctxt,u32 * eax,u32 * ebx,u32 * ecx,u32 * edx,bool exact_only)8426 static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt,
8427 u32 *eax, u32 *ebx, u32 *ecx, u32 *edx,
8428 bool exact_only)
8429 {
8430 return kvm_cpuid(emul_to_vcpu(ctxt), eax, ebx, ecx, edx, exact_only);
8431 }
8432
emulator_guest_has_movbe(struct x86_emulate_ctxt * ctxt)8433 static bool emulator_guest_has_movbe(struct x86_emulate_ctxt *ctxt)
8434 {
8435 return guest_cpu_cap_has(emul_to_vcpu(ctxt), X86_FEATURE_MOVBE);
8436 }
8437
emulator_guest_has_fxsr(struct x86_emulate_ctxt * ctxt)8438 static bool emulator_guest_has_fxsr(struct x86_emulate_ctxt *ctxt)
8439 {
8440 return guest_cpu_cap_has(emul_to_vcpu(ctxt), X86_FEATURE_FXSR);
8441 }
8442
emulator_guest_has_rdpid(struct x86_emulate_ctxt * ctxt)8443 static bool emulator_guest_has_rdpid(struct x86_emulate_ctxt *ctxt)
8444 {
8445 return guest_cpu_cap_has(emul_to_vcpu(ctxt), X86_FEATURE_RDPID);
8446 }
8447
emulator_guest_cpuid_is_intel_compatible(struct x86_emulate_ctxt * ctxt)8448 static bool emulator_guest_cpuid_is_intel_compatible(struct x86_emulate_ctxt *ctxt)
8449 {
8450 return guest_cpuid_is_intel_compatible(emul_to_vcpu(ctxt));
8451 }
8452
emulator_read_gpr(struct x86_emulate_ctxt * ctxt,unsigned reg)8453 static ulong emulator_read_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg)
8454 {
8455 return kvm_register_read_raw(emul_to_vcpu(ctxt), reg);
8456 }
8457
emulator_write_gpr(struct x86_emulate_ctxt * ctxt,unsigned reg,ulong val)8458 static void emulator_write_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg, ulong val)
8459 {
8460 kvm_register_write_raw(emul_to_vcpu(ctxt), reg, val);
8461 }
8462
emulator_set_nmi_mask(struct x86_emulate_ctxt * ctxt,bool masked)8463 static void emulator_set_nmi_mask(struct x86_emulate_ctxt *ctxt, bool masked)
8464 {
8465 kvm_x86_call(set_nmi_mask)(emul_to_vcpu(ctxt), masked);
8466 }
8467
emulator_is_smm(struct x86_emulate_ctxt * ctxt)8468 static bool emulator_is_smm(struct x86_emulate_ctxt *ctxt)
8469 {
8470 return is_smm(emul_to_vcpu(ctxt));
8471 }
8472
emulator_is_guest_mode(struct x86_emulate_ctxt * ctxt)8473 static bool emulator_is_guest_mode(struct x86_emulate_ctxt *ctxt)
8474 {
8475 return is_guest_mode(emul_to_vcpu(ctxt));
8476 }
8477
8478 #ifndef CONFIG_KVM_SMM
emulator_leave_smm(struct x86_emulate_ctxt * ctxt)8479 static int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
8480 {
8481 WARN_ON_ONCE(1);
8482 return X86EMUL_UNHANDLEABLE;
8483 }
8484 #endif
8485
emulator_triple_fault(struct x86_emulate_ctxt * ctxt)8486 static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt)
8487 {
8488 kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt));
8489 }
8490
emulator_set_xcr(struct x86_emulate_ctxt * ctxt,u32 index,u64 xcr)8491 static int emulator_set_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr)
8492 {
8493 return __kvm_set_xcr(emul_to_vcpu(ctxt), index, xcr);
8494 }
8495
emulator_vm_bugged(struct x86_emulate_ctxt * ctxt)8496 static void emulator_vm_bugged(struct x86_emulate_ctxt *ctxt)
8497 {
8498 struct kvm *kvm = emul_to_vcpu(ctxt)->kvm;
8499
8500 if (!kvm->vm_bugged)
8501 kvm_vm_bugged(kvm);
8502 }
8503
emulator_get_untagged_addr(struct x86_emulate_ctxt * ctxt,gva_t addr,unsigned int flags)8504 static gva_t emulator_get_untagged_addr(struct x86_emulate_ctxt *ctxt,
8505 gva_t addr, unsigned int flags)
8506 {
8507 if (!kvm_x86_ops.get_untagged_addr)
8508 return addr;
8509
8510 return kvm_x86_call(get_untagged_addr)(emul_to_vcpu(ctxt),
8511 addr, flags);
8512 }
8513
emulator_is_canonical_addr(struct x86_emulate_ctxt * ctxt,gva_t addr,unsigned int flags)8514 static bool emulator_is_canonical_addr(struct x86_emulate_ctxt *ctxt,
8515 gva_t addr, unsigned int flags)
8516 {
8517 return !is_noncanonical_address(addr, emul_to_vcpu(ctxt), flags);
8518 }
8519
8520 static const struct x86_emulate_ops emulate_ops = {
8521 .vm_bugged = emulator_vm_bugged,
8522 .read_gpr = emulator_read_gpr,
8523 .write_gpr = emulator_write_gpr,
8524 .read_std = emulator_read_std,
8525 .write_std = emulator_write_std,
8526 .fetch = kvm_fetch_guest_virt,
8527 .read_emulated = emulator_read_emulated,
8528 .write_emulated = emulator_write_emulated,
8529 .cmpxchg_emulated = emulator_cmpxchg_emulated,
8530 .invlpg = emulator_invlpg,
8531 .pio_in_emulated = emulator_pio_in_emulated,
8532 .pio_out_emulated = emulator_pio_out_emulated,
8533 .get_segment = emulator_get_segment,
8534 .set_segment = emulator_set_segment,
8535 .get_cached_segment_base = emulator_get_cached_segment_base,
8536 .get_gdt = emulator_get_gdt,
8537 .get_idt = emulator_get_idt,
8538 .set_gdt = emulator_set_gdt,
8539 .set_idt = emulator_set_idt,
8540 .get_cr = emulator_get_cr,
8541 .set_cr = emulator_set_cr,
8542 .cpl = emulator_get_cpl,
8543 .get_dr = emulator_get_dr,
8544 .set_dr = emulator_set_dr,
8545 .set_msr_with_filter = emulator_set_msr_with_filter,
8546 .get_msr_with_filter = emulator_get_msr_with_filter,
8547 .get_msr = emulator_get_msr,
8548 .check_rdpmc_early = emulator_check_rdpmc_early,
8549 .read_pmc = emulator_read_pmc,
8550 .halt = emulator_halt,
8551 .wbinvd = emulator_wbinvd,
8552 .fix_hypercall = emulator_fix_hypercall,
8553 .intercept = emulator_intercept,
8554 .get_cpuid = emulator_get_cpuid,
8555 .guest_has_movbe = emulator_guest_has_movbe,
8556 .guest_has_fxsr = emulator_guest_has_fxsr,
8557 .guest_has_rdpid = emulator_guest_has_rdpid,
8558 .guest_cpuid_is_intel_compatible = emulator_guest_cpuid_is_intel_compatible,
8559 .set_nmi_mask = emulator_set_nmi_mask,
8560 .is_smm = emulator_is_smm,
8561 .is_guest_mode = emulator_is_guest_mode,
8562 .leave_smm = emulator_leave_smm,
8563 .triple_fault = emulator_triple_fault,
8564 .set_xcr = emulator_set_xcr,
8565 .get_untagged_addr = emulator_get_untagged_addr,
8566 .is_canonical_addr = emulator_is_canonical_addr,
8567 };
8568
toggle_interruptibility(struct kvm_vcpu * vcpu,u32 mask)8569 static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask)
8570 {
8571 u32 int_shadow = kvm_x86_call(get_interrupt_shadow)(vcpu);
8572 /*
8573 * an sti; sti; sequence only disable interrupts for the first
8574 * instruction. So, if the last instruction, be it emulated or
8575 * not, left the system with the INT_STI flag enabled, it
8576 * means that the last instruction is an sti. We should not
8577 * leave the flag on in this case. The same goes for mov ss
8578 */
8579 if (int_shadow & mask)
8580 mask = 0;
8581 if (unlikely(int_shadow || mask)) {
8582 kvm_x86_call(set_interrupt_shadow)(vcpu, mask);
8583 if (!mask)
8584 kvm_make_request(KVM_REQ_EVENT, vcpu);
8585 }
8586 }
8587
inject_emulated_exception(struct kvm_vcpu * vcpu)8588 static void inject_emulated_exception(struct kvm_vcpu *vcpu)
8589 {
8590 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8591
8592 if (ctxt->exception.vector == PF_VECTOR)
8593 kvm_inject_emulated_page_fault(vcpu, &ctxt->exception);
8594 else if (ctxt->exception.error_code_valid)
8595 kvm_queue_exception_e(vcpu, ctxt->exception.vector,
8596 ctxt->exception.error_code);
8597 else
8598 kvm_queue_exception(vcpu, ctxt->exception.vector);
8599 }
8600
alloc_emulate_ctxt(struct kvm_vcpu * vcpu)8601 static struct x86_emulate_ctxt *alloc_emulate_ctxt(struct kvm_vcpu *vcpu)
8602 {
8603 struct x86_emulate_ctxt *ctxt;
8604
8605 ctxt = kmem_cache_zalloc(x86_emulator_cache, GFP_KERNEL_ACCOUNT);
8606 if (!ctxt) {
8607 pr_err("failed to allocate vcpu's emulator\n");
8608 return NULL;
8609 }
8610
8611 ctxt->vcpu = vcpu;
8612 ctxt->ops = &emulate_ops;
8613 vcpu->arch.emulate_ctxt = ctxt;
8614
8615 return ctxt;
8616 }
8617
init_emulate_ctxt(struct kvm_vcpu * vcpu)8618 static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
8619 {
8620 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8621 int cs_db, cs_l;
8622
8623 kvm_x86_call(get_cs_db_l_bits)(vcpu, &cs_db, &cs_l);
8624
8625 ctxt->gpa_available = false;
8626 ctxt->eflags = kvm_get_rflags(vcpu);
8627 ctxt->tf = (ctxt->eflags & X86_EFLAGS_TF) != 0;
8628
8629 ctxt->eip = kvm_rip_read(vcpu);
8630 ctxt->mode = (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
8631 (ctxt->eflags & X86_EFLAGS_VM) ? X86EMUL_MODE_VM86 :
8632 (cs_l && is_long_mode(vcpu)) ? X86EMUL_MODE_PROT64 :
8633 cs_db ? X86EMUL_MODE_PROT32 :
8634 X86EMUL_MODE_PROT16;
8635 ctxt->interruptibility = 0;
8636 ctxt->have_exception = false;
8637 ctxt->exception.vector = -1;
8638 ctxt->perm_ok = false;
8639
8640 init_decode_cache(ctxt);
8641 vcpu->arch.emulate_regs_need_sync_from_vcpu = false;
8642 }
8643
kvm_inject_realmode_interrupt(struct kvm_vcpu * vcpu,int irq,int inc_eip)8644 void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip)
8645 {
8646 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8647 int ret;
8648
8649 init_emulate_ctxt(vcpu);
8650
8651 ctxt->op_bytes = 2;
8652 ctxt->ad_bytes = 2;
8653 ctxt->_eip = ctxt->eip + inc_eip;
8654 ret = emulate_int_real(ctxt, irq);
8655
8656 if (ret != X86EMUL_CONTINUE) {
8657 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
8658 } else {
8659 ctxt->eip = ctxt->_eip;
8660 kvm_rip_write(vcpu, ctxt->eip);
8661 kvm_set_rflags(vcpu, ctxt->eflags);
8662 }
8663 }
8664 EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);
8665
prepare_emulation_failure_exit(struct kvm_vcpu * vcpu,u64 * data,u8 ndata,u8 * insn_bytes,u8 insn_size)8666 static void prepare_emulation_failure_exit(struct kvm_vcpu *vcpu, u64 *data,
8667 u8 ndata, u8 *insn_bytes, u8 insn_size)
8668 {
8669 struct kvm_run *run = vcpu->run;
8670 u64 info[5];
8671 u8 info_start;
8672
8673 /*
8674 * Zero the whole array used to retrieve the exit info, as casting to
8675 * u32 for select entries will leave some chunks uninitialized.
8676 */
8677 memset(&info, 0, sizeof(info));
8678
8679 kvm_x86_call(get_exit_info)(vcpu, (u32 *)&info[0], &info[1], &info[2],
8680 (u32 *)&info[3], (u32 *)&info[4]);
8681
8682 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
8683 run->emulation_failure.suberror = KVM_INTERNAL_ERROR_EMULATION;
8684
8685 /*
8686 * There's currently space for 13 entries, but 5 are used for the exit
8687 * reason and info. Restrict to 4 to reduce the maintenance burden
8688 * when expanding kvm_run.emulation_failure in the future.
8689 */
8690 if (WARN_ON_ONCE(ndata > 4))
8691 ndata = 4;
8692
8693 /* Always include the flags as a 'data' entry. */
8694 info_start = 1;
8695 run->emulation_failure.flags = 0;
8696
8697 if (insn_size) {
8698 BUILD_BUG_ON((sizeof(run->emulation_failure.insn_size) +
8699 sizeof(run->emulation_failure.insn_bytes) != 16));
8700 info_start += 2;
8701 run->emulation_failure.flags |=
8702 KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES;
8703 run->emulation_failure.insn_size = insn_size;
8704 memset(run->emulation_failure.insn_bytes, 0x90,
8705 sizeof(run->emulation_failure.insn_bytes));
8706 memcpy(run->emulation_failure.insn_bytes, insn_bytes, insn_size);
8707 }
8708
8709 memcpy(&run->internal.data[info_start], info, sizeof(info));
8710 memcpy(&run->internal.data[info_start + ARRAY_SIZE(info)], data,
8711 ndata * sizeof(data[0]));
8712
8713 run->emulation_failure.ndata = info_start + ARRAY_SIZE(info) + ndata;
8714 }
8715
prepare_emulation_ctxt_failure_exit(struct kvm_vcpu * vcpu)8716 static void prepare_emulation_ctxt_failure_exit(struct kvm_vcpu *vcpu)
8717 {
8718 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8719
8720 prepare_emulation_failure_exit(vcpu, NULL, 0, ctxt->fetch.data,
8721 ctxt->fetch.end - ctxt->fetch.data);
8722 }
8723
__kvm_prepare_emulation_failure_exit(struct kvm_vcpu * vcpu,u64 * data,u8 ndata)8724 void __kvm_prepare_emulation_failure_exit(struct kvm_vcpu *vcpu, u64 *data,
8725 u8 ndata)
8726 {
8727 prepare_emulation_failure_exit(vcpu, data, ndata, NULL, 0);
8728 }
8729 EXPORT_SYMBOL_GPL(__kvm_prepare_emulation_failure_exit);
8730
kvm_prepare_emulation_failure_exit(struct kvm_vcpu * vcpu)8731 void kvm_prepare_emulation_failure_exit(struct kvm_vcpu *vcpu)
8732 {
8733 __kvm_prepare_emulation_failure_exit(vcpu, NULL, 0);
8734 }
8735 EXPORT_SYMBOL_GPL(kvm_prepare_emulation_failure_exit);
8736
kvm_prepare_event_vectoring_exit(struct kvm_vcpu * vcpu,gpa_t gpa)8737 void kvm_prepare_event_vectoring_exit(struct kvm_vcpu *vcpu, gpa_t gpa)
8738 {
8739 u32 reason, intr_info, error_code;
8740 struct kvm_run *run = vcpu->run;
8741 u64 info1, info2;
8742 int ndata = 0;
8743
8744 kvm_x86_call(get_exit_info)(vcpu, &reason, &info1, &info2,
8745 &intr_info, &error_code);
8746
8747 run->internal.data[ndata++] = info2;
8748 run->internal.data[ndata++] = reason;
8749 run->internal.data[ndata++] = info1;
8750 run->internal.data[ndata++] = gpa;
8751 run->internal.data[ndata++] = vcpu->arch.last_vmentry_cpu;
8752
8753 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
8754 run->internal.suberror = KVM_INTERNAL_ERROR_DELIVERY_EV;
8755 run->internal.ndata = ndata;
8756 }
8757 EXPORT_SYMBOL_GPL(kvm_prepare_event_vectoring_exit);
8758
handle_emulation_failure(struct kvm_vcpu * vcpu,int emulation_type)8759 static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type)
8760 {
8761 struct kvm *kvm = vcpu->kvm;
8762
8763 ++vcpu->stat.insn_emulation_fail;
8764 trace_kvm_emulate_insn_failed(vcpu);
8765
8766 if (emulation_type & EMULTYPE_VMWARE_GP) {
8767 kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
8768 return 1;
8769 }
8770
8771 if (kvm->arch.exit_on_emulation_error ||
8772 (emulation_type & EMULTYPE_SKIP)) {
8773 prepare_emulation_ctxt_failure_exit(vcpu);
8774 return 0;
8775 }
8776
8777 kvm_queue_exception(vcpu, UD_VECTOR);
8778
8779 if (!is_guest_mode(vcpu) && kvm_x86_call(get_cpl)(vcpu) == 0) {
8780 prepare_emulation_ctxt_failure_exit(vcpu);
8781 return 0;
8782 }
8783
8784 return 1;
8785 }
8786
kvm_unprotect_and_retry_on_failure(struct kvm_vcpu * vcpu,gpa_t cr2_or_gpa,int emulation_type)8787 static bool kvm_unprotect_and_retry_on_failure(struct kvm_vcpu *vcpu,
8788 gpa_t cr2_or_gpa,
8789 int emulation_type)
8790 {
8791 if (!(emulation_type & EMULTYPE_ALLOW_RETRY_PF))
8792 return false;
8793
8794 /*
8795 * If the failed instruction faulted on an access to page tables that
8796 * are used to translate any part of the instruction, KVM can't resolve
8797 * the issue by unprotecting the gfn, as zapping the shadow page will
8798 * result in the instruction taking a !PRESENT page fault and thus put
8799 * the vCPU into an infinite loop of page faults. E.g. KVM will create
8800 * a SPTE and write-protect the gfn to resolve the !PRESENT fault, and
8801 * then zap the SPTE to unprotect the gfn, and then do it all over
8802 * again. Report the error to userspace.
8803 */
8804 if (emulation_type & EMULTYPE_WRITE_PF_TO_SP)
8805 return false;
8806
8807 /*
8808 * If emulation may have been triggered by a write to a shadowed page
8809 * table, unprotect the gfn (zap any relevant SPTEs) and re-enter the
8810 * guest to let the CPU re-execute the instruction in the hope that the
8811 * CPU can cleanly execute the instruction that KVM failed to emulate.
8812 */
8813 __kvm_mmu_unprotect_gfn_and_retry(vcpu, cr2_or_gpa, true);
8814
8815 /*
8816 * Retry even if _this_ vCPU didn't unprotect the gfn, as it's possible
8817 * all SPTEs were already zapped by a different task. The alternative
8818 * is to report the error to userspace and likely terminate the guest,
8819 * and the last_retry_{eip,addr} checks will prevent retrying the page
8820 * fault indefinitely, i.e. there's nothing to lose by retrying.
8821 */
8822 return true;
8823 }
8824
8825 static int complete_emulated_mmio(struct kvm_vcpu *vcpu);
8826 static int complete_emulated_pio(struct kvm_vcpu *vcpu);
8827
kvm_vcpu_check_hw_bp(unsigned long addr,u32 type,u32 dr7,unsigned long * db)8828 static int kvm_vcpu_check_hw_bp(unsigned long addr, u32 type, u32 dr7,
8829 unsigned long *db)
8830 {
8831 u32 dr6 = 0;
8832 int i;
8833 u32 enable, rwlen;
8834
8835 enable = dr7;
8836 rwlen = dr7 >> 16;
8837 for (i = 0; i < 4; i++, enable >>= 2, rwlen >>= 4)
8838 if ((enable & 3) && (rwlen & 15) == type && db[i] == addr)
8839 dr6 |= (1 << i);
8840 return dr6;
8841 }
8842
kvm_vcpu_do_singlestep(struct kvm_vcpu * vcpu)8843 static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu)
8844 {
8845 struct kvm_run *kvm_run = vcpu->run;
8846
8847 if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
8848 kvm_run->debug.arch.dr6 = DR6_BS | DR6_ACTIVE_LOW;
8849 kvm_run->debug.arch.pc = kvm_get_linear_rip(vcpu);
8850 kvm_run->debug.arch.exception = DB_VECTOR;
8851 kvm_run->exit_reason = KVM_EXIT_DEBUG;
8852 return 0;
8853 }
8854 kvm_queue_exception_p(vcpu, DB_VECTOR, DR6_BS);
8855 return 1;
8856 }
8857
kvm_skip_emulated_instruction(struct kvm_vcpu * vcpu)8858 int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu)
8859 {
8860 unsigned long rflags = kvm_x86_call(get_rflags)(vcpu);
8861 int r;
8862
8863 r = kvm_x86_call(skip_emulated_instruction)(vcpu);
8864 if (unlikely(!r))
8865 return 0;
8866
8867 kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED);
8868
8869 /*
8870 * rflags is the old, "raw" value of the flags. The new value has
8871 * not been saved yet.
8872 *
8873 * This is correct even for TF set by the guest, because "the
8874 * processor will not generate this exception after the instruction
8875 * that sets the TF flag".
8876 */
8877 if (unlikely(rflags & X86_EFLAGS_TF))
8878 r = kvm_vcpu_do_singlestep(vcpu);
8879 return r;
8880 }
8881 EXPORT_SYMBOL_GPL(kvm_skip_emulated_instruction);
8882
kvm_is_code_breakpoint_inhibited(struct kvm_vcpu * vcpu)8883 static bool kvm_is_code_breakpoint_inhibited(struct kvm_vcpu *vcpu)
8884 {
8885 if (kvm_get_rflags(vcpu) & X86_EFLAGS_RF)
8886 return true;
8887
8888 /*
8889 * Intel compatible CPUs inhibit code #DBs when MOV/POP SS blocking is
8890 * active, but AMD compatible CPUs do not.
8891 */
8892 if (!guest_cpuid_is_intel_compatible(vcpu))
8893 return false;
8894
8895 return kvm_x86_call(get_interrupt_shadow)(vcpu) & KVM_X86_SHADOW_INT_MOV_SS;
8896 }
8897
kvm_vcpu_check_code_breakpoint(struct kvm_vcpu * vcpu,int emulation_type,int * r)8898 static bool kvm_vcpu_check_code_breakpoint(struct kvm_vcpu *vcpu,
8899 int emulation_type, int *r)
8900 {
8901 WARN_ON_ONCE(emulation_type & EMULTYPE_NO_DECODE);
8902
8903 /*
8904 * Do not check for code breakpoints if hardware has already done the
8905 * checks, as inferred from the emulation type. On NO_DECODE and SKIP,
8906 * the instruction has passed all exception checks, and all intercepted
8907 * exceptions that trigger emulation have lower priority than code
8908 * breakpoints, i.e. the fact that the intercepted exception occurred
8909 * means any code breakpoints have already been serviced.
8910 *
8911 * Note, KVM needs to check for code #DBs on EMULTYPE_TRAP_UD_FORCED as
8912 * hardware has checked the RIP of the magic prefix, but not the RIP of
8913 * the instruction being emulated. The intent of forced emulation is
8914 * to behave as if KVM intercepted the instruction without an exception
8915 * and without a prefix.
8916 */
8917 if (emulation_type & (EMULTYPE_NO_DECODE | EMULTYPE_SKIP |
8918 EMULTYPE_TRAP_UD | EMULTYPE_VMWARE_GP | EMULTYPE_PF))
8919 return false;
8920
8921 if (unlikely(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) &&
8922 (vcpu->arch.guest_debug_dr7 & DR7_BP_EN_MASK)) {
8923 struct kvm_run *kvm_run = vcpu->run;
8924 unsigned long eip = kvm_get_linear_rip(vcpu);
8925 u32 dr6 = kvm_vcpu_check_hw_bp(eip, 0,
8926 vcpu->arch.guest_debug_dr7,
8927 vcpu->arch.eff_db);
8928
8929 if (dr6 != 0) {
8930 kvm_run->debug.arch.dr6 = dr6 | DR6_ACTIVE_LOW;
8931 kvm_run->debug.arch.pc = eip;
8932 kvm_run->debug.arch.exception = DB_VECTOR;
8933 kvm_run->exit_reason = KVM_EXIT_DEBUG;
8934 *r = 0;
8935 return true;
8936 }
8937 }
8938
8939 if (unlikely(vcpu->arch.dr7 & DR7_BP_EN_MASK) &&
8940 !kvm_is_code_breakpoint_inhibited(vcpu)) {
8941 unsigned long eip = kvm_get_linear_rip(vcpu);
8942 u32 dr6 = kvm_vcpu_check_hw_bp(eip, 0,
8943 vcpu->arch.dr7,
8944 vcpu->arch.db);
8945
8946 if (dr6 != 0) {
8947 kvm_queue_exception_p(vcpu, DB_VECTOR, dr6);
8948 *r = 1;
8949 return true;
8950 }
8951 }
8952
8953 return false;
8954 }
8955
is_vmware_backdoor_opcode(struct x86_emulate_ctxt * ctxt)8956 static bool is_vmware_backdoor_opcode(struct x86_emulate_ctxt *ctxt)
8957 {
8958 switch (ctxt->opcode_len) {
8959 case 1:
8960 switch (ctxt->b) {
8961 case 0xe4: /* IN */
8962 case 0xe5:
8963 case 0xec:
8964 case 0xed:
8965 case 0xe6: /* OUT */
8966 case 0xe7:
8967 case 0xee:
8968 case 0xef:
8969 case 0x6c: /* INS */
8970 case 0x6d:
8971 case 0x6e: /* OUTS */
8972 case 0x6f:
8973 return true;
8974 }
8975 break;
8976 case 2:
8977 switch (ctxt->b) {
8978 case 0x33: /* RDPMC */
8979 return true;
8980 }
8981 break;
8982 }
8983
8984 return false;
8985 }
8986
8987 /*
8988 * Decode an instruction for emulation. The caller is responsible for handling
8989 * code breakpoints. Note, manually detecting code breakpoints is unnecessary
8990 * (and wrong) when emulating on an intercepted fault-like exception[*], as
8991 * code breakpoints have higher priority and thus have already been done by
8992 * hardware.
8993 *
8994 * [*] Except #MC, which is higher priority, but KVM should never emulate in
8995 * response to a machine check.
8996 */
x86_decode_emulated_instruction(struct kvm_vcpu * vcpu,int emulation_type,void * insn,int insn_len)8997 int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
8998 void *insn, int insn_len)
8999 {
9000 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
9001 int r;
9002
9003 init_emulate_ctxt(vcpu);
9004
9005 r = x86_decode_insn(ctxt, insn, insn_len, emulation_type);
9006
9007 trace_kvm_emulate_insn_start(vcpu);
9008 ++vcpu->stat.insn_emulation;
9009
9010 return r;
9011 }
9012 EXPORT_SYMBOL_GPL(x86_decode_emulated_instruction);
9013
x86_emulate_instruction(struct kvm_vcpu * vcpu,gpa_t cr2_or_gpa,int emulation_type,void * insn,int insn_len)9014 int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
9015 int emulation_type, void *insn, int insn_len)
9016 {
9017 int r;
9018 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
9019 bool writeback = true;
9020
9021 if ((emulation_type & EMULTYPE_ALLOW_RETRY_PF) &&
9022 (WARN_ON_ONCE(is_guest_mode(vcpu)) ||
9023 WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF))))
9024 emulation_type &= ~EMULTYPE_ALLOW_RETRY_PF;
9025
9026 r = kvm_check_emulate_insn(vcpu, emulation_type, insn, insn_len);
9027 if (r != X86EMUL_CONTINUE) {
9028 if (r == X86EMUL_RETRY_INSTR || r == X86EMUL_PROPAGATE_FAULT)
9029 return 1;
9030
9031 if (kvm_unprotect_and_retry_on_failure(vcpu, cr2_or_gpa,
9032 emulation_type))
9033 return 1;
9034
9035 if (r == X86EMUL_UNHANDLEABLE_VECTORING) {
9036 kvm_prepare_event_vectoring_exit(vcpu, cr2_or_gpa);
9037 return 0;
9038 }
9039
9040 WARN_ON_ONCE(r != X86EMUL_UNHANDLEABLE);
9041 return handle_emulation_failure(vcpu, emulation_type);
9042 }
9043
9044 vcpu->arch.l1tf_flush_l1d = true;
9045
9046 if (!(emulation_type & EMULTYPE_NO_DECODE)) {
9047 kvm_clear_exception_queue(vcpu);
9048
9049 /*
9050 * Return immediately if RIP hits a code breakpoint, such #DBs
9051 * are fault-like and are higher priority than any faults on
9052 * the code fetch itself.
9053 */
9054 if (kvm_vcpu_check_code_breakpoint(vcpu, emulation_type, &r))
9055 return r;
9056
9057 r = x86_decode_emulated_instruction(vcpu, emulation_type,
9058 insn, insn_len);
9059 if (r != EMULATION_OK) {
9060 if ((emulation_type & EMULTYPE_TRAP_UD) ||
9061 (emulation_type & EMULTYPE_TRAP_UD_FORCED)) {
9062 kvm_queue_exception(vcpu, UD_VECTOR);
9063 return 1;
9064 }
9065 if (kvm_unprotect_and_retry_on_failure(vcpu, cr2_or_gpa,
9066 emulation_type))
9067 return 1;
9068
9069 if (ctxt->have_exception &&
9070 !(emulation_type & EMULTYPE_SKIP)) {
9071 /*
9072 * #UD should result in just EMULATION_FAILED, and trap-like
9073 * exception should not be encountered during decode.
9074 */
9075 WARN_ON_ONCE(ctxt->exception.vector == UD_VECTOR ||
9076 exception_type(ctxt->exception.vector) == EXCPT_TRAP);
9077 inject_emulated_exception(vcpu);
9078 return 1;
9079 }
9080 return handle_emulation_failure(vcpu, emulation_type);
9081 }
9082 }
9083
9084 if ((emulation_type & EMULTYPE_VMWARE_GP) &&
9085 !is_vmware_backdoor_opcode(ctxt)) {
9086 kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
9087 return 1;
9088 }
9089
9090 /*
9091 * EMULTYPE_SKIP without EMULTYPE_COMPLETE_USER_EXIT is intended for
9092 * use *only* by vendor callbacks for kvm_skip_emulated_instruction().
9093 * The caller is responsible for updating interruptibility state and
9094 * injecting single-step #DBs.
9095 */
9096 if (emulation_type & EMULTYPE_SKIP) {
9097 if (ctxt->mode != X86EMUL_MODE_PROT64)
9098 ctxt->eip = (u32)ctxt->_eip;
9099 else
9100 ctxt->eip = ctxt->_eip;
9101
9102 if (emulation_type & EMULTYPE_COMPLETE_USER_EXIT) {
9103 r = 1;
9104 goto writeback;
9105 }
9106
9107 kvm_rip_write(vcpu, ctxt->eip);
9108 if (ctxt->eflags & X86_EFLAGS_RF)
9109 kvm_set_rflags(vcpu, ctxt->eflags & ~X86_EFLAGS_RF);
9110 return 1;
9111 }
9112
9113 /*
9114 * If emulation was caused by a write-protection #PF on a non-page_table
9115 * writing instruction, try to unprotect the gfn, i.e. zap shadow pages,
9116 * and retry the instruction, as the vCPU is likely no longer using the
9117 * gfn as a page table.
9118 */
9119 if ((emulation_type & EMULTYPE_ALLOW_RETRY_PF) &&
9120 !x86_page_table_writing_insn(ctxt) &&
9121 kvm_mmu_unprotect_gfn_and_retry(vcpu, cr2_or_gpa))
9122 return 1;
9123
9124 /* this is needed for vmware backdoor interface to work since it
9125 changes registers values during IO operation */
9126 if (vcpu->arch.emulate_regs_need_sync_from_vcpu) {
9127 vcpu->arch.emulate_regs_need_sync_from_vcpu = false;
9128 emulator_invalidate_register_cache(ctxt);
9129 }
9130
9131 restart:
9132 if (emulation_type & EMULTYPE_PF) {
9133 /* Save the faulting GPA (cr2) in the address field */
9134 ctxt->exception.address = cr2_or_gpa;
9135
9136 /* With shadow page tables, cr2 contains a GVA or nGPA. */
9137 if (vcpu->arch.mmu->root_role.direct) {
9138 ctxt->gpa_available = true;
9139 ctxt->gpa_val = cr2_or_gpa;
9140 }
9141 } else {
9142 /* Sanitize the address out of an abundance of paranoia. */
9143 ctxt->exception.address = 0;
9144 }
9145
9146 r = x86_emulate_insn(ctxt);
9147
9148 if (r == EMULATION_INTERCEPTED)
9149 return 1;
9150
9151 if (r == EMULATION_FAILED) {
9152 if (kvm_unprotect_and_retry_on_failure(vcpu, cr2_or_gpa,
9153 emulation_type))
9154 return 1;
9155
9156 return handle_emulation_failure(vcpu, emulation_type);
9157 }
9158
9159 if (ctxt->have_exception) {
9160 WARN_ON_ONCE(vcpu->mmio_needed && !vcpu->mmio_is_write);
9161 vcpu->mmio_needed = false;
9162 r = 1;
9163 inject_emulated_exception(vcpu);
9164 } else if (vcpu->arch.pio.count) {
9165 if (!vcpu->arch.pio.in) {
9166 /* FIXME: return into emulator if single-stepping. */
9167 vcpu->arch.pio.count = 0;
9168 } else {
9169 writeback = false;
9170 vcpu->arch.complete_userspace_io = complete_emulated_pio;
9171 }
9172 r = 0;
9173 } else if (vcpu->mmio_needed) {
9174 ++vcpu->stat.mmio_exits;
9175
9176 if (!vcpu->mmio_is_write)
9177 writeback = false;
9178 r = 0;
9179 vcpu->arch.complete_userspace_io = complete_emulated_mmio;
9180 } else if (vcpu->arch.complete_userspace_io) {
9181 writeback = false;
9182 r = 0;
9183 } else if (r == EMULATION_RESTART)
9184 goto restart;
9185 else
9186 r = 1;
9187
9188 writeback:
9189 if (writeback) {
9190 unsigned long rflags = kvm_x86_call(get_rflags)(vcpu);
9191 toggle_interruptibility(vcpu, ctxt->interruptibility);
9192 vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
9193
9194 /*
9195 * Note, EXCPT_DB is assumed to be fault-like as the emulator
9196 * only supports code breakpoints and general detect #DB, both
9197 * of which are fault-like.
9198 */
9199 if (!ctxt->have_exception ||
9200 exception_type(ctxt->exception.vector) == EXCPT_TRAP) {
9201 kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED);
9202 if (ctxt->is_branch)
9203 kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED);
9204 kvm_rip_write(vcpu, ctxt->eip);
9205 if (r && (ctxt->tf || (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)))
9206 r = kvm_vcpu_do_singlestep(vcpu);
9207 kvm_x86_call(update_emulated_instruction)(vcpu);
9208 __kvm_set_rflags(vcpu, ctxt->eflags);
9209 }
9210
9211 /*
9212 * For STI, interrupts are shadowed; so KVM_REQ_EVENT will
9213 * do nothing, and it will be requested again as soon as
9214 * the shadow expires. But we still need to check here,
9215 * because POPF has no interrupt shadow.
9216 */
9217 if (unlikely((ctxt->eflags & ~rflags) & X86_EFLAGS_IF))
9218 kvm_make_request(KVM_REQ_EVENT, vcpu);
9219 } else
9220 vcpu->arch.emulate_regs_need_sync_to_vcpu = true;
9221
9222 return r;
9223 }
9224
kvm_emulate_instruction(struct kvm_vcpu * vcpu,int emulation_type)9225 int kvm_emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type)
9226 {
9227 return x86_emulate_instruction(vcpu, 0, emulation_type, NULL, 0);
9228 }
9229 EXPORT_SYMBOL_GPL(kvm_emulate_instruction);
9230
kvm_emulate_instruction_from_buffer(struct kvm_vcpu * vcpu,void * insn,int insn_len)9231 int kvm_emulate_instruction_from_buffer(struct kvm_vcpu *vcpu,
9232 void *insn, int insn_len)
9233 {
9234 return x86_emulate_instruction(vcpu, 0, 0, insn, insn_len);
9235 }
9236 EXPORT_SYMBOL_GPL(kvm_emulate_instruction_from_buffer);
9237
complete_fast_pio_out_port_0x7e(struct kvm_vcpu * vcpu)9238 static int complete_fast_pio_out_port_0x7e(struct kvm_vcpu *vcpu)
9239 {
9240 vcpu->arch.pio.count = 0;
9241 return 1;
9242 }
9243
complete_fast_pio_out(struct kvm_vcpu * vcpu)9244 static int complete_fast_pio_out(struct kvm_vcpu *vcpu)
9245 {
9246 vcpu->arch.pio.count = 0;
9247
9248 if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.cui_linear_rip)))
9249 return 1;
9250
9251 return kvm_skip_emulated_instruction(vcpu);
9252 }
9253
kvm_fast_pio_out(struct kvm_vcpu * vcpu,int size,unsigned short port)9254 static int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size,
9255 unsigned short port)
9256 {
9257 unsigned long val = kvm_rax_read(vcpu);
9258 int ret = emulator_pio_out(vcpu, size, port, &val, 1);
9259
9260 if (ret)
9261 return ret;
9262
9263 /*
9264 * Workaround userspace that relies on old KVM behavior of %rip being
9265 * incremented prior to exiting to userspace to handle "OUT 0x7e".
9266 */
9267 if (port == 0x7e &&
9268 kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_OUT_7E_INC_RIP)) {
9269 vcpu->arch.complete_userspace_io =
9270 complete_fast_pio_out_port_0x7e;
9271 kvm_skip_emulated_instruction(vcpu);
9272 } else {
9273 vcpu->arch.cui_linear_rip = kvm_get_linear_rip(vcpu);
9274 vcpu->arch.complete_userspace_io = complete_fast_pio_out;
9275 }
9276 return 0;
9277 }
9278
complete_fast_pio_in(struct kvm_vcpu * vcpu)9279 static int complete_fast_pio_in(struct kvm_vcpu *vcpu)
9280 {
9281 unsigned long val;
9282
9283 /* We should only ever be called with arch.pio.count equal to 1 */
9284 BUG_ON(vcpu->arch.pio.count != 1);
9285
9286 if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.cui_linear_rip))) {
9287 vcpu->arch.pio.count = 0;
9288 return 1;
9289 }
9290
9291 /* For size less than 4 we merge, else we zero extend */
9292 val = (vcpu->arch.pio.size < 4) ? kvm_rax_read(vcpu) : 0;
9293
9294 complete_emulator_pio_in(vcpu, &val);
9295 kvm_rax_write(vcpu, val);
9296
9297 return kvm_skip_emulated_instruction(vcpu);
9298 }
9299
kvm_fast_pio_in(struct kvm_vcpu * vcpu,int size,unsigned short port)9300 static int kvm_fast_pio_in(struct kvm_vcpu *vcpu, int size,
9301 unsigned short port)
9302 {
9303 unsigned long val;
9304 int ret;
9305
9306 /* For size less than 4 we merge, else we zero extend */
9307 val = (size < 4) ? kvm_rax_read(vcpu) : 0;
9308
9309 ret = emulator_pio_in(vcpu, size, port, &val, 1);
9310 if (ret) {
9311 kvm_rax_write(vcpu, val);
9312 return ret;
9313 }
9314
9315 vcpu->arch.cui_linear_rip = kvm_get_linear_rip(vcpu);
9316 vcpu->arch.complete_userspace_io = complete_fast_pio_in;
9317
9318 return 0;
9319 }
9320
kvm_fast_pio(struct kvm_vcpu * vcpu,int size,unsigned short port,int in)9321 int kvm_fast_pio(struct kvm_vcpu *vcpu, int size, unsigned short port, int in)
9322 {
9323 int ret;
9324
9325 if (in)
9326 ret = kvm_fast_pio_in(vcpu, size, port);
9327 else
9328 ret = kvm_fast_pio_out(vcpu, size, port);
9329 return ret && kvm_skip_emulated_instruction(vcpu);
9330 }
9331 EXPORT_SYMBOL_GPL(kvm_fast_pio);
9332
kvmclock_cpu_down_prep(unsigned int cpu)9333 static int kvmclock_cpu_down_prep(unsigned int cpu)
9334 {
9335 __this_cpu_write(cpu_tsc_khz, 0);
9336 return 0;
9337 }
9338
tsc_khz_changed(void * data)9339 static void tsc_khz_changed(void *data)
9340 {
9341 struct cpufreq_freqs *freq = data;
9342 unsigned long khz;
9343
9344 WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_CONSTANT_TSC));
9345
9346 if (data)
9347 khz = freq->new;
9348 else
9349 khz = cpufreq_quick_get(raw_smp_processor_id());
9350 if (!khz)
9351 khz = tsc_khz;
9352 __this_cpu_write(cpu_tsc_khz, khz);
9353 }
9354
9355 #ifdef CONFIG_X86_64
kvm_hyperv_tsc_notifier(void)9356 static void kvm_hyperv_tsc_notifier(void)
9357 {
9358 struct kvm *kvm;
9359 int cpu;
9360
9361 mutex_lock(&kvm_lock);
9362 list_for_each_entry(kvm, &vm_list, vm_list)
9363 kvm_make_mclock_inprogress_request(kvm);
9364
9365 /* no guest entries from this point */
9366 hyperv_stop_tsc_emulation();
9367
9368 /* TSC frequency always matches when on Hyper-V */
9369 if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9370 for_each_present_cpu(cpu)
9371 per_cpu(cpu_tsc_khz, cpu) = tsc_khz;
9372 }
9373 kvm_caps.max_guest_tsc_khz = tsc_khz;
9374
9375 list_for_each_entry(kvm, &vm_list, vm_list) {
9376 __kvm_start_pvclock_update(kvm);
9377 pvclock_update_vm_gtod_copy(kvm);
9378 kvm_end_pvclock_update(kvm);
9379 }
9380
9381 mutex_unlock(&kvm_lock);
9382 }
9383 #endif
9384
__kvmclock_cpufreq_notifier(struct cpufreq_freqs * freq,int cpu)9385 static void __kvmclock_cpufreq_notifier(struct cpufreq_freqs *freq, int cpu)
9386 {
9387 struct kvm *kvm;
9388 struct kvm_vcpu *vcpu;
9389 int send_ipi = 0;
9390 unsigned long i;
9391
9392 /*
9393 * We allow guests to temporarily run on slowing clocks,
9394 * provided we notify them after, or to run on accelerating
9395 * clocks, provided we notify them before. Thus time never
9396 * goes backwards.
9397 *
9398 * However, we have a problem. We can't atomically update
9399 * the frequency of a given CPU from this function; it is
9400 * merely a notifier, which can be called from any CPU.
9401 * Changing the TSC frequency at arbitrary points in time
9402 * requires a recomputation of local variables related to
9403 * the TSC for each VCPU. We must flag these local variables
9404 * to be updated and be sure the update takes place with the
9405 * new frequency before any guests proceed.
9406 *
9407 * Unfortunately, the combination of hotplug CPU and frequency
9408 * change creates an intractable locking scenario; the order
9409 * of when these callouts happen is undefined with respect to
9410 * CPU hotplug, and they can race with each other. As such,
9411 * merely setting per_cpu(cpu_tsc_khz) = X during a hotadd is
9412 * undefined; you can actually have a CPU frequency change take
9413 * place in between the computation of X and the setting of the
9414 * variable. To protect against this problem, all updates of
9415 * the per_cpu tsc_khz variable are done in an interrupt
9416 * protected IPI, and all callers wishing to update the value
9417 * must wait for a synchronous IPI to complete (which is trivial
9418 * if the caller is on the CPU already). This establishes the
9419 * necessary total order on variable updates.
9420 *
9421 * Note that because a guest time update may take place
9422 * anytime after the setting of the VCPU's request bit, the
9423 * correct TSC value must be set before the request. However,
9424 * to ensure the update actually makes it to any guest which
9425 * starts running in hardware virtualization between the set
9426 * and the acquisition of the spinlock, we must also ping the
9427 * CPU after setting the request bit.
9428 *
9429 */
9430
9431 smp_call_function_single(cpu, tsc_khz_changed, freq, 1);
9432
9433 mutex_lock(&kvm_lock);
9434 list_for_each_entry(kvm, &vm_list, vm_list) {
9435 kvm_for_each_vcpu(i, vcpu, kvm) {
9436 if (vcpu->cpu != cpu)
9437 continue;
9438 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
9439 if (vcpu->cpu != raw_smp_processor_id())
9440 send_ipi = 1;
9441 }
9442 }
9443 mutex_unlock(&kvm_lock);
9444
9445 if (freq->old < freq->new && send_ipi) {
9446 /*
9447 * We upscale the frequency. Must make the guest
9448 * doesn't see old kvmclock values while running with
9449 * the new frequency, otherwise we risk the guest sees
9450 * time go backwards.
9451 *
9452 * In case we update the frequency for another cpu
9453 * (which might be in guest context) send an interrupt
9454 * to kick the cpu out of guest context. Next time
9455 * guest context is entered kvmclock will be updated,
9456 * so the guest will not see stale values.
9457 */
9458 smp_call_function_single(cpu, tsc_khz_changed, freq, 1);
9459 }
9460 }
9461
kvmclock_cpufreq_notifier(struct notifier_block * nb,unsigned long val,void * data)9462 static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
9463 void *data)
9464 {
9465 struct cpufreq_freqs *freq = data;
9466 int cpu;
9467
9468 if (val == CPUFREQ_PRECHANGE && freq->old > freq->new)
9469 return 0;
9470 if (val == CPUFREQ_POSTCHANGE && freq->old < freq->new)
9471 return 0;
9472
9473 for_each_cpu(cpu, freq->policy->cpus)
9474 __kvmclock_cpufreq_notifier(freq, cpu);
9475
9476 return 0;
9477 }
9478
9479 static struct notifier_block kvmclock_cpufreq_notifier_block = {
9480 .notifier_call = kvmclock_cpufreq_notifier
9481 };
9482
kvmclock_cpu_online(unsigned int cpu)9483 static int kvmclock_cpu_online(unsigned int cpu)
9484 {
9485 tsc_khz_changed(NULL);
9486 return 0;
9487 }
9488
kvm_timer_init(void)9489 static void kvm_timer_init(void)
9490 {
9491 if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9492 max_tsc_khz = tsc_khz;
9493
9494 if (IS_ENABLED(CONFIG_CPU_FREQ)) {
9495 struct cpufreq_policy *policy;
9496 int cpu;
9497
9498 cpu = get_cpu();
9499 policy = cpufreq_cpu_get(cpu);
9500 if (policy) {
9501 if (policy->cpuinfo.max_freq)
9502 max_tsc_khz = policy->cpuinfo.max_freq;
9503 cpufreq_cpu_put(policy);
9504 }
9505 put_cpu();
9506 }
9507 cpufreq_register_notifier(&kvmclock_cpufreq_notifier_block,
9508 CPUFREQ_TRANSITION_NOTIFIER);
9509
9510 cpuhp_setup_state(CPUHP_AP_X86_KVM_CLK_ONLINE, "x86/kvm/clk:online",
9511 kvmclock_cpu_online, kvmclock_cpu_down_prep);
9512 }
9513 }
9514
9515 #ifdef CONFIG_X86_64
pvclock_gtod_update_fn(struct work_struct * work)9516 static void pvclock_gtod_update_fn(struct work_struct *work)
9517 {
9518 struct kvm *kvm;
9519 struct kvm_vcpu *vcpu;
9520 unsigned long i;
9521
9522 mutex_lock(&kvm_lock);
9523 list_for_each_entry(kvm, &vm_list, vm_list)
9524 kvm_for_each_vcpu(i, vcpu, kvm)
9525 kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
9526 atomic_set(&kvm_guest_has_master_clock, 0);
9527 mutex_unlock(&kvm_lock);
9528 }
9529
9530 static DECLARE_WORK(pvclock_gtod_work, pvclock_gtod_update_fn);
9531
9532 /*
9533 * Indirection to move queue_work() out of the tk_core.seq write held
9534 * region to prevent possible deadlocks against time accessors which
9535 * are invoked with work related locks held.
9536 */
pvclock_irq_work_fn(struct irq_work * w)9537 static void pvclock_irq_work_fn(struct irq_work *w)
9538 {
9539 queue_work(system_long_wq, &pvclock_gtod_work);
9540 }
9541
9542 static DEFINE_IRQ_WORK(pvclock_irq_work, pvclock_irq_work_fn);
9543
9544 /*
9545 * Notification about pvclock gtod data update.
9546 */
pvclock_gtod_notify(struct notifier_block * nb,unsigned long unused,void * priv)9547 static int pvclock_gtod_notify(struct notifier_block *nb, unsigned long unused,
9548 void *priv)
9549 {
9550 struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
9551 struct timekeeper *tk = priv;
9552
9553 update_pvclock_gtod(tk);
9554
9555 /*
9556 * Disable master clock if host does not trust, or does not use,
9557 * TSC based clocksource. Delegate queue_work() to irq_work as
9558 * this is invoked with tk_core.seq write held.
9559 */
9560 if (!gtod_is_based_on_tsc(gtod->clock.vclock_mode) &&
9561 atomic_read(&kvm_guest_has_master_clock) != 0)
9562 irq_work_queue(&pvclock_irq_work);
9563 return 0;
9564 }
9565
9566 static struct notifier_block pvclock_gtod_notifier = {
9567 .notifier_call = pvclock_gtod_notify,
9568 };
9569 #endif
9570
kvm_ops_update(struct kvm_x86_init_ops * ops)9571 static inline void kvm_ops_update(struct kvm_x86_init_ops *ops)
9572 {
9573 memcpy(&kvm_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops));
9574
9575 #define __KVM_X86_OP(func) \
9576 static_call_update(kvm_x86_##func, kvm_x86_ops.func);
9577 #define KVM_X86_OP(func) \
9578 WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func)
9579 #define KVM_X86_OP_OPTIONAL __KVM_X86_OP
9580 #define KVM_X86_OP_OPTIONAL_RET0(func) \
9581 static_call_update(kvm_x86_##func, (void *)kvm_x86_ops.func ? : \
9582 (void *)__static_call_return0);
9583 #include <asm/kvm-x86-ops.h>
9584 #undef __KVM_X86_OP
9585
9586 kvm_pmu_ops_update(ops->pmu_ops);
9587 }
9588
kvm_x86_check_processor_compatibility(void)9589 static int kvm_x86_check_processor_compatibility(void)
9590 {
9591 int cpu = smp_processor_id();
9592 struct cpuinfo_x86 *c = &cpu_data(cpu);
9593
9594 /*
9595 * Compatibility checks are done when loading KVM and when enabling
9596 * hardware, e.g. during CPU hotplug, to ensure all online CPUs are
9597 * compatible, i.e. KVM should never perform a compatibility check on
9598 * an offline CPU.
9599 */
9600 WARN_ON(!cpu_online(cpu));
9601
9602 if (__cr4_reserved_bits(cpu_has, c) !=
9603 __cr4_reserved_bits(cpu_has, &boot_cpu_data))
9604 return -EIO;
9605
9606 return kvm_x86_call(check_processor_compatibility)();
9607 }
9608
kvm_x86_check_cpu_compat(void * ret)9609 static void kvm_x86_check_cpu_compat(void *ret)
9610 {
9611 *(int *)ret = kvm_x86_check_processor_compatibility();
9612 }
9613
kvm_x86_vendor_init(struct kvm_x86_init_ops * ops)9614 int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
9615 {
9616 u64 host_pat;
9617 int r, cpu;
9618
9619 guard(mutex)(&vendor_module_lock);
9620
9621 if (kvm_x86_ops.enable_virtualization_cpu) {
9622 pr_err("already loaded vendor module '%s'\n", kvm_x86_ops.name);
9623 return -EEXIST;
9624 }
9625
9626 /*
9627 * KVM explicitly assumes that the guest has an FPU and
9628 * FXSAVE/FXRSTOR. For example, the KVM_GET_FPU explicitly casts the
9629 * vCPU's FPU state as a fxregs_state struct.
9630 */
9631 if (!boot_cpu_has(X86_FEATURE_FPU) || !boot_cpu_has(X86_FEATURE_FXSR)) {
9632 pr_err("inadequate fpu\n");
9633 return -EOPNOTSUPP;
9634 }
9635
9636 if (IS_ENABLED(CONFIG_PREEMPT_RT) && !boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9637 pr_err("RT requires X86_FEATURE_CONSTANT_TSC\n");
9638 return -EOPNOTSUPP;
9639 }
9640
9641 /*
9642 * KVM assumes that PAT entry '0' encodes WB memtype and simply zeroes
9643 * the PAT bits in SPTEs. Bail if PAT[0] is programmed to something
9644 * other than WB. Note, EPT doesn't utilize the PAT, but don't bother
9645 * with an exception. PAT[0] is set to WB on RESET and also by the
9646 * kernel, i.e. failure indicates a kernel bug or broken firmware.
9647 */
9648 if (rdmsrq_safe(MSR_IA32_CR_PAT, &host_pat) ||
9649 (host_pat & GENMASK(2, 0)) != 6) {
9650 pr_err("host PAT[0] is not WB\n");
9651 return -EIO;
9652 }
9653
9654 memset(&kvm_caps, 0, sizeof(kvm_caps));
9655
9656 x86_emulator_cache = kvm_alloc_emulator_cache();
9657 if (!x86_emulator_cache) {
9658 pr_err("failed to allocate cache for x86 emulator\n");
9659 return -ENOMEM;
9660 }
9661
9662 user_return_msrs = alloc_percpu(struct kvm_user_return_msrs);
9663 if (!user_return_msrs) {
9664 pr_err("failed to allocate percpu kvm_user_return_msrs\n");
9665 r = -ENOMEM;
9666 goto out_free_x86_emulator_cache;
9667 }
9668 kvm_nr_uret_msrs = 0;
9669
9670 r = kvm_mmu_vendor_module_init();
9671 if (r)
9672 goto out_free_percpu;
9673
9674 kvm_caps.supported_vm_types = BIT(KVM_X86_DEFAULT_VM);
9675 kvm_caps.supported_mce_cap = MCG_CTL_P | MCG_SER_P;
9676
9677 if (boot_cpu_has(X86_FEATURE_XSAVE)) {
9678 kvm_host.xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
9679 kvm_caps.supported_xcr0 = kvm_host.xcr0 & KVM_SUPPORTED_XCR0;
9680 }
9681 kvm_caps.supported_quirks = KVM_X86_VALID_QUIRKS;
9682 kvm_caps.inapplicable_quirks = KVM_X86_CONDITIONAL_QUIRKS;
9683
9684 rdmsrq_safe(MSR_EFER, &kvm_host.efer);
9685
9686 if (boot_cpu_has(X86_FEATURE_XSAVES))
9687 rdmsrq(MSR_IA32_XSS, kvm_host.xss);
9688
9689 kvm_init_pmu_capability(ops->pmu_ops);
9690
9691 if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES))
9692 rdmsrq(MSR_IA32_ARCH_CAPABILITIES, kvm_host.arch_capabilities);
9693
9694 r = ops->hardware_setup();
9695 if (r != 0)
9696 goto out_mmu_exit;
9697
9698 enable_device_posted_irqs &= enable_apicv &&
9699 irq_remapping_cap(IRQ_POSTING_CAP);
9700
9701 kvm_ops_update(ops);
9702
9703 for_each_online_cpu(cpu) {
9704 smp_call_function_single(cpu, kvm_x86_check_cpu_compat, &r, 1);
9705 if (r < 0)
9706 goto out_unwind_ops;
9707 }
9708
9709 /*
9710 * Point of no return! DO NOT add error paths below this point unless
9711 * absolutely necessary, as most operations from this point forward
9712 * require unwinding.
9713 */
9714 kvm_timer_init();
9715
9716 if (pi_inject_timer == -1)
9717 pi_inject_timer = housekeeping_enabled(HK_TYPE_TIMER);
9718 #ifdef CONFIG_X86_64
9719 pvclock_gtod_register_notifier(&pvclock_gtod_notifier);
9720
9721 if (hypervisor_is_type(X86_HYPER_MS_HYPERV))
9722 set_hv_tscchange_cb(kvm_hyperv_tsc_notifier);
9723 #endif
9724
9725 kvm_register_perf_callbacks(ops->handle_intel_pt_intr);
9726
9727 if (IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_mmu_enabled)
9728 kvm_caps.supported_vm_types |= BIT(KVM_X86_SW_PROTECTED_VM);
9729
9730 /* KVM always ignores guest PAT for shadow paging. */
9731 if (!tdp_enabled)
9732 kvm_caps.supported_quirks &= ~KVM_X86_QUIRK_IGNORE_GUEST_PAT;
9733
9734 if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES))
9735 kvm_caps.supported_xss = 0;
9736
9737 if (kvm_caps.has_tsc_control) {
9738 /*
9739 * Make sure the user can only configure tsc_khz values that
9740 * fit into a signed integer.
9741 * A min value is not calculated because it will always
9742 * be 1 on all machines.
9743 */
9744 u64 max = min(0x7fffffffULL,
9745 __scale_tsc(kvm_caps.max_tsc_scaling_ratio, tsc_khz));
9746 kvm_caps.max_guest_tsc_khz = max;
9747 }
9748 kvm_caps.default_tsc_scaling_ratio = 1ULL << kvm_caps.tsc_scaling_ratio_frac_bits;
9749 kvm_init_msr_lists();
9750 return 0;
9751
9752 out_unwind_ops:
9753 kvm_x86_ops.enable_virtualization_cpu = NULL;
9754 kvm_x86_call(hardware_unsetup)();
9755 out_mmu_exit:
9756 kvm_mmu_vendor_module_exit();
9757 out_free_percpu:
9758 free_percpu(user_return_msrs);
9759 out_free_x86_emulator_cache:
9760 kmem_cache_destroy(x86_emulator_cache);
9761 return r;
9762 }
9763 EXPORT_SYMBOL_GPL(kvm_x86_vendor_init);
9764
kvm_x86_vendor_exit(void)9765 void kvm_x86_vendor_exit(void)
9766 {
9767 kvm_unregister_perf_callbacks();
9768
9769 #ifdef CONFIG_X86_64
9770 if (hypervisor_is_type(X86_HYPER_MS_HYPERV))
9771 clear_hv_tscchange_cb();
9772 #endif
9773 kvm_lapic_exit();
9774
9775 if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9776 cpufreq_unregister_notifier(&kvmclock_cpufreq_notifier_block,
9777 CPUFREQ_TRANSITION_NOTIFIER);
9778 cpuhp_remove_state_nocalls(CPUHP_AP_X86_KVM_CLK_ONLINE);
9779 }
9780 #ifdef CONFIG_X86_64
9781 pvclock_gtod_unregister_notifier(&pvclock_gtod_notifier);
9782 irq_work_sync(&pvclock_irq_work);
9783 cancel_work_sync(&pvclock_gtod_work);
9784 #endif
9785 kvm_x86_call(hardware_unsetup)();
9786 kvm_mmu_vendor_module_exit();
9787 free_percpu(user_return_msrs);
9788 kmem_cache_destroy(x86_emulator_cache);
9789 #ifdef CONFIG_KVM_XEN
9790 static_key_deferred_flush(&kvm_xen_enabled);
9791 WARN_ON(static_branch_unlikely(&kvm_xen_enabled.key));
9792 #endif
9793 mutex_lock(&vendor_module_lock);
9794 kvm_x86_ops.enable_virtualization_cpu = NULL;
9795 mutex_unlock(&vendor_module_lock);
9796 }
9797 EXPORT_SYMBOL_GPL(kvm_x86_vendor_exit);
9798
9799 #ifdef CONFIG_X86_64
kvm_pv_clock_pairing(struct kvm_vcpu * vcpu,gpa_t paddr,unsigned long clock_type)9800 static int kvm_pv_clock_pairing(struct kvm_vcpu *vcpu, gpa_t paddr,
9801 unsigned long clock_type)
9802 {
9803 struct kvm_clock_pairing clock_pairing;
9804 struct timespec64 ts;
9805 u64 cycle;
9806 int ret;
9807
9808 if (clock_type != KVM_CLOCK_PAIRING_WALLCLOCK)
9809 return -KVM_EOPNOTSUPP;
9810
9811 /*
9812 * When tsc is in permanent catchup mode guests won't be able to use
9813 * pvclock_read_retry loop to get consistent view of pvclock
9814 */
9815 if (vcpu->arch.tsc_always_catchup)
9816 return -KVM_EOPNOTSUPP;
9817
9818 if (!kvm_get_walltime_and_clockread(&ts, &cycle))
9819 return -KVM_EOPNOTSUPP;
9820
9821 clock_pairing.sec = ts.tv_sec;
9822 clock_pairing.nsec = ts.tv_nsec;
9823 clock_pairing.tsc = kvm_read_l1_tsc(vcpu, cycle);
9824 clock_pairing.flags = 0;
9825 memset(&clock_pairing.pad, 0, sizeof(clock_pairing.pad));
9826
9827 ret = 0;
9828 if (kvm_write_guest(vcpu->kvm, paddr, &clock_pairing,
9829 sizeof(struct kvm_clock_pairing)))
9830 ret = -KVM_EFAULT;
9831
9832 return ret;
9833 }
9834 #endif
9835
9836 /*
9837 * kvm_pv_kick_cpu_op: Kick a vcpu.
9838 *
9839 * @apicid - apicid of vcpu to be kicked.
9840 */
kvm_pv_kick_cpu_op(struct kvm * kvm,int apicid)9841 static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid)
9842 {
9843 /*
9844 * All other fields are unused for APIC_DM_REMRD, but may be consumed by
9845 * common code, e.g. for tracing. Defer initialization to the compiler.
9846 */
9847 struct kvm_lapic_irq lapic_irq = {
9848 .delivery_mode = APIC_DM_REMRD,
9849 .dest_mode = APIC_DEST_PHYSICAL,
9850 .shorthand = APIC_DEST_NOSHORT,
9851 .dest_id = apicid,
9852 };
9853
9854 kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL);
9855 }
9856
kvm_apicv_activated(struct kvm * kvm)9857 bool kvm_apicv_activated(struct kvm *kvm)
9858 {
9859 return (READ_ONCE(kvm->arch.apicv_inhibit_reasons) == 0);
9860 }
9861 EXPORT_SYMBOL_GPL(kvm_apicv_activated);
9862
kvm_vcpu_apicv_activated(struct kvm_vcpu * vcpu)9863 bool kvm_vcpu_apicv_activated(struct kvm_vcpu *vcpu)
9864 {
9865 ulong vm_reasons = READ_ONCE(vcpu->kvm->arch.apicv_inhibit_reasons);
9866 ulong vcpu_reasons =
9867 kvm_x86_call(vcpu_get_apicv_inhibit_reasons)(vcpu);
9868
9869 return (vm_reasons | vcpu_reasons) == 0;
9870 }
9871 EXPORT_SYMBOL_GPL(kvm_vcpu_apicv_activated);
9872
set_or_clear_apicv_inhibit(unsigned long * inhibits,enum kvm_apicv_inhibit reason,bool set)9873 static void set_or_clear_apicv_inhibit(unsigned long *inhibits,
9874 enum kvm_apicv_inhibit reason, bool set)
9875 {
9876 const struct trace_print_flags apicv_inhibits[] = { APICV_INHIBIT_REASONS };
9877
9878 BUILD_BUG_ON(ARRAY_SIZE(apicv_inhibits) != NR_APICV_INHIBIT_REASONS);
9879
9880 if (set)
9881 __set_bit(reason, inhibits);
9882 else
9883 __clear_bit(reason, inhibits);
9884
9885 trace_kvm_apicv_inhibit_changed(reason, set, *inhibits);
9886 }
9887
kvm_apicv_init(struct kvm * kvm)9888 static void kvm_apicv_init(struct kvm *kvm)
9889 {
9890 enum kvm_apicv_inhibit reason = enable_apicv ? APICV_INHIBIT_REASON_ABSENT :
9891 APICV_INHIBIT_REASON_DISABLED;
9892
9893 set_or_clear_apicv_inhibit(&kvm->arch.apicv_inhibit_reasons, reason, true);
9894
9895 init_rwsem(&kvm->arch.apicv_update_lock);
9896 }
9897
kvm_sched_yield(struct kvm_vcpu * vcpu,unsigned long dest_id)9898 static void kvm_sched_yield(struct kvm_vcpu *vcpu, unsigned long dest_id)
9899 {
9900 struct kvm_vcpu *target = NULL;
9901 struct kvm_apic_map *map;
9902
9903 vcpu->stat.directed_yield_attempted++;
9904
9905 if (single_task_running())
9906 goto no_yield;
9907
9908 rcu_read_lock();
9909 map = rcu_dereference(vcpu->kvm->arch.apic_map);
9910
9911 if (likely(map) && dest_id <= map->max_apic_id && map->phys_map[dest_id])
9912 target = map->phys_map[dest_id]->vcpu;
9913
9914 rcu_read_unlock();
9915
9916 if (!target || !READ_ONCE(target->ready))
9917 goto no_yield;
9918
9919 /* Ignore requests to yield to self */
9920 if (vcpu == target)
9921 goto no_yield;
9922
9923 if (kvm_vcpu_yield_to(target) <= 0)
9924 goto no_yield;
9925
9926 vcpu->stat.directed_yield_successful++;
9927
9928 no_yield:
9929 return;
9930 }
9931
complete_hypercall_exit(struct kvm_vcpu * vcpu)9932 static int complete_hypercall_exit(struct kvm_vcpu *vcpu)
9933 {
9934 u64 ret = vcpu->run->hypercall.ret;
9935
9936 if (!is_64_bit_hypercall(vcpu))
9937 ret = (u32)ret;
9938 kvm_rax_write(vcpu, ret);
9939 return kvm_skip_emulated_instruction(vcpu);
9940 }
9941
____kvm_emulate_hypercall(struct kvm_vcpu * vcpu,int cpl,int (* complete_hypercall)(struct kvm_vcpu *))9942 int ____kvm_emulate_hypercall(struct kvm_vcpu *vcpu, int cpl,
9943 int (*complete_hypercall)(struct kvm_vcpu *))
9944 {
9945 unsigned long ret;
9946 unsigned long nr = kvm_rax_read(vcpu);
9947 unsigned long a0 = kvm_rbx_read(vcpu);
9948 unsigned long a1 = kvm_rcx_read(vcpu);
9949 unsigned long a2 = kvm_rdx_read(vcpu);
9950 unsigned long a3 = kvm_rsi_read(vcpu);
9951 int op_64_bit = is_64_bit_hypercall(vcpu);
9952
9953 ++vcpu->stat.hypercalls;
9954
9955 trace_kvm_hypercall(nr, a0, a1, a2, a3);
9956
9957 if (!op_64_bit) {
9958 nr &= 0xFFFFFFFF;
9959 a0 &= 0xFFFFFFFF;
9960 a1 &= 0xFFFFFFFF;
9961 a2 &= 0xFFFFFFFF;
9962 a3 &= 0xFFFFFFFF;
9963 }
9964
9965 if (cpl) {
9966 ret = -KVM_EPERM;
9967 goto out;
9968 }
9969
9970 ret = -KVM_ENOSYS;
9971
9972 switch (nr) {
9973 case KVM_HC_VAPIC_POLL_IRQ:
9974 ret = 0;
9975 break;
9976 case KVM_HC_KICK_CPU:
9977 if (!guest_pv_has(vcpu, KVM_FEATURE_PV_UNHALT))
9978 break;
9979
9980 kvm_pv_kick_cpu_op(vcpu->kvm, a1);
9981 kvm_sched_yield(vcpu, a1);
9982 ret = 0;
9983 break;
9984 #ifdef CONFIG_X86_64
9985 case KVM_HC_CLOCK_PAIRING:
9986 ret = kvm_pv_clock_pairing(vcpu, a0, a1);
9987 break;
9988 #endif
9989 case KVM_HC_SEND_IPI:
9990 if (!guest_pv_has(vcpu, KVM_FEATURE_PV_SEND_IPI))
9991 break;
9992
9993 ret = kvm_pv_send_ipi(vcpu->kvm, a0, a1, a2, a3, op_64_bit);
9994 break;
9995 case KVM_HC_SCHED_YIELD:
9996 if (!guest_pv_has(vcpu, KVM_FEATURE_PV_SCHED_YIELD))
9997 break;
9998
9999 kvm_sched_yield(vcpu, a0);
10000 ret = 0;
10001 break;
10002 case KVM_HC_MAP_GPA_RANGE: {
10003 u64 gpa = a0, npages = a1, attrs = a2;
10004
10005 ret = -KVM_ENOSYS;
10006 if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE))
10007 break;
10008
10009 if (!PAGE_ALIGNED(gpa) || !npages ||
10010 gpa_to_gfn(gpa) + npages <= gpa_to_gfn(gpa)) {
10011 ret = -KVM_EINVAL;
10012 break;
10013 }
10014
10015 vcpu->run->exit_reason = KVM_EXIT_HYPERCALL;
10016 vcpu->run->hypercall.nr = KVM_HC_MAP_GPA_RANGE;
10017 /*
10018 * In principle this should have been -KVM_ENOSYS, but userspace (QEMU <=9.2)
10019 * assumed that vcpu->run->hypercall.ret is never changed by KVM and thus that
10020 * it was always zero on KVM_EXIT_HYPERCALL. Since KVM is now overwriting
10021 * vcpu->run->hypercall.ret, ensuring that it is zero to not break QEMU.
10022 */
10023 vcpu->run->hypercall.ret = 0;
10024 vcpu->run->hypercall.args[0] = gpa;
10025 vcpu->run->hypercall.args[1] = npages;
10026 vcpu->run->hypercall.args[2] = attrs;
10027 vcpu->run->hypercall.flags = 0;
10028 if (op_64_bit)
10029 vcpu->run->hypercall.flags |= KVM_EXIT_HYPERCALL_LONG_MODE;
10030
10031 WARN_ON_ONCE(vcpu->run->hypercall.flags & KVM_EXIT_HYPERCALL_MBZ);
10032 vcpu->arch.complete_userspace_io = complete_hypercall;
10033 return 0;
10034 }
10035 default:
10036 ret = -KVM_ENOSYS;
10037 break;
10038 }
10039
10040 out:
10041 vcpu->run->hypercall.ret = ret;
10042 return 1;
10043 }
10044 EXPORT_SYMBOL_GPL(____kvm_emulate_hypercall);
10045
kvm_emulate_hypercall(struct kvm_vcpu * vcpu)10046 int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
10047 {
10048 if (kvm_xen_hypercall_enabled(vcpu->kvm))
10049 return kvm_xen_hypercall(vcpu);
10050
10051 if (kvm_hv_hypercall_enabled(vcpu))
10052 return kvm_hv_hypercall(vcpu);
10053
10054 return __kvm_emulate_hypercall(vcpu, kvm_x86_call(get_cpl)(vcpu),
10055 complete_hypercall_exit);
10056 }
10057 EXPORT_SYMBOL_GPL(kvm_emulate_hypercall);
10058
emulator_fix_hypercall(struct x86_emulate_ctxt * ctxt)10059 static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt)
10060 {
10061 struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
10062 char instruction[3];
10063 unsigned long rip = kvm_rip_read(vcpu);
10064
10065 /*
10066 * If the quirk is disabled, synthesize a #UD and let the guest pick up
10067 * the pieces.
10068 */
10069 if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_FIX_HYPERCALL_INSN)) {
10070 ctxt->exception.error_code_valid = false;
10071 ctxt->exception.vector = UD_VECTOR;
10072 ctxt->have_exception = true;
10073 return X86EMUL_PROPAGATE_FAULT;
10074 }
10075
10076 kvm_x86_call(patch_hypercall)(vcpu, instruction);
10077
10078 return emulator_write_emulated(ctxt, rip, instruction, 3,
10079 &ctxt->exception);
10080 }
10081
dm_request_for_irq_injection(struct kvm_vcpu * vcpu)10082 static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu)
10083 {
10084 return vcpu->run->request_interrupt_window &&
10085 likely(!pic_in_kernel(vcpu->kvm));
10086 }
10087
10088 /* Called within kvm->srcu read side. */
post_kvm_run_save(struct kvm_vcpu * vcpu)10089 static void post_kvm_run_save(struct kvm_vcpu *vcpu)
10090 {
10091 struct kvm_run *kvm_run = vcpu->run;
10092
10093 kvm_run->if_flag = kvm_x86_call(get_if_flag)(vcpu);
10094 kvm_run->cr8 = kvm_get_cr8(vcpu);
10095 kvm_run->apic_base = vcpu->arch.apic_base;
10096
10097 kvm_run->ready_for_interrupt_injection =
10098 pic_in_kernel(vcpu->kvm) ||
10099 kvm_vcpu_ready_for_interrupt_injection(vcpu);
10100
10101 if (is_smm(vcpu))
10102 kvm_run->flags |= KVM_RUN_X86_SMM;
10103 if (is_guest_mode(vcpu))
10104 kvm_run->flags |= KVM_RUN_X86_GUEST_MODE;
10105 }
10106
update_cr8_intercept(struct kvm_vcpu * vcpu)10107 static void update_cr8_intercept(struct kvm_vcpu *vcpu)
10108 {
10109 int max_irr, tpr;
10110
10111 if (!kvm_x86_ops.update_cr8_intercept)
10112 return;
10113
10114 if (!lapic_in_kernel(vcpu))
10115 return;
10116
10117 if (vcpu->arch.apic->apicv_active)
10118 return;
10119
10120 if (!vcpu->arch.apic->vapic_addr)
10121 max_irr = kvm_lapic_find_highest_irr(vcpu);
10122 else
10123 max_irr = -1;
10124
10125 if (max_irr != -1)
10126 max_irr >>= 4;
10127
10128 tpr = kvm_lapic_get_cr8(vcpu);
10129
10130 kvm_x86_call(update_cr8_intercept)(vcpu, tpr, max_irr);
10131 }
10132
10133
kvm_check_nested_events(struct kvm_vcpu * vcpu)10134 int kvm_check_nested_events(struct kvm_vcpu *vcpu)
10135 {
10136 if (kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu)) {
10137 kvm_x86_ops.nested_ops->triple_fault(vcpu);
10138 return 1;
10139 }
10140
10141 return kvm_x86_ops.nested_ops->check_events(vcpu);
10142 }
10143
kvm_inject_exception(struct kvm_vcpu * vcpu)10144 static void kvm_inject_exception(struct kvm_vcpu *vcpu)
10145 {
10146 /*
10147 * Suppress the error code if the vCPU is in Real Mode, as Real Mode
10148 * exceptions don't report error codes. The presence of an error code
10149 * is carried with the exception and only stripped when the exception
10150 * is injected as intercepted #PF VM-Exits for AMD's Paged Real Mode do
10151 * report an error code despite the CPU being in Real Mode.
10152 */
10153 vcpu->arch.exception.has_error_code &= is_protmode(vcpu);
10154
10155 trace_kvm_inj_exception(vcpu->arch.exception.vector,
10156 vcpu->arch.exception.has_error_code,
10157 vcpu->arch.exception.error_code,
10158 vcpu->arch.exception.injected);
10159
10160 kvm_x86_call(inject_exception)(vcpu);
10161 }
10162
10163 /*
10164 * Check for any event (interrupt or exception) that is ready to be injected,
10165 * and if there is at least one event, inject the event with the highest
10166 * priority. This handles both "pending" events, i.e. events that have never
10167 * been injected into the guest, and "injected" events, i.e. events that were
10168 * injected as part of a previous VM-Enter, but weren't successfully delivered
10169 * and need to be re-injected.
10170 *
10171 * Note, this is not guaranteed to be invoked on a guest instruction boundary,
10172 * i.e. doesn't guarantee that there's an event window in the guest. KVM must
10173 * be able to inject exceptions in the "middle" of an instruction, and so must
10174 * also be able to re-inject NMIs and IRQs in the middle of an instruction.
10175 * I.e. for exceptions and re-injected events, NOT invoking this on instruction
10176 * boundaries is necessary and correct.
10177 *
10178 * For simplicity, KVM uses a single path to inject all events (except events
10179 * that are injected directly from L1 to L2) and doesn't explicitly track
10180 * instruction boundaries for asynchronous events. However, because VM-Exits
10181 * that can occur during instruction execution typically result in KVM skipping
10182 * the instruction or injecting an exception, e.g. instruction and exception
10183 * intercepts, and because pending exceptions have higher priority than pending
10184 * interrupts, KVM still honors instruction boundaries in most scenarios.
10185 *
10186 * But, if a VM-Exit occurs during instruction execution, and KVM does NOT skip
10187 * the instruction or inject an exception, then KVM can incorrecty inject a new
10188 * asynchronous event if the event became pending after the CPU fetched the
10189 * instruction (in the guest). E.g. if a page fault (#PF, #NPF, EPT violation)
10190 * occurs and is resolved by KVM, a coincident NMI, SMI, IRQ, etc... can be
10191 * injected on the restarted instruction instead of being deferred until the
10192 * instruction completes.
10193 *
10194 * In practice, this virtualization hole is unlikely to be observed by the
10195 * guest, and even less likely to cause functional problems. To detect the
10196 * hole, the guest would have to trigger an event on a side effect of an early
10197 * phase of instruction execution, e.g. on the instruction fetch from memory.
10198 * And for it to be a functional problem, the guest would need to depend on the
10199 * ordering between that side effect, the instruction completing, _and_ the
10200 * delivery of the asynchronous event.
10201 */
kvm_check_and_inject_events(struct kvm_vcpu * vcpu,bool * req_immediate_exit)10202 static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
10203 bool *req_immediate_exit)
10204 {
10205 bool can_inject;
10206 int r;
10207
10208 /*
10209 * Process nested events first, as nested VM-Exit supersedes event
10210 * re-injection. If there's an event queued for re-injection, it will
10211 * be saved into the appropriate vmc{b,s}12 fields on nested VM-Exit.
10212 */
10213 if (is_guest_mode(vcpu))
10214 r = kvm_check_nested_events(vcpu);
10215 else
10216 r = 0;
10217
10218 /*
10219 * Re-inject exceptions and events *especially* if immediate entry+exit
10220 * to/from L2 is needed, as any event that has already been injected
10221 * into L2 needs to complete its lifecycle before injecting a new event.
10222 *
10223 * Don't re-inject an NMI or interrupt if there is a pending exception.
10224 * This collision arises if an exception occurred while vectoring the
10225 * injected event, KVM intercepted said exception, and KVM ultimately
10226 * determined the fault belongs to the guest and queues the exception
10227 * for injection back into the guest.
10228 *
10229 * "Injected" interrupts can also collide with pending exceptions if
10230 * userspace ignores the "ready for injection" flag and blindly queues
10231 * an interrupt. In that case, prioritizing the exception is correct,
10232 * as the exception "occurred" before the exit to userspace. Trap-like
10233 * exceptions, e.g. most #DBs, have higher priority than interrupts.
10234 * And while fault-like exceptions, e.g. #GP and #PF, are the lowest
10235 * priority, they're only generated (pended) during instruction
10236 * execution, and interrupts are recognized at instruction boundaries.
10237 * Thus a pending fault-like exception means the fault occurred on the
10238 * *previous* instruction and must be serviced prior to recognizing any
10239 * new events in order to fully complete the previous instruction.
10240 */
10241 if (vcpu->arch.exception.injected)
10242 kvm_inject_exception(vcpu);
10243 else if (kvm_is_exception_pending(vcpu))
10244 ; /* see above */
10245 else if (vcpu->arch.nmi_injected)
10246 kvm_x86_call(inject_nmi)(vcpu);
10247 else if (vcpu->arch.interrupt.injected)
10248 kvm_x86_call(inject_irq)(vcpu, true);
10249
10250 /*
10251 * Exceptions that morph to VM-Exits are handled above, and pending
10252 * exceptions on top of injected exceptions that do not VM-Exit should
10253 * either morph to #DF or, sadly, override the injected exception.
10254 */
10255 WARN_ON_ONCE(vcpu->arch.exception.injected &&
10256 vcpu->arch.exception.pending);
10257
10258 /*
10259 * Bail if immediate entry+exit to/from the guest is needed to complete
10260 * nested VM-Enter or event re-injection so that a different pending
10261 * event can be serviced (or if KVM needs to exit to userspace).
10262 *
10263 * Otherwise, continue processing events even if VM-Exit occurred. The
10264 * VM-Exit will have cleared exceptions that were meant for L2, but
10265 * there may now be events that can be injected into L1.
10266 */
10267 if (r < 0)
10268 goto out;
10269
10270 /*
10271 * A pending exception VM-Exit should either result in nested VM-Exit
10272 * or force an immediate re-entry and exit to/from L2, and exception
10273 * VM-Exits cannot be injected (flag should _never_ be set).
10274 */
10275 WARN_ON_ONCE(vcpu->arch.exception_vmexit.injected ||
10276 vcpu->arch.exception_vmexit.pending);
10277
10278 /*
10279 * New events, other than exceptions, cannot be injected if KVM needs
10280 * to re-inject a previous event. See above comments on re-injecting
10281 * for why pending exceptions get priority.
10282 */
10283 can_inject = !kvm_event_needs_reinjection(vcpu);
10284
10285 if (vcpu->arch.exception.pending) {
10286 /*
10287 * Fault-class exceptions, except #DBs, set RF=1 in the RFLAGS
10288 * value pushed on the stack. Trap-like exception and all #DBs
10289 * leave RF as-is (KVM follows Intel's behavior in this regard;
10290 * AMD states that code breakpoint #DBs excplitly clear RF=0).
10291 *
10292 * Note, most versions of Intel's SDM and AMD's APM incorrectly
10293 * describe the behavior of General Detect #DBs, which are
10294 * fault-like. They do _not_ set RF, a la code breakpoints.
10295 */
10296 if (exception_type(vcpu->arch.exception.vector) == EXCPT_FAULT)
10297 __kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) |
10298 X86_EFLAGS_RF);
10299
10300 if (vcpu->arch.exception.vector == DB_VECTOR) {
10301 kvm_deliver_exception_payload(vcpu, &vcpu->arch.exception);
10302 if (vcpu->arch.dr7 & DR7_GD) {
10303 vcpu->arch.dr7 &= ~DR7_GD;
10304 kvm_update_dr7(vcpu);
10305 }
10306 }
10307
10308 kvm_inject_exception(vcpu);
10309
10310 vcpu->arch.exception.pending = false;
10311 vcpu->arch.exception.injected = true;
10312
10313 can_inject = false;
10314 }
10315
10316 /* Don't inject interrupts if the user asked to avoid doing so */
10317 if (vcpu->guest_debug & KVM_GUESTDBG_BLOCKIRQ)
10318 return 0;
10319
10320 /*
10321 * Finally, inject interrupt events. If an event cannot be injected
10322 * due to architectural conditions (e.g. IF=0) a window-open exit
10323 * will re-request KVM_REQ_EVENT. Sometimes however an event is pending
10324 * and can architecturally be injected, but we cannot do it right now:
10325 * an interrupt could have arrived just now and we have to inject it
10326 * as a vmexit, or there could already an event in the queue, which is
10327 * indicated by can_inject. In that case we request an immediate exit
10328 * in order to make progress and get back here for another iteration.
10329 * The kvm_x86_ops hooks communicate this by returning -EBUSY.
10330 */
10331 #ifdef CONFIG_KVM_SMM
10332 if (vcpu->arch.smi_pending) {
10333 r = can_inject ? kvm_x86_call(smi_allowed)(vcpu, true) :
10334 -EBUSY;
10335 if (r < 0)
10336 goto out;
10337 if (r) {
10338 vcpu->arch.smi_pending = false;
10339 ++vcpu->arch.smi_count;
10340 enter_smm(vcpu);
10341 can_inject = false;
10342 } else
10343 kvm_x86_call(enable_smi_window)(vcpu);
10344 }
10345 #endif
10346
10347 if (vcpu->arch.nmi_pending) {
10348 r = can_inject ? kvm_x86_call(nmi_allowed)(vcpu, true) :
10349 -EBUSY;
10350 if (r < 0)
10351 goto out;
10352 if (r) {
10353 --vcpu->arch.nmi_pending;
10354 vcpu->arch.nmi_injected = true;
10355 kvm_x86_call(inject_nmi)(vcpu);
10356 can_inject = false;
10357 WARN_ON(kvm_x86_call(nmi_allowed)(vcpu, true) < 0);
10358 }
10359 if (vcpu->arch.nmi_pending)
10360 kvm_x86_call(enable_nmi_window)(vcpu);
10361 }
10362
10363 if (kvm_cpu_has_injectable_intr(vcpu)) {
10364 r = can_inject ? kvm_x86_call(interrupt_allowed)(vcpu, true) :
10365 -EBUSY;
10366 if (r < 0)
10367 goto out;
10368 if (r) {
10369 int irq = kvm_cpu_get_interrupt(vcpu);
10370
10371 if (!WARN_ON_ONCE(irq == -1)) {
10372 kvm_queue_interrupt(vcpu, irq, false);
10373 kvm_x86_call(inject_irq)(vcpu, false);
10374 WARN_ON(kvm_x86_call(interrupt_allowed)(vcpu, true) < 0);
10375 }
10376 }
10377 if (kvm_cpu_has_injectable_intr(vcpu))
10378 kvm_x86_call(enable_irq_window)(vcpu);
10379 }
10380
10381 if (is_guest_mode(vcpu) &&
10382 kvm_x86_ops.nested_ops->has_events &&
10383 kvm_x86_ops.nested_ops->has_events(vcpu, true))
10384 *req_immediate_exit = true;
10385
10386 /*
10387 * KVM must never queue a new exception while injecting an event; KVM
10388 * is done emulating and should only propagate the to-be-injected event
10389 * to the VMCS/VMCB. Queueing a new exception can put the vCPU into an
10390 * infinite loop as KVM will bail from VM-Enter to inject the pending
10391 * exception and start the cycle all over.
10392 *
10393 * Exempt triple faults as they have special handling and won't put the
10394 * vCPU into an infinite loop. Triple fault can be queued when running
10395 * VMX without unrestricted guest, as that requires KVM to emulate Real
10396 * Mode events (see kvm_inject_realmode_interrupt()).
10397 */
10398 WARN_ON_ONCE(vcpu->arch.exception.pending ||
10399 vcpu->arch.exception_vmexit.pending);
10400 return 0;
10401
10402 out:
10403 if (r == -EBUSY) {
10404 *req_immediate_exit = true;
10405 r = 0;
10406 }
10407 return r;
10408 }
10409
process_nmi(struct kvm_vcpu * vcpu)10410 static void process_nmi(struct kvm_vcpu *vcpu)
10411 {
10412 unsigned int limit;
10413
10414 /*
10415 * x86 is limited to one NMI pending, but because KVM can't react to
10416 * incoming NMIs as quickly as bare metal, e.g. if the vCPU is
10417 * scheduled out, KVM needs to play nice with two queued NMIs showing
10418 * up at the same time. To handle this scenario, allow two NMIs to be
10419 * (temporarily) pending so long as NMIs are not blocked and KVM is not
10420 * waiting for a previous NMI injection to complete (which effectively
10421 * blocks NMIs). KVM will immediately inject one of the two NMIs, and
10422 * will request an NMI window to handle the second NMI.
10423 */
10424 if (kvm_x86_call(get_nmi_mask)(vcpu) || vcpu->arch.nmi_injected)
10425 limit = 1;
10426 else
10427 limit = 2;
10428
10429 /*
10430 * Adjust the limit to account for pending virtual NMIs, which aren't
10431 * tracked in vcpu->arch.nmi_pending.
10432 */
10433 if (kvm_x86_call(is_vnmi_pending)(vcpu))
10434 limit--;
10435
10436 vcpu->arch.nmi_pending += atomic_xchg(&vcpu->arch.nmi_queued, 0);
10437 vcpu->arch.nmi_pending = min(vcpu->arch.nmi_pending, limit);
10438
10439 if (vcpu->arch.nmi_pending &&
10440 (kvm_x86_call(set_vnmi_pending)(vcpu)))
10441 vcpu->arch.nmi_pending--;
10442
10443 if (vcpu->arch.nmi_pending)
10444 kvm_make_request(KVM_REQ_EVENT, vcpu);
10445 }
10446
10447 /* Return total number of NMIs pending injection to the VM */
kvm_get_nr_pending_nmis(struct kvm_vcpu * vcpu)10448 int kvm_get_nr_pending_nmis(struct kvm_vcpu *vcpu)
10449 {
10450 return vcpu->arch.nmi_pending +
10451 kvm_x86_call(is_vnmi_pending)(vcpu);
10452 }
10453
kvm_make_scan_ioapic_request_mask(struct kvm * kvm,unsigned long * vcpu_bitmap)10454 void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
10455 unsigned long *vcpu_bitmap)
10456 {
10457 kvm_make_vcpus_request_mask(kvm, KVM_REQ_SCAN_IOAPIC, vcpu_bitmap);
10458 }
10459
kvm_make_scan_ioapic_request(struct kvm * kvm)10460 void kvm_make_scan_ioapic_request(struct kvm *kvm)
10461 {
10462 kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
10463 }
10464
__kvm_vcpu_update_apicv(struct kvm_vcpu * vcpu)10465 void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
10466 {
10467 struct kvm_lapic *apic = vcpu->arch.apic;
10468 bool activate;
10469
10470 if (!lapic_in_kernel(vcpu))
10471 return;
10472
10473 down_read(&vcpu->kvm->arch.apicv_update_lock);
10474 preempt_disable();
10475
10476 /* Do not activate APICV when APIC is disabled */
10477 activate = kvm_vcpu_apicv_activated(vcpu) &&
10478 (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED);
10479
10480 if (apic->apicv_active == activate)
10481 goto out;
10482
10483 apic->apicv_active = activate;
10484 kvm_apic_update_apicv(vcpu);
10485 kvm_x86_call(refresh_apicv_exec_ctrl)(vcpu);
10486
10487 /*
10488 * When APICv gets disabled, we may still have injected interrupts
10489 * pending. At the same time, KVM_REQ_EVENT may not be set as APICv was
10490 * still active when the interrupt got accepted. Make sure
10491 * kvm_check_and_inject_events() is called to check for that.
10492 */
10493 if (!apic->apicv_active)
10494 kvm_make_request(KVM_REQ_EVENT, vcpu);
10495
10496 out:
10497 preempt_enable();
10498 up_read(&vcpu->kvm->arch.apicv_update_lock);
10499 }
10500 EXPORT_SYMBOL_GPL(__kvm_vcpu_update_apicv);
10501
kvm_vcpu_update_apicv(struct kvm_vcpu * vcpu)10502 static void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
10503 {
10504 if (!lapic_in_kernel(vcpu))
10505 return;
10506
10507 /*
10508 * Due to sharing page tables across vCPUs, the xAPIC memslot must be
10509 * deleted if any vCPU has xAPIC virtualization and x2APIC enabled, but
10510 * and hardware doesn't support x2APIC virtualization. E.g. some AMD
10511 * CPUs support AVIC but not x2APIC. KVM still allows enabling AVIC in
10512 * this case so that KVM can use the AVIC doorbell to inject interrupts
10513 * to running vCPUs, but KVM must not create SPTEs for the APIC base as
10514 * the vCPU would incorrectly be able to access the vAPIC page via MMIO
10515 * despite being in x2APIC mode. For simplicity, inhibiting the APIC
10516 * access page is sticky.
10517 */
10518 if (apic_x2apic_mode(vcpu->arch.apic) &&
10519 kvm_x86_ops.allow_apicv_in_x2apic_without_x2apic_virtualization)
10520 kvm_inhibit_apic_access_page(vcpu);
10521
10522 __kvm_vcpu_update_apicv(vcpu);
10523 }
10524
__kvm_set_or_clear_apicv_inhibit(struct kvm * kvm,enum kvm_apicv_inhibit reason,bool set)10525 void __kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
10526 enum kvm_apicv_inhibit reason, bool set)
10527 {
10528 unsigned long old, new;
10529
10530 lockdep_assert_held_write(&kvm->arch.apicv_update_lock);
10531
10532 if (!(kvm_x86_ops.required_apicv_inhibits & BIT(reason)))
10533 return;
10534
10535 old = new = kvm->arch.apicv_inhibit_reasons;
10536
10537 set_or_clear_apicv_inhibit(&new, reason, set);
10538
10539 if (!!old != !!new) {
10540 /*
10541 * Kick all vCPUs before setting apicv_inhibit_reasons to avoid
10542 * false positives in the sanity check WARN in vcpu_enter_guest().
10543 * This task will wait for all vCPUs to ack the kick IRQ before
10544 * updating apicv_inhibit_reasons, and all other vCPUs will
10545 * block on acquiring apicv_update_lock so that vCPUs can't
10546 * redo vcpu_enter_guest() without seeing the new inhibit state.
10547 *
10548 * Note, holding apicv_update_lock and taking it in the read
10549 * side (handling the request) also prevents other vCPUs from
10550 * servicing the request with a stale apicv_inhibit_reasons.
10551 */
10552 kvm_make_all_cpus_request(kvm, KVM_REQ_APICV_UPDATE);
10553 kvm->arch.apicv_inhibit_reasons = new;
10554 if (new) {
10555 unsigned long gfn = gpa_to_gfn(APIC_DEFAULT_PHYS_BASE);
10556 int idx = srcu_read_lock(&kvm->srcu);
10557
10558 kvm_zap_gfn_range(kvm, gfn, gfn+1);
10559 srcu_read_unlock(&kvm->srcu, idx);
10560 }
10561 } else {
10562 kvm->arch.apicv_inhibit_reasons = new;
10563 }
10564 }
10565
kvm_set_or_clear_apicv_inhibit(struct kvm * kvm,enum kvm_apicv_inhibit reason,bool set)10566 void kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
10567 enum kvm_apicv_inhibit reason, bool set)
10568 {
10569 if (!enable_apicv)
10570 return;
10571
10572 down_write(&kvm->arch.apicv_update_lock);
10573 __kvm_set_or_clear_apicv_inhibit(kvm, reason, set);
10574 up_write(&kvm->arch.apicv_update_lock);
10575 }
10576 EXPORT_SYMBOL_GPL(kvm_set_or_clear_apicv_inhibit);
10577
vcpu_scan_ioapic(struct kvm_vcpu * vcpu)10578 static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
10579 {
10580 if (!kvm_apic_present(vcpu))
10581 return;
10582
10583 bitmap_zero(vcpu->arch.ioapic_handled_vectors, 256);
10584 vcpu->arch.highest_stale_pending_ioapic_eoi = -1;
10585
10586 kvm_x86_call(sync_pir_to_irr)(vcpu);
10587
10588 if (irqchip_split(vcpu->kvm))
10589 kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors);
10590 #ifdef CONFIG_KVM_IOAPIC
10591 else if (ioapic_in_kernel(vcpu->kvm))
10592 kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors);
10593 #endif
10594
10595 if (is_guest_mode(vcpu))
10596 vcpu->arch.load_eoi_exitmap_pending = true;
10597 else
10598 kvm_make_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu);
10599 }
10600
vcpu_load_eoi_exitmap(struct kvm_vcpu * vcpu)10601 static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu)
10602 {
10603 if (!kvm_apic_hw_enabled(vcpu->arch.apic))
10604 return;
10605
10606 #ifdef CONFIG_KVM_HYPERV
10607 if (to_hv_vcpu(vcpu)) {
10608 u64 eoi_exit_bitmap[4];
10609
10610 bitmap_or((ulong *)eoi_exit_bitmap,
10611 vcpu->arch.ioapic_handled_vectors,
10612 to_hv_synic(vcpu)->vec_bitmap, 256);
10613 kvm_x86_call(load_eoi_exitmap)(vcpu, eoi_exit_bitmap);
10614 return;
10615 }
10616 #endif
10617 kvm_x86_call(load_eoi_exitmap)(
10618 vcpu, (u64 *)vcpu->arch.ioapic_handled_vectors);
10619 }
10620
kvm_arch_guest_memory_reclaimed(struct kvm * kvm)10621 void kvm_arch_guest_memory_reclaimed(struct kvm *kvm)
10622 {
10623 kvm_x86_call(guest_memory_reclaimed)(kvm);
10624 }
10625
kvm_vcpu_reload_apic_access_page(struct kvm_vcpu * vcpu)10626 static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
10627 {
10628 if (!lapic_in_kernel(vcpu))
10629 return;
10630
10631 kvm_x86_call(set_apic_access_page_addr)(vcpu);
10632 }
10633
10634 /*
10635 * Called within kvm->srcu read side.
10636 * Returns 1 to let vcpu_run() continue the guest execution loop without
10637 * exiting to the userspace. Otherwise, the value will be returned to the
10638 * userspace.
10639 */
vcpu_enter_guest(struct kvm_vcpu * vcpu)10640 static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
10641 {
10642 int r;
10643 bool req_int_win =
10644 dm_request_for_irq_injection(vcpu) &&
10645 kvm_cpu_accept_dm_intr(vcpu);
10646 fastpath_t exit_fastpath;
10647 u64 run_flags, debug_ctl;
10648
10649 bool req_immediate_exit = false;
10650
10651 if (kvm_request_pending(vcpu)) {
10652 if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu)) {
10653 r = -EIO;
10654 goto out;
10655 }
10656
10657 if (kvm_dirty_ring_check_request(vcpu)) {
10658 r = 0;
10659 goto out;
10660 }
10661
10662 if (kvm_check_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu)) {
10663 if (unlikely(!kvm_x86_ops.nested_ops->get_nested_state_pages(vcpu))) {
10664 r = 0;
10665 goto out;
10666 }
10667 }
10668 if (kvm_check_request(KVM_REQ_MMU_FREE_OBSOLETE_ROOTS, vcpu))
10669 kvm_mmu_free_obsolete_roots(vcpu);
10670 if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu))
10671 __kvm_migrate_timers(vcpu);
10672 if (kvm_check_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu))
10673 kvm_update_masterclock(vcpu->kvm);
10674 if (kvm_check_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu))
10675 kvm_gen_kvmclock_update(vcpu);
10676 if (kvm_check_request(KVM_REQ_CLOCK_UPDATE, vcpu)) {
10677 r = kvm_guest_time_update(vcpu);
10678 if (unlikely(r))
10679 goto out;
10680 }
10681 if (kvm_check_request(KVM_REQ_MMU_SYNC, vcpu))
10682 kvm_mmu_sync_roots(vcpu);
10683 if (kvm_check_request(KVM_REQ_LOAD_MMU_PGD, vcpu))
10684 kvm_mmu_load_pgd(vcpu);
10685
10686 /*
10687 * Note, the order matters here, as flushing "all" TLB entries
10688 * also flushes the "current" TLB entries, i.e. servicing the
10689 * flush "all" will clear any request to flush "current".
10690 */
10691 if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
10692 kvm_vcpu_flush_tlb_all(vcpu);
10693
10694 kvm_service_local_tlb_flush_requests(vcpu);
10695
10696 /*
10697 * Fall back to a "full" guest flush if Hyper-V's precise
10698 * flushing fails. Note, Hyper-V's flushing is per-vCPU, but
10699 * the flushes are considered "remote" and not "local" because
10700 * the requests can be initiated from other vCPUs.
10701 */
10702 #ifdef CONFIG_KVM_HYPERV
10703 if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu) &&
10704 kvm_hv_vcpu_flush_tlb(vcpu))
10705 kvm_vcpu_flush_tlb_guest(vcpu);
10706 #endif
10707
10708 if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) {
10709 vcpu->run->exit_reason = KVM_EXIT_TPR_ACCESS;
10710 r = 0;
10711 goto out;
10712 }
10713 if (kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu)) {
10714 if (is_guest_mode(vcpu))
10715 kvm_x86_ops.nested_ops->triple_fault(vcpu);
10716
10717 if (kvm_check_request(KVM_REQ_TRIPLE_FAULT, vcpu)) {
10718 vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN;
10719 vcpu->mmio_needed = 0;
10720 r = 0;
10721 goto out;
10722 }
10723 }
10724 if (kvm_check_request(KVM_REQ_APF_HALT, vcpu)) {
10725 /* Page is swapped out. Do synthetic halt */
10726 vcpu->arch.apf.halted = true;
10727 r = 1;
10728 goto out;
10729 }
10730 if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu))
10731 record_steal_time(vcpu);
10732 if (kvm_check_request(KVM_REQ_PMU, vcpu))
10733 kvm_pmu_handle_event(vcpu);
10734 if (kvm_check_request(KVM_REQ_PMI, vcpu))
10735 kvm_pmu_deliver_pmi(vcpu);
10736 #ifdef CONFIG_KVM_SMM
10737 if (kvm_check_request(KVM_REQ_SMI, vcpu))
10738 process_smi(vcpu);
10739 #endif
10740 if (kvm_check_request(KVM_REQ_NMI, vcpu))
10741 process_nmi(vcpu);
10742 if (kvm_check_request(KVM_REQ_IOAPIC_EOI_EXIT, vcpu)) {
10743 BUG_ON(vcpu->arch.pending_ioapic_eoi > 255);
10744 if (test_bit(vcpu->arch.pending_ioapic_eoi,
10745 vcpu->arch.ioapic_handled_vectors)) {
10746 vcpu->run->exit_reason = KVM_EXIT_IOAPIC_EOI;
10747 vcpu->run->eoi.vector =
10748 vcpu->arch.pending_ioapic_eoi;
10749 r = 0;
10750 goto out;
10751 }
10752 }
10753 if (kvm_check_request(KVM_REQ_SCAN_IOAPIC, vcpu))
10754 vcpu_scan_ioapic(vcpu);
10755 if (kvm_check_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu))
10756 vcpu_load_eoi_exitmap(vcpu);
10757 if (kvm_check_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu))
10758 kvm_vcpu_reload_apic_access_page(vcpu);
10759 #ifdef CONFIG_KVM_HYPERV
10760 if (kvm_check_request(KVM_REQ_HV_CRASH, vcpu)) {
10761 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
10762 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_CRASH;
10763 vcpu->run->system_event.ndata = 0;
10764 r = 0;
10765 goto out;
10766 }
10767 if (kvm_check_request(KVM_REQ_HV_RESET, vcpu)) {
10768 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
10769 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_RESET;
10770 vcpu->run->system_event.ndata = 0;
10771 r = 0;
10772 goto out;
10773 }
10774 if (kvm_check_request(KVM_REQ_HV_EXIT, vcpu)) {
10775 struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
10776
10777 vcpu->run->exit_reason = KVM_EXIT_HYPERV;
10778 vcpu->run->hyperv = hv_vcpu->exit;
10779 r = 0;
10780 goto out;
10781 }
10782
10783 /*
10784 * KVM_REQ_HV_STIMER has to be processed after
10785 * KVM_REQ_CLOCK_UPDATE, because Hyper-V SynIC timers
10786 * depend on the guest clock being up-to-date
10787 */
10788 if (kvm_check_request(KVM_REQ_HV_STIMER, vcpu))
10789 kvm_hv_process_stimers(vcpu);
10790 #endif
10791 if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu))
10792 kvm_vcpu_update_apicv(vcpu);
10793 if (kvm_check_request(KVM_REQ_APF_READY, vcpu))
10794 kvm_check_async_pf_completion(vcpu);
10795
10796 /*
10797 * Recalc MSR intercepts as userspace may want to intercept
10798 * accesses to MSRs that KVM would otherwise pass through to
10799 * the guest.
10800 */
10801 if (kvm_check_request(KVM_REQ_MSR_FILTER_CHANGED, vcpu))
10802 kvm_x86_call(recalc_msr_intercepts)(vcpu);
10803
10804 if (kvm_check_request(KVM_REQ_UPDATE_CPU_DIRTY_LOGGING, vcpu))
10805 kvm_x86_call(update_cpu_dirty_logging)(vcpu);
10806
10807 if (kvm_check_request(KVM_REQ_UPDATE_PROTECTED_GUEST_STATE, vcpu)) {
10808 kvm_vcpu_reset(vcpu, true);
10809 if (vcpu->arch.mp_state != KVM_MP_STATE_RUNNABLE) {
10810 r = 1;
10811 goto out;
10812 }
10813 }
10814 }
10815
10816 if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win ||
10817 kvm_xen_has_interrupt(vcpu)) {
10818 ++vcpu->stat.req_event;
10819 r = kvm_apic_accept_events(vcpu);
10820 if (r < 0) {
10821 r = 0;
10822 goto out;
10823 }
10824 if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
10825 r = 1;
10826 goto out;
10827 }
10828
10829 r = kvm_check_and_inject_events(vcpu, &req_immediate_exit);
10830 if (r < 0) {
10831 r = 0;
10832 goto out;
10833 }
10834 if (req_int_win)
10835 kvm_x86_call(enable_irq_window)(vcpu);
10836
10837 if (kvm_lapic_enabled(vcpu)) {
10838 update_cr8_intercept(vcpu);
10839 kvm_lapic_sync_to_vapic(vcpu);
10840 }
10841 }
10842
10843 r = kvm_mmu_reload(vcpu);
10844 if (unlikely(r)) {
10845 goto cancel_injection;
10846 }
10847
10848 preempt_disable();
10849
10850 kvm_x86_call(prepare_switch_to_guest)(vcpu);
10851
10852 /*
10853 * Disable IRQs before setting IN_GUEST_MODE. Posted interrupt
10854 * IPI are then delayed after guest entry, which ensures that they
10855 * result in virtual interrupt delivery.
10856 */
10857 local_irq_disable();
10858
10859 /* Store vcpu->apicv_active before vcpu->mode. */
10860 smp_store_release(&vcpu->mode, IN_GUEST_MODE);
10861
10862 kvm_vcpu_srcu_read_unlock(vcpu);
10863
10864 /*
10865 * 1) We should set ->mode before checking ->requests. Please see
10866 * the comment in kvm_vcpu_exiting_guest_mode().
10867 *
10868 * 2) For APICv, we should set ->mode before checking PID.ON. This
10869 * pairs with the memory barrier implicit in pi_test_and_set_on
10870 * (see vmx_deliver_posted_interrupt).
10871 *
10872 * 3) This also orders the write to mode from any reads to the page
10873 * tables done while the VCPU is running. Please see the comment
10874 * in kvm_flush_remote_tlbs.
10875 */
10876 smp_mb__after_srcu_read_unlock();
10877
10878 /*
10879 * Process pending posted interrupts to handle the case where the
10880 * notification IRQ arrived in the host, or was never sent (because the
10881 * target vCPU wasn't running). Do this regardless of the vCPU's APICv
10882 * status, KVM doesn't update assigned devices when APICv is inhibited,
10883 * i.e. they can post interrupts even if APICv is temporarily disabled.
10884 */
10885 if (kvm_lapic_enabled(vcpu))
10886 kvm_x86_call(sync_pir_to_irr)(vcpu);
10887
10888 if (kvm_vcpu_exit_request(vcpu)) {
10889 vcpu->mode = OUTSIDE_GUEST_MODE;
10890 smp_wmb();
10891 local_irq_enable();
10892 preempt_enable();
10893 kvm_vcpu_srcu_read_lock(vcpu);
10894 r = 1;
10895 goto cancel_injection;
10896 }
10897
10898 run_flags = 0;
10899 if (req_immediate_exit) {
10900 run_flags |= KVM_RUN_FORCE_IMMEDIATE_EXIT;
10901 kvm_make_request(KVM_REQ_EVENT, vcpu);
10902 }
10903
10904 fpregs_assert_state_consistent();
10905 if (test_thread_flag(TIF_NEED_FPU_LOAD))
10906 switch_fpu_return();
10907
10908 if (vcpu->arch.guest_fpu.xfd_err)
10909 wrmsrq(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
10910
10911 if (unlikely(vcpu->arch.switch_db_regs &&
10912 !(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH))) {
10913 set_debugreg(DR7_FIXED_1, 7);
10914 set_debugreg(vcpu->arch.eff_db[0], 0);
10915 set_debugreg(vcpu->arch.eff_db[1], 1);
10916 set_debugreg(vcpu->arch.eff_db[2], 2);
10917 set_debugreg(vcpu->arch.eff_db[3], 3);
10918 /* When KVM_DEBUGREG_WONT_EXIT, dr6 is accessible in guest. */
10919 if (unlikely(vcpu->arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT))
10920 run_flags |= KVM_RUN_LOAD_GUEST_DR6;
10921 } else if (unlikely(hw_breakpoint_active())) {
10922 set_debugreg(DR7_FIXED_1, 7);
10923 }
10924
10925 /*
10926 * Refresh the host DEBUGCTL snapshot after disabling IRQs, as DEBUGCTL
10927 * can be modified in IRQ context, e.g. via SMP function calls. Inform
10928 * vendor code if any host-owned bits were changed, e.g. so that the
10929 * value loaded into hardware while running the guest can be updated.
10930 */
10931 debug_ctl = get_debugctlmsr();
10932 if ((debug_ctl ^ vcpu->arch.host_debugctl) & kvm_x86_ops.HOST_OWNED_DEBUGCTL &&
10933 !vcpu->arch.guest_state_protected)
10934 run_flags |= KVM_RUN_LOAD_DEBUGCTL;
10935 vcpu->arch.host_debugctl = debug_ctl;
10936
10937 guest_timing_enter_irqoff();
10938
10939 for (;;) {
10940 /*
10941 * Assert that vCPU vs. VM APICv state is consistent. An APICv
10942 * update must kick and wait for all vCPUs before toggling the
10943 * per-VM state, and responding vCPUs must wait for the update
10944 * to complete before servicing KVM_REQ_APICV_UPDATE.
10945 */
10946 WARN_ON_ONCE((kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)) &&
10947 (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED));
10948
10949 exit_fastpath = kvm_x86_call(vcpu_run)(vcpu, run_flags);
10950 if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
10951 break;
10952
10953 if (kvm_lapic_enabled(vcpu))
10954 kvm_x86_call(sync_pir_to_irr)(vcpu);
10955
10956 if (unlikely(kvm_vcpu_exit_request(vcpu))) {
10957 exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED;
10958 break;
10959 }
10960
10961 run_flags = 0;
10962
10963 /* Note, VM-Exits that go down the "slow" path are accounted below. */
10964 ++vcpu->stat.exits;
10965 }
10966
10967 /*
10968 * Do this here before restoring debug registers on the host. And
10969 * since we do this before handling the vmexit, a DR access vmexit
10970 * can (a) read the correct value of the debug registers, (b) set
10971 * KVM_DEBUGREG_WONT_EXIT again.
10972 */
10973 if (unlikely(vcpu->arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)) {
10974 WARN_ON(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP);
10975 WARN_ON(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH);
10976 kvm_x86_call(sync_dirty_debug_regs)(vcpu);
10977 kvm_update_dr0123(vcpu);
10978 kvm_update_dr7(vcpu);
10979 }
10980
10981 /*
10982 * If the guest has used debug registers, at least dr7
10983 * will be disabled while returning to the host.
10984 * If we don't have active breakpoints in the host, we don't
10985 * care about the messed up debug address registers. But if
10986 * we have some of them active, restore the old state.
10987 */
10988 if (hw_breakpoint_active())
10989 hw_breakpoint_restore();
10990
10991 vcpu->arch.last_vmentry_cpu = vcpu->cpu;
10992 vcpu->arch.last_guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
10993
10994 vcpu->mode = OUTSIDE_GUEST_MODE;
10995 smp_wmb();
10996
10997 /*
10998 * Sync xfd before calling handle_exit_irqoff() which may
10999 * rely on the fact that guest_fpu::xfd is up-to-date (e.g.
11000 * in #NM irqoff handler).
11001 */
11002 if (vcpu->arch.xfd_no_write_intercept)
11003 fpu_sync_guest_vmexit_xfd_state();
11004
11005 kvm_x86_call(handle_exit_irqoff)(vcpu);
11006
11007 if (vcpu->arch.guest_fpu.xfd_err)
11008 wrmsrq(MSR_IA32_XFD_ERR, 0);
11009
11010 /*
11011 * Consume any pending interrupts, including the possible source of
11012 * VM-Exit on SVM and any ticks that occur between VM-Exit and now.
11013 * An instruction is required after local_irq_enable() to fully unblock
11014 * interrupts on processors that implement an interrupt shadow, the
11015 * stat.exits increment will do nicely.
11016 */
11017 kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ);
11018 local_irq_enable();
11019 ++vcpu->stat.exits;
11020 local_irq_disable();
11021 kvm_after_interrupt(vcpu);
11022
11023 /*
11024 * Wait until after servicing IRQs to account guest time so that any
11025 * ticks that occurred while running the guest are properly accounted
11026 * to the guest. Waiting until IRQs are enabled degrades the accuracy
11027 * of accounting via context tracking, but the loss of accuracy is
11028 * acceptable for all known use cases.
11029 */
11030 guest_timing_exit_irqoff();
11031
11032 local_irq_enable();
11033 preempt_enable();
11034
11035 kvm_vcpu_srcu_read_lock(vcpu);
11036
11037 /*
11038 * Call this to ensure WC buffers in guest are evicted after each VM
11039 * Exit, so that the evicted WC writes can be snooped across all cpus
11040 */
11041 smp_mb__after_srcu_read_lock();
11042
11043 /*
11044 * Profile KVM exit RIPs:
11045 */
11046 if (unlikely(prof_on == KVM_PROFILING &&
11047 !vcpu->arch.guest_state_protected)) {
11048 unsigned long rip = kvm_rip_read(vcpu);
11049 profile_hit(KVM_PROFILING, (void *)rip);
11050 }
11051
11052 if (unlikely(vcpu->arch.tsc_always_catchup))
11053 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
11054
11055 if (vcpu->arch.apic_attention)
11056 kvm_lapic_sync_from_vapic(vcpu);
11057
11058 if (unlikely(exit_fastpath == EXIT_FASTPATH_EXIT_USERSPACE))
11059 return 0;
11060
11061 r = kvm_x86_call(handle_exit)(vcpu, exit_fastpath);
11062 return r;
11063
11064 cancel_injection:
11065 if (req_immediate_exit)
11066 kvm_make_request(KVM_REQ_EVENT, vcpu);
11067 kvm_x86_call(cancel_injection)(vcpu);
11068 if (unlikely(vcpu->arch.apic_attention))
11069 kvm_lapic_sync_from_vapic(vcpu);
11070 out:
11071 return r;
11072 }
11073
kvm_vcpu_running(struct kvm_vcpu * vcpu)11074 static bool kvm_vcpu_running(struct kvm_vcpu *vcpu)
11075 {
11076 return (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE &&
11077 !vcpu->arch.apf.halted);
11078 }
11079
kvm_vcpu_has_events(struct kvm_vcpu * vcpu)11080 bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu)
11081 {
11082 if (!list_empty_careful(&vcpu->async_pf.done))
11083 return true;
11084
11085 if (kvm_apic_has_pending_init_or_sipi(vcpu) &&
11086 kvm_apic_init_sipi_allowed(vcpu))
11087 return true;
11088
11089 if (kvm_is_exception_pending(vcpu))
11090 return true;
11091
11092 if (kvm_test_request(KVM_REQ_NMI, vcpu) ||
11093 (vcpu->arch.nmi_pending &&
11094 kvm_x86_call(nmi_allowed)(vcpu, false)))
11095 return true;
11096
11097 #ifdef CONFIG_KVM_SMM
11098 if (kvm_test_request(KVM_REQ_SMI, vcpu) ||
11099 (vcpu->arch.smi_pending &&
11100 kvm_x86_call(smi_allowed)(vcpu, false)))
11101 return true;
11102 #endif
11103
11104 if (kvm_test_request(KVM_REQ_PMI, vcpu))
11105 return true;
11106
11107 if (kvm_test_request(KVM_REQ_UPDATE_PROTECTED_GUEST_STATE, vcpu))
11108 return true;
11109
11110 if (kvm_arch_interrupt_allowed(vcpu) && kvm_cpu_has_interrupt(vcpu))
11111 return true;
11112
11113 if (kvm_hv_has_stimer_pending(vcpu))
11114 return true;
11115
11116 if (is_guest_mode(vcpu) &&
11117 kvm_x86_ops.nested_ops->has_events &&
11118 kvm_x86_ops.nested_ops->has_events(vcpu, false))
11119 return true;
11120
11121 if (kvm_xen_has_pending_events(vcpu))
11122 return true;
11123
11124 return false;
11125 }
11126 EXPORT_SYMBOL_GPL(kvm_vcpu_has_events);
11127
kvm_arch_vcpu_runnable(struct kvm_vcpu * vcpu)11128 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
11129 {
11130 return kvm_vcpu_running(vcpu) || vcpu->arch.pv.pv_unhalted ||
11131 kvm_vcpu_has_events(vcpu);
11132 }
11133
11134 /* Called within kvm->srcu read side. */
vcpu_block(struct kvm_vcpu * vcpu)11135 static inline int vcpu_block(struct kvm_vcpu *vcpu)
11136 {
11137 bool hv_timer;
11138
11139 if (!kvm_arch_vcpu_runnable(vcpu)) {
11140 /*
11141 * Switch to the software timer before halt-polling/blocking as
11142 * the guest's timer may be a break event for the vCPU, and the
11143 * hypervisor timer runs only when the CPU is in guest mode.
11144 * Switch before halt-polling so that KVM recognizes an expired
11145 * timer before blocking.
11146 */
11147 hv_timer = kvm_lapic_hv_timer_in_use(vcpu);
11148 if (hv_timer)
11149 kvm_lapic_switch_to_sw_timer(vcpu);
11150
11151 kvm_vcpu_srcu_read_unlock(vcpu);
11152 if (vcpu->arch.mp_state == KVM_MP_STATE_HALTED)
11153 kvm_vcpu_halt(vcpu);
11154 else
11155 kvm_vcpu_block(vcpu);
11156 kvm_vcpu_srcu_read_lock(vcpu);
11157
11158 if (hv_timer)
11159 kvm_lapic_switch_to_hv_timer(vcpu);
11160
11161 /*
11162 * If the vCPU is not runnable, a signal or another host event
11163 * of some kind is pending; service it without changing the
11164 * vCPU's activity state.
11165 */
11166 if (!kvm_arch_vcpu_runnable(vcpu))
11167 return 1;
11168 }
11169
11170 /*
11171 * Evaluate nested events before exiting the halted state. This allows
11172 * the halt state to be recorded properly in the VMCS12's activity
11173 * state field (AMD does not have a similar field and a VM-Exit always
11174 * causes a spurious wakeup from HLT).
11175 */
11176 if (is_guest_mode(vcpu)) {
11177 int r = kvm_check_nested_events(vcpu);
11178
11179 WARN_ON_ONCE(r == -EBUSY);
11180 if (r < 0)
11181 return 0;
11182 }
11183
11184 if (kvm_apic_accept_events(vcpu) < 0)
11185 return 0;
11186 switch(vcpu->arch.mp_state) {
11187 case KVM_MP_STATE_HALTED:
11188 case KVM_MP_STATE_AP_RESET_HOLD:
11189 kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
11190 fallthrough;
11191 case KVM_MP_STATE_RUNNABLE:
11192 vcpu->arch.apf.halted = false;
11193 break;
11194 case KVM_MP_STATE_INIT_RECEIVED:
11195 break;
11196 default:
11197 WARN_ON_ONCE(1);
11198 break;
11199 }
11200 return 1;
11201 }
11202
11203 /* Called within kvm->srcu read side. */
vcpu_run(struct kvm_vcpu * vcpu)11204 static int vcpu_run(struct kvm_vcpu *vcpu)
11205 {
11206 int r;
11207
11208 vcpu->run->exit_reason = KVM_EXIT_UNKNOWN;
11209
11210 for (;;) {
11211 /*
11212 * If another guest vCPU requests a PV TLB flush in the middle
11213 * of instruction emulation, the rest of the emulation could
11214 * use a stale page translation. Assume that any code after
11215 * this point can start executing an instruction.
11216 */
11217 vcpu->arch.at_instruction_boundary = false;
11218 if (kvm_vcpu_running(vcpu)) {
11219 r = vcpu_enter_guest(vcpu);
11220 } else {
11221 r = vcpu_block(vcpu);
11222 }
11223
11224 if (r <= 0)
11225 break;
11226
11227 kvm_clear_request(KVM_REQ_UNBLOCK, vcpu);
11228 if (kvm_xen_has_pending_events(vcpu))
11229 kvm_xen_inject_pending_events(vcpu);
11230
11231 if (kvm_cpu_has_pending_timer(vcpu))
11232 kvm_inject_pending_timer_irqs(vcpu);
11233
11234 if (dm_request_for_irq_injection(vcpu) &&
11235 kvm_vcpu_ready_for_interrupt_injection(vcpu)) {
11236 r = 0;
11237 vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
11238 ++vcpu->stat.request_irq_exits;
11239 break;
11240 }
11241
11242 if (__xfer_to_guest_mode_work_pending()) {
11243 kvm_vcpu_srcu_read_unlock(vcpu);
11244 r = xfer_to_guest_mode_handle_work(vcpu);
11245 kvm_vcpu_srcu_read_lock(vcpu);
11246 if (r)
11247 return r;
11248 }
11249 }
11250
11251 return r;
11252 }
11253
__kvm_emulate_halt(struct kvm_vcpu * vcpu,int state,int reason)11254 static int __kvm_emulate_halt(struct kvm_vcpu *vcpu, int state, int reason)
11255 {
11256 /*
11257 * The vCPU has halted, e.g. executed HLT. Update the run state if the
11258 * local APIC is in-kernel, the run loop will detect the non-runnable
11259 * state and halt the vCPU. Exit to userspace if the local APIC is
11260 * managed by userspace, in which case userspace is responsible for
11261 * handling wake events.
11262 */
11263 ++vcpu->stat.halt_exits;
11264 if (lapic_in_kernel(vcpu)) {
11265 if (kvm_vcpu_has_events(vcpu) || vcpu->arch.pv.pv_unhalted)
11266 state = KVM_MP_STATE_RUNNABLE;
11267 kvm_set_mp_state(vcpu, state);
11268 return 1;
11269 } else {
11270 vcpu->run->exit_reason = reason;
11271 return 0;
11272 }
11273 }
11274
kvm_emulate_halt_noskip(struct kvm_vcpu * vcpu)11275 int kvm_emulate_halt_noskip(struct kvm_vcpu *vcpu)
11276 {
11277 return __kvm_emulate_halt(vcpu, KVM_MP_STATE_HALTED, KVM_EXIT_HLT);
11278 }
11279 EXPORT_SYMBOL_GPL(kvm_emulate_halt_noskip);
11280
kvm_emulate_halt(struct kvm_vcpu * vcpu)11281 int kvm_emulate_halt(struct kvm_vcpu *vcpu)
11282 {
11283 int ret = kvm_skip_emulated_instruction(vcpu);
11284 /*
11285 * TODO: we might be squashing a GUESTDBG_SINGLESTEP-triggered
11286 * KVM_EXIT_DEBUG here.
11287 */
11288 return kvm_emulate_halt_noskip(vcpu) && ret;
11289 }
11290 EXPORT_SYMBOL_GPL(kvm_emulate_halt);
11291
handle_fastpath_hlt(struct kvm_vcpu * vcpu)11292 fastpath_t handle_fastpath_hlt(struct kvm_vcpu *vcpu)
11293 {
11294 int ret;
11295
11296 kvm_vcpu_srcu_read_lock(vcpu);
11297 ret = kvm_emulate_halt(vcpu);
11298 kvm_vcpu_srcu_read_unlock(vcpu);
11299
11300 if (!ret)
11301 return EXIT_FASTPATH_EXIT_USERSPACE;
11302
11303 if (kvm_vcpu_running(vcpu))
11304 return EXIT_FASTPATH_REENTER_GUEST;
11305
11306 return EXIT_FASTPATH_EXIT_HANDLED;
11307 }
11308 EXPORT_SYMBOL_GPL(handle_fastpath_hlt);
11309
kvm_emulate_ap_reset_hold(struct kvm_vcpu * vcpu)11310 int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu)
11311 {
11312 int ret = kvm_skip_emulated_instruction(vcpu);
11313
11314 return __kvm_emulate_halt(vcpu, KVM_MP_STATE_AP_RESET_HOLD,
11315 KVM_EXIT_AP_RESET_HOLD) && ret;
11316 }
11317 EXPORT_SYMBOL_GPL(kvm_emulate_ap_reset_hold);
11318
kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu * vcpu)11319 bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu)
11320 {
11321 return kvm_vcpu_apicv_active(vcpu) &&
11322 kvm_x86_call(dy_apicv_has_pending_interrupt)(vcpu);
11323 }
11324
kvm_arch_vcpu_preempted_in_kernel(struct kvm_vcpu * vcpu)11325 bool kvm_arch_vcpu_preempted_in_kernel(struct kvm_vcpu *vcpu)
11326 {
11327 return vcpu->arch.preempted_in_kernel;
11328 }
11329
kvm_arch_dy_runnable(struct kvm_vcpu * vcpu)11330 bool kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
11331 {
11332 if (READ_ONCE(vcpu->arch.pv.pv_unhalted))
11333 return true;
11334
11335 if (kvm_test_request(KVM_REQ_NMI, vcpu) ||
11336 #ifdef CONFIG_KVM_SMM
11337 kvm_test_request(KVM_REQ_SMI, vcpu) ||
11338 #endif
11339 kvm_test_request(KVM_REQ_EVENT, vcpu))
11340 return true;
11341
11342 return kvm_arch_dy_has_pending_interrupt(vcpu);
11343 }
11344
complete_emulated_io(struct kvm_vcpu * vcpu)11345 static inline int complete_emulated_io(struct kvm_vcpu *vcpu)
11346 {
11347 return kvm_emulate_instruction(vcpu, EMULTYPE_NO_DECODE);
11348 }
11349
complete_emulated_pio(struct kvm_vcpu * vcpu)11350 static int complete_emulated_pio(struct kvm_vcpu *vcpu)
11351 {
11352 BUG_ON(!vcpu->arch.pio.count);
11353
11354 return complete_emulated_io(vcpu);
11355 }
11356
11357 /*
11358 * Implements the following, as a state machine:
11359 *
11360 * read:
11361 * for each fragment
11362 * for each mmio piece in the fragment
11363 * write gpa, len
11364 * exit
11365 * copy data
11366 * execute insn
11367 *
11368 * write:
11369 * for each fragment
11370 * for each mmio piece in the fragment
11371 * write gpa, len
11372 * copy data
11373 * exit
11374 */
complete_emulated_mmio(struct kvm_vcpu * vcpu)11375 static int complete_emulated_mmio(struct kvm_vcpu *vcpu)
11376 {
11377 struct kvm_run *run = vcpu->run;
11378 struct kvm_mmio_fragment *frag;
11379 unsigned len;
11380
11381 BUG_ON(!vcpu->mmio_needed);
11382
11383 /* Complete previous fragment */
11384 frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment];
11385 len = min(8u, frag->len);
11386 if (!vcpu->mmio_is_write)
11387 memcpy(frag->data, run->mmio.data, len);
11388
11389 if (frag->len <= 8) {
11390 /* Switch to the next fragment. */
11391 frag++;
11392 vcpu->mmio_cur_fragment++;
11393 } else {
11394 /* Go forward to the next mmio piece. */
11395 frag->data += len;
11396 frag->gpa += len;
11397 frag->len -= len;
11398 }
11399
11400 if (vcpu->mmio_cur_fragment >= vcpu->mmio_nr_fragments) {
11401 vcpu->mmio_needed = 0;
11402
11403 /* FIXME: return into emulator if single-stepping. */
11404 if (vcpu->mmio_is_write)
11405 return 1;
11406 vcpu->mmio_read_completed = 1;
11407 return complete_emulated_io(vcpu);
11408 }
11409
11410 run->exit_reason = KVM_EXIT_MMIO;
11411 run->mmio.phys_addr = frag->gpa;
11412 if (vcpu->mmio_is_write)
11413 memcpy(run->mmio.data, frag->data, min(8u, frag->len));
11414 run->mmio.len = min(8u, frag->len);
11415 run->mmio.is_write = vcpu->mmio_is_write;
11416 vcpu->arch.complete_userspace_io = complete_emulated_mmio;
11417 return 0;
11418 }
11419
11420 /* Swap (qemu) user FPU context for the guest FPU context. */
kvm_load_guest_fpu(struct kvm_vcpu * vcpu)11421 static void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
11422 {
11423 /* Exclude PKRU, it's restored separately immediately after VM-Exit. */
11424 fpu_swap_kvm_fpstate(&vcpu->arch.guest_fpu, true);
11425 trace_kvm_fpu(1);
11426 }
11427
11428 /* When vcpu_run ends, restore user space FPU context. */
kvm_put_guest_fpu(struct kvm_vcpu * vcpu)11429 static void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
11430 {
11431 fpu_swap_kvm_fpstate(&vcpu->arch.guest_fpu, false);
11432 ++vcpu->stat.fpu_reload;
11433 trace_kvm_fpu(0);
11434 }
11435
kvm_x86_vcpu_pre_run(struct kvm_vcpu * vcpu)11436 static int kvm_x86_vcpu_pre_run(struct kvm_vcpu *vcpu)
11437 {
11438 /*
11439 * SIPI_RECEIVED is obsolete; KVM leaves the vCPU in Wait-For-SIPI and
11440 * tracks the pending SIPI separately. SIPI_RECEIVED is still accepted
11441 * by KVM_SET_VCPU_EVENTS for backwards compatibility, but should be
11442 * converted to INIT_RECEIVED.
11443 */
11444 if (WARN_ON_ONCE(vcpu->arch.mp_state == KVM_MP_STATE_SIPI_RECEIVED))
11445 return -EINVAL;
11446
11447 /*
11448 * Disallow running the vCPU if userspace forced it into an impossible
11449 * MP_STATE, e.g. if the vCPU is in WFS but SIPI is blocked.
11450 */
11451 if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED &&
11452 !kvm_apic_init_sipi_allowed(vcpu))
11453 return -EINVAL;
11454
11455 return kvm_x86_call(vcpu_pre_run)(vcpu);
11456 }
11457
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)11458 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
11459 {
11460 struct kvm_queued_exception *ex = &vcpu->arch.exception;
11461 struct kvm_run *kvm_run = vcpu->run;
11462 u64 sync_valid_fields;
11463 int r;
11464
11465 r = kvm_mmu_post_init_vm(vcpu->kvm);
11466 if (r)
11467 return r;
11468
11469 vcpu_load(vcpu);
11470 kvm_sigset_activate(vcpu);
11471 kvm_run->flags = 0;
11472 kvm_load_guest_fpu(vcpu);
11473
11474 kvm_vcpu_srcu_read_lock(vcpu);
11475 if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
11476 if (!vcpu->wants_to_run) {
11477 r = -EINTR;
11478 goto out;
11479 }
11480
11481 /*
11482 * Don't bother switching APIC timer emulation from the
11483 * hypervisor timer to the software timer, the only way for the
11484 * APIC timer to be active is if userspace stuffed vCPU state,
11485 * i.e. put the vCPU into a nonsensical state. Only an INIT
11486 * will transition the vCPU out of UNINITIALIZED (without more
11487 * state stuffing from userspace), which will reset the local
11488 * APIC and thus cancel the timer or drop the IRQ (if the timer
11489 * already expired).
11490 */
11491 kvm_vcpu_srcu_read_unlock(vcpu);
11492 kvm_vcpu_block(vcpu);
11493 kvm_vcpu_srcu_read_lock(vcpu);
11494
11495 if (kvm_apic_accept_events(vcpu) < 0) {
11496 r = 0;
11497 goto out;
11498 }
11499 r = -EAGAIN;
11500 if (signal_pending(current)) {
11501 r = -EINTR;
11502 kvm_run->exit_reason = KVM_EXIT_INTR;
11503 ++vcpu->stat.signal_exits;
11504 }
11505 goto out;
11506 }
11507
11508 sync_valid_fields = kvm_sync_valid_fields(vcpu->kvm);
11509 if ((kvm_run->kvm_valid_regs & ~sync_valid_fields) ||
11510 (kvm_run->kvm_dirty_regs & ~sync_valid_fields)) {
11511 r = -EINVAL;
11512 goto out;
11513 }
11514
11515 if (kvm_run->kvm_dirty_regs) {
11516 r = sync_regs(vcpu);
11517 if (r != 0)
11518 goto out;
11519 }
11520
11521 /* re-sync apic's tpr */
11522 if (!lapic_in_kernel(vcpu)) {
11523 if (kvm_set_cr8(vcpu, kvm_run->cr8) != 0) {
11524 r = -EINVAL;
11525 goto out;
11526 }
11527 }
11528
11529 /*
11530 * If userspace set a pending exception and L2 is active, convert it to
11531 * a pending VM-Exit if L1 wants to intercept the exception.
11532 */
11533 if (vcpu->arch.exception_from_userspace && is_guest_mode(vcpu) &&
11534 kvm_x86_ops.nested_ops->is_exception_vmexit(vcpu, ex->vector,
11535 ex->error_code)) {
11536 kvm_queue_exception_vmexit(vcpu, ex->vector,
11537 ex->has_error_code, ex->error_code,
11538 ex->has_payload, ex->payload);
11539 ex->injected = false;
11540 ex->pending = false;
11541 }
11542 vcpu->arch.exception_from_userspace = false;
11543
11544 if (unlikely(vcpu->arch.complete_userspace_io)) {
11545 int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io;
11546 vcpu->arch.complete_userspace_io = NULL;
11547 r = cui(vcpu);
11548 if (r <= 0)
11549 goto out;
11550 } else {
11551 WARN_ON_ONCE(vcpu->arch.pio.count);
11552 WARN_ON_ONCE(vcpu->mmio_needed);
11553 }
11554
11555 if (!vcpu->wants_to_run) {
11556 r = -EINTR;
11557 goto out;
11558 }
11559
11560 r = kvm_x86_vcpu_pre_run(vcpu);
11561 if (r <= 0)
11562 goto out;
11563
11564 r = vcpu_run(vcpu);
11565
11566 out:
11567 kvm_put_guest_fpu(vcpu);
11568 if (kvm_run->kvm_valid_regs && likely(!vcpu->arch.guest_state_protected))
11569 store_regs(vcpu);
11570 post_kvm_run_save(vcpu);
11571 kvm_vcpu_srcu_read_unlock(vcpu);
11572
11573 kvm_sigset_deactivate(vcpu);
11574 vcpu_put(vcpu);
11575 return r;
11576 }
11577
__get_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11578 static void __get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11579 {
11580 if (vcpu->arch.emulate_regs_need_sync_to_vcpu) {
11581 /*
11582 * We are here if userspace calls get_regs() in the middle of
11583 * instruction emulation. Registers state needs to be copied
11584 * back from emulation context to vcpu. Userspace shouldn't do
11585 * that usually, but some bad designed PV devices (vmware
11586 * backdoor interface) need this to work
11587 */
11588 emulator_writeback_register_cache(vcpu->arch.emulate_ctxt);
11589 vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
11590 }
11591 regs->rax = kvm_rax_read(vcpu);
11592 regs->rbx = kvm_rbx_read(vcpu);
11593 regs->rcx = kvm_rcx_read(vcpu);
11594 regs->rdx = kvm_rdx_read(vcpu);
11595 regs->rsi = kvm_rsi_read(vcpu);
11596 regs->rdi = kvm_rdi_read(vcpu);
11597 regs->rsp = kvm_rsp_read(vcpu);
11598 regs->rbp = kvm_rbp_read(vcpu);
11599 #ifdef CONFIG_X86_64
11600 regs->r8 = kvm_r8_read(vcpu);
11601 regs->r9 = kvm_r9_read(vcpu);
11602 regs->r10 = kvm_r10_read(vcpu);
11603 regs->r11 = kvm_r11_read(vcpu);
11604 regs->r12 = kvm_r12_read(vcpu);
11605 regs->r13 = kvm_r13_read(vcpu);
11606 regs->r14 = kvm_r14_read(vcpu);
11607 regs->r15 = kvm_r15_read(vcpu);
11608 #endif
11609
11610 regs->rip = kvm_rip_read(vcpu);
11611 regs->rflags = kvm_get_rflags(vcpu);
11612 }
11613
kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11614 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11615 {
11616 if (vcpu->kvm->arch.has_protected_state &&
11617 vcpu->arch.guest_state_protected)
11618 return -EINVAL;
11619
11620 vcpu_load(vcpu);
11621 __get_regs(vcpu, regs);
11622 vcpu_put(vcpu);
11623 return 0;
11624 }
11625
__set_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11626 static void __set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11627 {
11628 vcpu->arch.emulate_regs_need_sync_from_vcpu = true;
11629 vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
11630
11631 kvm_rax_write(vcpu, regs->rax);
11632 kvm_rbx_write(vcpu, regs->rbx);
11633 kvm_rcx_write(vcpu, regs->rcx);
11634 kvm_rdx_write(vcpu, regs->rdx);
11635 kvm_rsi_write(vcpu, regs->rsi);
11636 kvm_rdi_write(vcpu, regs->rdi);
11637 kvm_rsp_write(vcpu, regs->rsp);
11638 kvm_rbp_write(vcpu, regs->rbp);
11639 #ifdef CONFIG_X86_64
11640 kvm_r8_write(vcpu, regs->r8);
11641 kvm_r9_write(vcpu, regs->r9);
11642 kvm_r10_write(vcpu, regs->r10);
11643 kvm_r11_write(vcpu, regs->r11);
11644 kvm_r12_write(vcpu, regs->r12);
11645 kvm_r13_write(vcpu, regs->r13);
11646 kvm_r14_write(vcpu, regs->r14);
11647 kvm_r15_write(vcpu, regs->r15);
11648 #endif
11649
11650 kvm_rip_write(vcpu, regs->rip);
11651 kvm_set_rflags(vcpu, regs->rflags | X86_EFLAGS_FIXED);
11652
11653 vcpu->arch.exception.pending = false;
11654 vcpu->arch.exception_vmexit.pending = false;
11655
11656 kvm_make_request(KVM_REQ_EVENT, vcpu);
11657 }
11658
kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11659 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11660 {
11661 if (vcpu->kvm->arch.has_protected_state &&
11662 vcpu->arch.guest_state_protected)
11663 return -EINVAL;
11664
11665 vcpu_load(vcpu);
11666 __set_regs(vcpu, regs);
11667 vcpu_put(vcpu);
11668 return 0;
11669 }
11670
__get_sregs_common(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11671 static void __get_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11672 {
11673 struct desc_ptr dt;
11674
11675 if (vcpu->arch.guest_state_protected)
11676 goto skip_protected_regs;
11677
11678 kvm_get_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
11679 kvm_get_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
11680 kvm_get_segment(vcpu, &sregs->es, VCPU_SREG_ES);
11681 kvm_get_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
11682 kvm_get_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
11683 kvm_get_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
11684
11685 kvm_get_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
11686 kvm_get_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
11687
11688 kvm_x86_call(get_idt)(vcpu, &dt);
11689 sregs->idt.limit = dt.size;
11690 sregs->idt.base = dt.address;
11691 kvm_x86_call(get_gdt)(vcpu, &dt);
11692 sregs->gdt.limit = dt.size;
11693 sregs->gdt.base = dt.address;
11694
11695 sregs->cr2 = vcpu->arch.cr2;
11696 sregs->cr3 = kvm_read_cr3(vcpu);
11697
11698 skip_protected_regs:
11699 sregs->cr0 = kvm_read_cr0(vcpu);
11700 sregs->cr4 = kvm_read_cr4(vcpu);
11701 sregs->cr8 = kvm_get_cr8(vcpu);
11702 sregs->efer = vcpu->arch.efer;
11703 sregs->apic_base = vcpu->arch.apic_base;
11704 }
11705
__get_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11706 static void __get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11707 {
11708 __get_sregs_common(vcpu, sregs);
11709
11710 if (vcpu->arch.guest_state_protected)
11711 return;
11712
11713 if (vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft)
11714 set_bit(vcpu->arch.interrupt.nr,
11715 (unsigned long *)sregs->interrupt_bitmap);
11716 }
11717
__get_sregs2(struct kvm_vcpu * vcpu,struct kvm_sregs2 * sregs2)11718 static void __get_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2)
11719 {
11720 int i;
11721
11722 __get_sregs_common(vcpu, (struct kvm_sregs *)sregs2);
11723
11724 if (vcpu->arch.guest_state_protected)
11725 return;
11726
11727 if (is_pae_paging(vcpu)) {
11728 for (i = 0 ; i < 4 ; i++)
11729 sregs2->pdptrs[i] = kvm_pdptr_read(vcpu, i);
11730 sregs2->flags |= KVM_SREGS2_FLAGS_PDPTRS_VALID;
11731 }
11732 }
11733
kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11734 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
11735 struct kvm_sregs *sregs)
11736 {
11737 if (vcpu->kvm->arch.has_protected_state &&
11738 vcpu->arch.guest_state_protected)
11739 return -EINVAL;
11740
11741 vcpu_load(vcpu);
11742 __get_sregs(vcpu, sregs);
11743 vcpu_put(vcpu);
11744 return 0;
11745 }
11746
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)11747 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
11748 struct kvm_mp_state *mp_state)
11749 {
11750 int r;
11751
11752 vcpu_load(vcpu);
11753 if (kvm_mpx_supported())
11754 kvm_load_guest_fpu(vcpu);
11755
11756 kvm_vcpu_srcu_read_lock(vcpu);
11757
11758 r = kvm_apic_accept_events(vcpu);
11759 if (r < 0)
11760 goto out;
11761 r = 0;
11762
11763 if ((vcpu->arch.mp_state == KVM_MP_STATE_HALTED ||
11764 vcpu->arch.mp_state == KVM_MP_STATE_AP_RESET_HOLD) &&
11765 vcpu->arch.pv.pv_unhalted)
11766 mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
11767 else
11768 mp_state->mp_state = vcpu->arch.mp_state;
11769
11770 out:
11771 kvm_vcpu_srcu_read_unlock(vcpu);
11772
11773 if (kvm_mpx_supported())
11774 kvm_put_guest_fpu(vcpu);
11775 vcpu_put(vcpu);
11776 return r;
11777 }
11778
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)11779 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
11780 struct kvm_mp_state *mp_state)
11781 {
11782 int ret = -EINVAL;
11783
11784 vcpu_load(vcpu);
11785
11786 switch (mp_state->mp_state) {
11787 case KVM_MP_STATE_UNINITIALIZED:
11788 case KVM_MP_STATE_HALTED:
11789 case KVM_MP_STATE_AP_RESET_HOLD:
11790 case KVM_MP_STATE_INIT_RECEIVED:
11791 case KVM_MP_STATE_SIPI_RECEIVED:
11792 if (!lapic_in_kernel(vcpu))
11793 goto out;
11794 break;
11795
11796 case KVM_MP_STATE_RUNNABLE:
11797 break;
11798
11799 default:
11800 goto out;
11801 }
11802
11803 /*
11804 * SIPI_RECEIVED is obsolete and no longer used internally; KVM instead
11805 * leaves the vCPU in INIT_RECIEVED (Wait-For-SIPI) and pends the SIPI.
11806 * Translate SIPI_RECEIVED as appropriate for backwards compatibility.
11807 */
11808 if (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED) {
11809 mp_state->mp_state = KVM_MP_STATE_INIT_RECEIVED;
11810 set_bit(KVM_APIC_SIPI, &vcpu->arch.apic->pending_events);
11811 }
11812
11813 kvm_set_mp_state(vcpu, mp_state->mp_state);
11814 kvm_make_request(KVM_REQ_EVENT, vcpu);
11815
11816 ret = 0;
11817 out:
11818 vcpu_put(vcpu);
11819 return ret;
11820 }
11821
kvm_task_switch(struct kvm_vcpu * vcpu,u16 tss_selector,int idt_index,int reason,bool has_error_code,u32 error_code)11822 int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index,
11823 int reason, bool has_error_code, u32 error_code)
11824 {
11825 struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
11826 int ret;
11827
11828 init_emulate_ctxt(vcpu);
11829
11830 ret = emulator_task_switch(ctxt, tss_selector, idt_index, reason,
11831 has_error_code, error_code);
11832
11833 /*
11834 * Report an error userspace if MMIO is needed, as KVM doesn't support
11835 * MMIO during a task switch (or any other complex operation).
11836 */
11837 if (ret || vcpu->mmio_needed) {
11838 vcpu->mmio_needed = false;
11839 vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
11840 vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
11841 vcpu->run->internal.ndata = 0;
11842 return 0;
11843 }
11844
11845 kvm_rip_write(vcpu, ctxt->eip);
11846 kvm_set_rflags(vcpu, ctxt->eflags);
11847 return 1;
11848 }
11849 EXPORT_SYMBOL_GPL(kvm_task_switch);
11850
kvm_is_valid_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11851 static bool kvm_is_valid_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11852 {
11853 if ((sregs->efer & EFER_LME) && (sregs->cr0 & X86_CR0_PG)) {
11854 /*
11855 * When EFER.LME and CR0.PG are set, the processor is in
11856 * 64-bit mode (though maybe in a 32-bit code segment).
11857 * CR4.PAE and EFER.LMA must be set.
11858 */
11859 if (!(sregs->cr4 & X86_CR4_PAE) || !(sregs->efer & EFER_LMA))
11860 return false;
11861 if (!kvm_vcpu_is_legal_cr3(vcpu, sregs->cr3))
11862 return false;
11863 } else {
11864 /*
11865 * Not in 64-bit mode: EFER.LMA is clear and the code
11866 * segment cannot be 64-bit.
11867 */
11868 if (sregs->efer & EFER_LMA || sregs->cs.l)
11869 return false;
11870 }
11871
11872 return kvm_is_valid_cr4(vcpu, sregs->cr4) &&
11873 kvm_is_valid_cr0(vcpu, sregs->cr0);
11874 }
11875
__set_sregs_common(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs,int * mmu_reset_needed,bool update_pdptrs)11876 static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs,
11877 int *mmu_reset_needed, bool update_pdptrs)
11878 {
11879 int idx;
11880 struct desc_ptr dt;
11881
11882 if (!kvm_is_valid_sregs(vcpu, sregs))
11883 return -EINVAL;
11884
11885 if (kvm_apic_set_base(vcpu, sregs->apic_base, true))
11886 return -EINVAL;
11887
11888 if (vcpu->arch.guest_state_protected)
11889 return 0;
11890
11891 dt.size = sregs->idt.limit;
11892 dt.address = sregs->idt.base;
11893 kvm_x86_call(set_idt)(vcpu, &dt);
11894 dt.size = sregs->gdt.limit;
11895 dt.address = sregs->gdt.base;
11896 kvm_x86_call(set_gdt)(vcpu, &dt);
11897
11898 vcpu->arch.cr2 = sregs->cr2;
11899 *mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
11900 vcpu->arch.cr3 = sregs->cr3;
11901 kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
11902 kvm_x86_call(post_set_cr3)(vcpu, sregs->cr3);
11903
11904 kvm_set_cr8(vcpu, sregs->cr8);
11905
11906 *mmu_reset_needed |= vcpu->arch.efer != sregs->efer;
11907 kvm_x86_call(set_efer)(vcpu, sregs->efer);
11908
11909 *mmu_reset_needed |= kvm_read_cr0(vcpu) != sregs->cr0;
11910 kvm_x86_call(set_cr0)(vcpu, sregs->cr0);
11911
11912 *mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4;
11913 kvm_x86_call(set_cr4)(vcpu, sregs->cr4);
11914
11915 if (update_pdptrs) {
11916 idx = srcu_read_lock(&vcpu->kvm->srcu);
11917 if (is_pae_paging(vcpu)) {
11918 load_pdptrs(vcpu, kvm_read_cr3(vcpu));
11919 *mmu_reset_needed = 1;
11920 }
11921 srcu_read_unlock(&vcpu->kvm->srcu, idx);
11922 }
11923
11924 kvm_set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
11925 kvm_set_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
11926 kvm_set_segment(vcpu, &sregs->es, VCPU_SREG_ES);
11927 kvm_set_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
11928 kvm_set_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
11929 kvm_set_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
11930
11931 kvm_set_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
11932 kvm_set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
11933
11934 update_cr8_intercept(vcpu);
11935
11936 /* Older userspace won't unhalt the vcpu on reset. */
11937 if (kvm_vcpu_is_bsp(vcpu) && kvm_rip_read(vcpu) == 0xfff0 &&
11938 sregs->cs.selector == 0xf000 && sregs->cs.base == 0xffff0000 &&
11939 !is_protmode(vcpu))
11940 kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
11941
11942 return 0;
11943 }
11944
__set_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11945 static int __set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11946 {
11947 int pending_vec, max_bits;
11948 int mmu_reset_needed = 0;
11949 int ret = __set_sregs_common(vcpu, sregs, &mmu_reset_needed, true);
11950
11951 if (ret)
11952 return ret;
11953
11954 if (mmu_reset_needed) {
11955 kvm_mmu_reset_context(vcpu);
11956 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
11957 }
11958
11959 max_bits = KVM_NR_INTERRUPTS;
11960 pending_vec = find_first_bit(
11961 (const unsigned long *)sregs->interrupt_bitmap, max_bits);
11962
11963 if (pending_vec < max_bits) {
11964 kvm_queue_interrupt(vcpu, pending_vec, false);
11965 pr_debug("Set back pending irq %d\n", pending_vec);
11966 kvm_make_request(KVM_REQ_EVENT, vcpu);
11967 }
11968 return 0;
11969 }
11970
__set_sregs2(struct kvm_vcpu * vcpu,struct kvm_sregs2 * sregs2)11971 static int __set_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2)
11972 {
11973 int mmu_reset_needed = 0;
11974 bool valid_pdptrs = sregs2->flags & KVM_SREGS2_FLAGS_PDPTRS_VALID;
11975 bool pae = (sregs2->cr0 & X86_CR0_PG) && (sregs2->cr4 & X86_CR4_PAE) &&
11976 !(sregs2->efer & EFER_LMA);
11977 int i, ret;
11978
11979 if (sregs2->flags & ~KVM_SREGS2_FLAGS_PDPTRS_VALID)
11980 return -EINVAL;
11981
11982 if (valid_pdptrs && (!pae || vcpu->arch.guest_state_protected))
11983 return -EINVAL;
11984
11985 ret = __set_sregs_common(vcpu, (struct kvm_sregs *)sregs2,
11986 &mmu_reset_needed, !valid_pdptrs);
11987 if (ret)
11988 return ret;
11989
11990 if (valid_pdptrs) {
11991 for (i = 0; i < 4 ; i++)
11992 kvm_pdptr_write(vcpu, i, sregs2->pdptrs[i]);
11993
11994 kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR);
11995 mmu_reset_needed = 1;
11996 vcpu->arch.pdptrs_from_userspace = true;
11997 }
11998 if (mmu_reset_needed) {
11999 kvm_mmu_reset_context(vcpu);
12000 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
12001 }
12002 return 0;
12003 }
12004
kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)12005 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
12006 struct kvm_sregs *sregs)
12007 {
12008 int ret;
12009
12010 if (vcpu->kvm->arch.has_protected_state &&
12011 vcpu->arch.guest_state_protected)
12012 return -EINVAL;
12013
12014 vcpu_load(vcpu);
12015 ret = __set_sregs(vcpu, sregs);
12016 vcpu_put(vcpu);
12017 return ret;
12018 }
12019
kvm_arch_vcpu_guestdbg_update_apicv_inhibit(struct kvm * kvm)12020 static void kvm_arch_vcpu_guestdbg_update_apicv_inhibit(struct kvm *kvm)
12021 {
12022 bool set = false;
12023 struct kvm_vcpu *vcpu;
12024 unsigned long i;
12025
12026 if (!enable_apicv)
12027 return;
12028
12029 down_write(&kvm->arch.apicv_update_lock);
12030
12031 kvm_for_each_vcpu(i, vcpu, kvm) {
12032 if (vcpu->guest_debug & KVM_GUESTDBG_BLOCKIRQ) {
12033 set = true;
12034 break;
12035 }
12036 }
12037 __kvm_set_or_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_BLOCKIRQ, set);
12038 up_write(&kvm->arch.apicv_update_lock);
12039 }
12040
kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu * vcpu,struct kvm_guest_debug * dbg)12041 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
12042 struct kvm_guest_debug *dbg)
12043 {
12044 unsigned long rflags;
12045 int i, r;
12046
12047 if (vcpu->arch.guest_state_protected)
12048 return -EINVAL;
12049
12050 vcpu_load(vcpu);
12051
12052 if (dbg->control & (KVM_GUESTDBG_INJECT_DB | KVM_GUESTDBG_INJECT_BP)) {
12053 r = -EBUSY;
12054 if (kvm_is_exception_pending(vcpu))
12055 goto out;
12056 if (dbg->control & KVM_GUESTDBG_INJECT_DB)
12057 kvm_queue_exception(vcpu, DB_VECTOR);
12058 else
12059 kvm_queue_exception(vcpu, BP_VECTOR);
12060 }
12061
12062 /*
12063 * Read rflags as long as potentially injected trace flags are still
12064 * filtered out.
12065 */
12066 rflags = kvm_get_rflags(vcpu);
12067
12068 vcpu->guest_debug = dbg->control;
12069 if (!(vcpu->guest_debug & KVM_GUESTDBG_ENABLE))
12070 vcpu->guest_debug = 0;
12071
12072 if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) {
12073 for (i = 0; i < KVM_NR_DB_REGS; ++i)
12074 vcpu->arch.eff_db[i] = dbg->arch.debugreg[i];
12075 vcpu->arch.guest_debug_dr7 = dbg->arch.debugreg[7];
12076 } else {
12077 for (i = 0; i < KVM_NR_DB_REGS; i++)
12078 vcpu->arch.eff_db[i] = vcpu->arch.db[i];
12079 }
12080 kvm_update_dr7(vcpu);
12081
12082 if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
12083 vcpu->arch.singlestep_rip = kvm_get_linear_rip(vcpu);
12084
12085 /*
12086 * Trigger an rflags update that will inject or remove the trace
12087 * flags.
12088 */
12089 kvm_set_rflags(vcpu, rflags);
12090
12091 kvm_x86_call(update_exception_bitmap)(vcpu);
12092
12093 kvm_arch_vcpu_guestdbg_update_apicv_inhibit(vcpu->kvm);
12094
12095 r = 0;
12096
12097 out:
12098 vcpu_put(vcpu);
12099 return r;
12100 }
12101
12102 /*
12103 * Translate a guest virtual address to a guest physical address.
12104 */
kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu * vcpu,struct kvm_translation * tr)12105 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
12106 struct kvm_translation *tr)
12107 {
12108 unsigned long vaddr = tr->linear_address;
12109 gpa_t gpa;
12110 int idx;
12111
12112 vcpu_load(vcpu);
12113
12114 idx = srcu_read_lock(&vcpu->kvm->srcu);
12115 gpa = kvm_mmu_gva_to_gpa_system(vcpu, vaddr, NULL);
12116 srcu_read_unlock(&vcpu->kvm->srcu, idx);
12117 tr->physical_address = gpa;
12118 tr->valid = gpa != INVALID_GPA;
12119 tr->writeable = 1;
12120 tr->usermode = 0;
12121
12122 vcpu_put(vcpu);
12123 return 0;
12124 }
12125
kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu * vcpu,struct kvm_fpu * fpu)12126 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
12127 {
12128 struct fxregs_state *fxsave;
12129
12130 if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
12131 return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
12132
12133 vcpu_load(vcpu);
12134
12135 fxsave = &vcpu->arch.guest_fpu.fpstate->regs.fxsave;
12136 memcpy(fpu->fpr, fxsave->st_space, 128);
12137 fpu->fcw = fxsave->cwd;
12138 fpu->fsw = fxsave->swd;
12139 fpu->ftwx = fxsave->twd;
12140 fpu->last_opcode = fxsave->fop;
12141 fpu->last_ip = fxsave->rip;
12142 fpu->last_dp = fxsave->rdp;
12143 memcpy(fpu->xmm, fxsave->xmm_space, sizeof(fxsave->xmm_space));
12144
12145 vcpu_put(vcpu);
12146 return 0;
12147 }
12148
kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu * vcpu,struct kvm_fpu * fpu)12149 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
12150 {
12151 struct fxregs_state *fxsave;
12152
12153 if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
12154 return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
12155
12156 vcpu_load(vcpu);
12157
12158 fxsave = &vcpu->arch.guest_fpu.fpstate->regs.fxsave;
12159
12160 memcpy(fxsave->st_space, fpu->fpr, 128);
12161 fxsave->cwd = fpu->fcw;
12162 fxsave->swd = fpu->fsw;
12163 fxsave->twd = fpu->ftwx;
12164 fxsave->fop = fpu->last_opcode;
12165 fxsave->rip = fpu->last_ip;
12166 fxsave->rdp = fpu->last_dp;
12167 memcpy(fxsave->xmm_space, fpu->xmm, sizeof(fxsave->xmm_space));
12168
12169 vcpu_put(vcpu);
12170 return 0;
12171 }
12172
store_regs(struct kvm_vcpu * vcpu)12173 static void store_regs(struct kvm_vcpu *vcpu)
12174 {
12175 BUILD_BUG_ON(sizeof(struct kvm_sync_regs) > SYNC_REGS_SIZE_BYTES);
12176
12177 if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_REGS)
12178 __get_regs(vcpu, &vcpu->run->s.regs.regs);
12179
12180 if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_SREGS)
12181 __get_sregs(vcpu, &vcpu->run->s.regs.sregs);
12182
12183 if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_EVENTS)
12184 kvm_vcpu_ioctl_x86_get_vcpu_events(
12185 vcpu, &vcpu->run->s.regs.events);
12186 }
12187
sync_regs(struct kvm_vcpu * vcpu)12188 static int sync_regs(struct kvm_vcpu *vcpu)
12189 {
12190 if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_REGS) {
12191 __set_regs(vcpu, &vcpu->run->s.regs.regs);
12192 vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_REGS;
12193 }
12194
12195 if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_SREGS) {
12196 struct kvm_sregs sregs = vcpu->run->s.regs.sregs;
12197
12198 if (__set_sregs(vcpu, &sregs))
12199 return -EINVAL;
12200
12201 vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_SREGS;
12202 }
12203
12204 if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_EVENTS) {
12205 struct kvm_vcpu_events events = vcpu->run->s.regs.events;
12206
12207 if (kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events))
12208 return -EINVAL;
12209
12210 vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_EVENTS;
12211 }
12212
12213 return 0;
12214 }
12215
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)12216 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
12217 {
12218 if (kvm_check_tsc_unstable() && kvm->created_vcpus)
12219 pr_warn_once("SMP vm created on host with unstable TSC; "
12220 "guest TSC will not be reliable\n");
12221
12222 if (!kvm->arch.max_vcpu_ids)
12223 kvm->arch.max_vcpu_ids = KVM_MAX_VCPU_IDS;
12224
12225 if (id >= kvm->arch.max_vcpu_ids)
12226 return -EINVAL;
12227
12228 return kvm_x86_call(vcpu_precreate)(kvm);
12229 }
12230
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)12231 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
12232 {
12233 struct page *page;
12234 int r;
12235
12236 vcpu->arch.last_vmentry_cpu = -1;
12237 vcpu->arch.regs_avail = ~0;
12238 vcpu->arch.regs_dirty = ~0;
12239
12240 kvm_gpc_init(&vcpu->arch.pv_time, vcpu->kvm);
12241
12242 if (!irqchip_in_kernel(vcpu->kvm) || kvm_vcpu_is_reset_bsp(vcpu))
12243 kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
12244 else
12245 kvm_set_mp_state(vcpu, KVM_MP_STATE_UNINITIALIZED);
12246
12247 r = kvm_mmu_create(vcpu);
12248 if (r < 0)
12249 return r;
12250
12251 r = kvm_create_lapic(vcpu);
12252 if (r < 0)
12253 goto fail_mmu_destroy;
12254
12255 r = -ENOMEM;
12256
12257 page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
12258 if (!page)
12259 goto fail_free_lapic;
12260 vcpu->arch.pio_data = page_address(page);
12261
12262 vcpu->arch.mce_banks = kcalloc(KVM_MAX_MCE_BANKS * 4, sizeof(u64),
12263 GFP_KERNEL_ACCOUNT);
12264 vcpu->arch.mci_ctl2_banks = kcalloc(KVM_MAX_MCE_BANKS, sizeof(u64),
12265 GFP_KERNEL_ACCOUNT);
12266 if (!vcpu->arch.mce_banks || !vcpu->arch.mci_ctl2_banks)
12267 goto fail_free_mce_banks;
12268 vcpu->arch.mcg_cap = KVM_MAX_MCE_BANKS;
12269
12270 if (!zalloc_cpumask_var(&vcpu->arch.wbinvd_dirty_mask,
12271 GFP_KERNEL_ACCOUNT))
12272 goto fail_free_mce_banks;
12273
12274 if (!alloc_emulate_ctxt(vcpu))
12275 goto free_wbinvd_dirty_mask;
12276
12277 if (!fpu_alloc_guest_fpstate(&vcpu->arch.guest_fpu)) {
12278 pr_err("failed to allocate vcpu's fpu\n");
12279 goto free_emulate_ctxt;
12280 }
12281
12282 kvm_async_pf_hash_reset(vcpu);
12283
12284 if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_STUFF_FEATURE_MSRS)) {
12285 vcpu->arch.arch_capabilities = kvm_get_arch_capabilities();
12286 vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT;
12287 vcpu->arch.perf_capabilities = kvm_caps.supported_perf_cap;
12288 }
12289 kvm_pmu_init(vcpu);
12290
12291 vcpu->arch.pending_external_vector = -1;
12292 vcpu->arch.preempted_in_kernel = false;
12293
12294 #if IS_ENABLED(CONFIG_HYPERV)
12295 vcpu->arch.hv_root_tdp = INVALID_PAGE;
12296 #endif
12297
12298 r = kvm_x86_call(vcpu_create)(vcpu);
12299 if (r)
12300 goto free_guest_fpu;
12301
12302 kvm_xen_init_vcpu(vcpu);
12303 vcpu_load(vcpu);
12304 kvm_vcpu_after_set_cpuid(vcpu);
12305 kvm_set_tsc_khz(vcpu, vcpu->kvm->arch.default_tsc_khz);
12306 kvm_vcpu_reset(vcpu, false);
12307 kvm_init_mmu(vcpu);
12308 vcpu_put(vcpu);
12309 return 0;
12310
12311 free_guest_fpu:
12312 fpu_free_guest_fpstate(&vcpu->arch.guest_fpu);
12313 free_emulate_ctxt:
12314 kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt);
12315 free_wbinvd_dirty_mask:
12316 free_cpumask_var(vcpu->arch.wbinvd_dirty_mask);
12317 fail_free_mce_banks:
12318 kfree(vcpu->arch.mce_banks);
12319 kfree(vcpu->arch.mci_ctl2_banks);
12320 free_page((unsigned long)vcpu->arch.pio_data);
12321 fail_free_lapic:
12322 kvm_free_lapic(vcpu);
12323 fail_mmu_destroy:
12324 kvm_mmu_destroy(vcpu);
12325 return r;
12326 }
12327
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)12328 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
12329 {
12330 struct kvm *kvm = vcpu->kvm;
12331
12332 if (mutex_lock_killable(&vcpu->mutex))
12333 return;
12334 vcpu_load(vcpu);
12335 kvm_synchronize_tsc(vcpu, NULL);
12336 vcpu_put(vcpu);
12337
12338 /* poll control enabled by default */
12339 vcpu->arch.msr_kvm_poll_control = 1;
12340
12341 mutex_unlock(&vcpu->mutex);
12342
12343 if (kvmclock_periodic_sync && vcpu->vcpu_idx == 0)
12344 schedule_delayed_work(&kvm->arch.kvmclock_sync_work,
12345 KVMCLOCK_SYNC_PERIOD);
12346 }
12347
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)12348 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
12349 {
12350 int idx, cpu;
12351
12352 kvm_clear_async_pf_completion_queue(vcpu);
12353 kvm_mmu_unload(vcpu);
12354
12355 kvmclock_reset(vcpu);
12356
12357 for_each_possible_cpu(cpu)
12358 cmpxchg(per_cpu_ptr(&last_vcpu, cpu), vcpu, NULL);
12359
12360 kvm_x86_call(vcpu_free)(vcpu);
12361
12362 kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt);
12363 free_cpumask_var(vcpu->arch.wbinvd_dirty_mask);
12364 fpu_free_guest_fpstate(&vcpu->arch.guest_fpu);
12365
12366 kvm_xen_destroy_vcpu(vcpu);
12367 kvm_hv_vcpu_uninit(vcpu);
12368 kvm_pmu_destroy(vcpu);
12369 kfree(vcpu->arch.mce_banks);
12370 kfree(vcpu->arch.mci_ctl2_banks);
12371 kvm_free_lapic(vcpu);
12372 idx = srcu_read_lock(&vcpu->kvm->srcu);
12373 kvm_mmu_destroy(vcpu);
12374 srcu_read_unlock(&vcpu->kvm->srcu, idx);
12375 free_page((unsigned long)vcpu->arch.pio_data);
12376 kvfree(vcpu->arch.cpuid_entries);
12377 }
12378
kvm_vcpu_reset(struct kvm_vcpu * vcpu,bool init_event)12379 void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
12380 {
12381 struct kvm_cpuid_entry2 *cpuid_0x1;
12382 unsigned long old_cr0 = kvm_read_cr0(vcpu);
12383 unsigned long new_cr0;
12384
12385 /*
12386 * Several of the "set" flows, e.g. ->set_cr0(), read other registers
12387 * to handle side effects. RESET emulation hits those flows and relies
12388 * on emulated/virtualized registers, including those that are loaded
12389 * into hardware, to be zeroed at vCPU creation. Use CRs as a sentinel
12390 * to detect improper or missing initialization.
12391 */
12392 WARN_ON_ONCE(!init_event &&
12393 (old_cr0 || kvm_read_cr3(vcpu) || kvm_read_cr4(vcpu)));
12394
12395 /*
12396 * SVM doesn't unconditionally VM-Exit on INIT and SHUTDOWN, thus it's
12397 * possible to INIT the vCPU while L2 is active. Force the vCPU back
12398 * into L1 as EFER.SVME is cleared on INIT (along with all other EFER
12399 * bits), i.e. virtualization is disabled.
12400 */
12401 if (is_guest_mode(vcpu))
12402 kvm_leave_nested(vcpu);
12403
12404 kvm_lapic_reset(vcpu, init_event);
12405
12406 WARN_ON_ONCE(is_guest_mode(vcpu) || is_smm(vcpu));
12407 vcpu->arch.hflags = 0;
12408
12409 vcpu->arch.smi_pending = 0;
12410 vcpu->arch.smi_count = 0;
12411 atomic_set(&vcpu->arch.nmi_queued, 0);
12412 vcpu->arch.nmi_pending = 0;
12413 vcpu->arch.nmi_injected = false;
12414 kvm_clear_interrupt_queue(vcpu);
12415 kvm_clear_exception_queue(vcpu);
12416
12417 memset(vcpu->arch.db, 0, sizeof(vcpu->arch.db));
12418 kvm_update_dr0123(vcpu);
12419 vcpu->arch.dr6 = DR6_ACTIVE_LOW;
12420 vcpu->arch.dr7 = DR7_FIXED_1;
12421 kvm_update_dr7(vcpu);
12422
12423 vcpu->arch.cr2 = 0;
12424
12425 kvm_make_request(KVM_REQ_EVENT, vcpu);
12426 vcpu->arch.apf.msr_en_val = 0;
12427 vcpu->arch.apf.msr_int_val = 0;
12428 vcpu->arch.st.msr_val = 0;
12429
12430 kvmclock_reset(vcpu);
12431
12432 kvm_clear_async_pf_completion_queue(vcpu);
12433 kvm_async_pf_hash_reset(vcpu);
12434 vcpu->arch.apf.halted = false;
12435
12436 if (vcpu->arch.guest_fpu.fpstate && kvm_mpx_supported()) {
12437 struct fpstate *fpstate = vcpu->arch.guest_fpu.fpstate;
12438
12439 /*
12440 * All paths that lead to INIT are required to load the guest's
12441 * FPU state (because most paths are buried in KVM_RUN).
12442 */
12443 if (init_event)
12444 kvm_put_guest_fpu(vcpu);
12445
12446 fpstate_clear_xstate_component(fpstate, XFEATURE_BNDREGS);
12447 fpstate_clear_xstate_component(fpstate, XFEATURE_BNDCSR);
12448
12449 if (init_event)
12450 kvm_load_guest_fpu(vcpu);
12451 }
12452
12453 if (!init_event) {
12454 vcpu->arch.smbase = 0x30000;
12455
12456 vcpu->arch.pat = MSR_IA32_CR_PAT_DEFAULT;
12457
12458 vcpu->arch.msr_misc_features_enables = 0;
12459 vcpu->arch.ia32_misc_enable_msr = MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL |
12460 MSR_IA32_MISC_ENABLE_BTS_UNAVAIL;
12461
12462 __kvm_set_xcr(vcpu, 0, XFEATURE_MASK_FP);
12463 __kvm_set_msr(vcpu, MSR_IA32_XSS, 0, true);
12464 }
12465
12466 /* All GPRs except RDX (handled below) are zeroed on RESET/INIT. */
12467 memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
12468 kvm_register_mark_dirty(vcpu, VCPU_REGS_RSP);
12469
12470 /*
12471 * Fall back to KVM's default Family/Model/Stepping of 0x600 (P6/Athlon)
12472 * if no CPUID match is found. Note, it's impossible to get a match at
12473 * RESET since KVM emulates RESET before exposing the vCPU to userspace,
12474 * i.e. it's impossible for kvm_find_cpuid_entry() to find a valid entry
12475 * on RESET. But, go through the motions in case that's ever remedied.
12476 */
12477 cpuid_0x1 = kvm_find_cpuid_entry(vcpu, 1);
12478 kvm_rdx_write(vcpu, cpuid_0x1 ? cpuid_0x1->eax : 0x600);
12479
12480 kvm_x86_call(vcpu_reset)(vcpu, init_event);
12481
12482 kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
12483 kvm_rip_write(vcpu, 0xfff0);
12484
12485 vcpu->arch.cr3 = 0;
12486 kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
12487
12488 /*
12489 * CR0.CD/NW are set on RESET, preserved on INIT. Note, some versions
12490 * of Intel's SDM list CD/NW as being set on INIT, but they contradict
12491 * (or qualify) that with a footnote stating that CD/NW are preserved.
12492 */
12493 new_cr0 = X86_CR0_ET;
12494 if (init_event)
12495 new_cr0 |= (old_cr0 & (X86_CR0_NW | X86_CR0_CD));
12496 else
12497 new_cr0 |= X86_CR0_NW | X86_CR0_CD;
12498
12499 kvm_x86_call(set_cr0)(vcpu, new_cr0);
12500 kvm_x86_call(set_cr4)(vcpu, 0);
12501 kvm_x86_call(set_efer)(vcpu, 0);
12502 kvm_x86_call(update_exception_bitmap)(vcpu);
12503
12504 /*
12505 * On the standard CR0/CR4/EFER modification paths, there are several
12506 * complex conditions determining whether the MMU has to be reset and/or
12507 * which PCIDs have to be flushed. However, CR0.WP and the paging-related
12508 * bits in CR4 and EFER are irrelevant if CR0.PG was '0'; and a reset+flush
12509 * is needed anyway if CR0.PG was '1' (which can only happen for INIT, as
12510 * CR0 will be '0' prior to RESET). So we only need to check CR0.PG here.
12511 */
12512 if (old_cr0 & X86_CR0_PG) {
12513 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
12514 kvm_mmu_reset_context(vcpu);
12515 }
12516
12517 /*
12518 * Intel's SDM states that all TLB entries are flushed on INIT. AMD's
12519 * APM states the TLBs are untouched by INIT, but it also states that
12520 * the TLBs are flushed on "External initialization of the processor."
12521 * Flush the guest TLB regardless of vendor, there is no meaningful
12522 * benefit in relying on the guest to flush the TLB immediately after
12523 * INIT. A spurious TLB flush is benign and likely negligible from a
12524 * performance perspective.
12525 */
12526 if (init_event)
12527 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
12528 }
12529 EXPORT_SYMBOL_GPL(kvm_vcpu_reset);
12530
kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu * vcpu,u8 vector)12531 void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector)
12532 {
12533 struct kvm_segment cs;
12534
12535 kvm_get_segment(vcpu, &cs, VCPU_SREG_CS);
12536 cs.selector = vector << 8;
12537 cs.base = vector << 12;
12538 kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
12539 kvm_rip_write(vcpu, 0);
12540 }
12541 EXPORT_SYMBOL_GPL(kvm_vcpu_deliver_sipi_vector);
12542
kvm_arch_enable_virtualization(void)12543 void kvm_arch_enable_virtualization(void)
12544 {
12545 cpu_emergency_register_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
12546 }
12547
kvm_arch_disable_virtualization(void)12548 void kvm_arch_disable_virtualization(void)
12549 {
12550 cpu_emergency_unregister_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
12551 }
12552
kvm_arch_enable_virtualization_cpu(void)12553 int kvm_arch_enable_virtualization_cpu(void)
12554 {
12555 struct kvm *kvm;
12556 struct kvm_vcpu *vcpu;
12557 unsigned long i;
12558 int ret;
12559 u64 local_tsc;
12560 u64 max_tsc = 0;
12561 bool stable, backwards_tsc = false;
12562
12563 kvm_user_return_msr_cpu_online();
12564
12565 ret = kvm_x86_check_processor_compatibility();
12566 if (ret)
12567 return ret;
12568
12569 ret = kvm_x86_call(enable_virtualization_cpu)();
12570 if (ret != 0)
12571 return ret;
12572
12573 local_tsc = rdtsc();
12574 stable = !kvm_check_tsc_unstable();
12575 list_for_each_entry(kvm, &vm_list, vm_list) {
12576 kvm_for_each_vcpu(i, vcpu, kvm) {
12577 if (!stable && vcpu->cpu == smp_processor_id())
12578 kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
12579 if (stable && vcpu->arch.last_host_tsc > local_tsc) {
12580 backwards_tsc = true;
12581 if (vcpu->arch.last_host_tsc > max_tsc)
12582 max_tsc = vcpu->arch.last_host_tsc;
12583 }
12584 }
12585 }
12586
12587 /*
12588 * Sometimes, even reliable TSCs go backwards. This happens on
12589 * platforms that reset TSC during suspend or hibernate actions, but
12590 * maintain synchronization. We must compensate. Fortunately, we can
12591 * detect that condition here, which happens early in CPU bringup,
12592 * before any KVM threads can be running. Unfortunately, we can't
12593 * bring the TSCs fully up to date with real time, as we aren't yet far
12594 * enough into CPU bringup that we know how much real time has actually
12595 * elapsed; our helper function, ktime_get_boottime_ns() will be using boot
12596 * variables that haven't been updated yet.
12597 *
12598 * So we simply find the maximum observed TSC above, then record the
12599 * adjustment to TSC in each VCPU. When the VCPU later gets loaded,
12600 * the adjustment will be applied. Note that we accumulate
12601 * adjustments, in case multiple suspend cycles happen before some VCPU
12602 * gets a chance to run again. In the event that no KVM threads get a
12603 * chance to run, we will miss the entire elapsed period, as we'll have
12604 * reset last_host_tsc, so VCPUs will not have the TSC adjusted and may
12605 * loose cycle time. This isn't too big a deal, since the loss will be
12606 * uniform across all VCPUs (not to mention the scenario is extremely
12607 * unlikely). It is possible that a second hibernate recovery happens
12608 * much faster than a first, causing the observed TSC here to be
12609 * smaller; this would require additional padding adjustment, which is
12610 * why we set last_host_tsc to the local tsc observed here.
12611 *
12612 * N.B. - this code below runs only on platforms with reliable TSC,
12613 * as that is the only way backwards_tsc is set above. Also note
12614 * that this runs for ALL vcpus, which is not a bug; all VCPUs should
12615 * have the same delta_cyc adjustment applied if backwards_tsc
12616 * is detected. Note further, this adjustment is only done once,
12617 * as we reset last_host_tsc on all VCPUs to stop this from being
12618 * called multiple times (one for each physical CPU bringup).
12619 *
12620 * Platforms with unreliable TSCs don't have to deal with this, they
12621 * will be compensated by the logic in vcpu_load, which sets the TSC to
12622 * catchup mode. This will catchup all VCPUs to real time, but cannot
12623 * guarantee that they stay in perfect synchronization.
12624 */
12625 if (backwards_tsc) {
12626 u64 delta_cyc = max_tsc - local_tsc;
12627 list_for_each_entry(kvm, &vm_list, vm_list) {
12628 kvm->arch.backwards_tsc_observed = true;
12629 kvm_for_each_vcpu(i, vcpu, kvm) {
12630 vcpu->arch.tsc_offset_adjustment += delta_cyc;
12631 vcpu->arch.last_host_tsc = local_tsc;
12632 kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
12633 }
12634
12635 /*
12636 * We have to disable TSC offset matching.. if you were
12637 * booting a VM while issuing an S4 host suspend....
12638 * you may have some problem. Solving this issue is
12639 * left as an exercise to the reader.
12640 */
12641 kvm->arch.last_tsc_nsec = 0;
12642 kvm->arch.last_tsc_write = 0;
12643 }
12644
12645 }
12646 return 0;
12647 }
12648
kvm_arch_disable_virtualization_cpu(void)12649 void kvm_arch_disable_virtualization_cpu(void)
12650 {
12651 kvm_x86_call(disable_virtualization_cpu)();
12652 drop_user_return_notifiers();
12653 }
12654
kvm_vcpu_is_reset_bsp(struct kvm_vcpu * vcpu)12655 bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
12656 {
12657 return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id;
12658 }
12659 EXPORT_SYMBOL_GPL(kvm_vcpu_is_reset_bsp);
12660
kvm_vcpu_is_bsp(struct kvm_vcpu * vcpu)12661 bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
12662 {
12663 return (vcpu->arch.apic_base & MSR_IA32_APICBASE_BSP) != 0;
12664 }
12665
kvm_arch_free_vm(struct kvm * kvm)12666 void kvm_arch_free_vm(struct kvm *kvm)
12667 {
12668 #if IS_ENABLED(CONFIG_HYPERV)
12669 kfree(kvm->arch.hv_pa_pg);
12670 #endif
12671 __kvm_arch_free_vm(kvm);
12672 }
12673
12674
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)12675 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
12676 {
12677 int ret;
12678 unsigned long flags;
12679
12680 if (!kvm_is_vm_type_supported(type))
12681 return -EINVAL;
12682
12683 kvm->arch.vm_type = type;
12684 kvm->arch.has_private_mem =
12685 (type == KVM_X86_SW_PROTECTED_VM);
12686 /* Decided by the vendor code for other VM types. */
12687 kvm->arch.pre_fault_allowed =
12688 type == KVM_X86_DEFAULT_VM || type == KVM_X86_SW_PROTECTED_VM;
12689 kvm->arch.disabled_quirks = kvm_caps.inapplicable_quirks & kvm_caps.supported_quirks;
12690
12691 ret = kvm_page_track_init(kvm);
12692 if (ret)
12693 goto out;
12694
12695 ret = kvm_mmu_init_vm(kvm);
12696 if (ret)
12697 goto out_cleanup_page_track;
12698
12699 ret = kvm_x86_call(vm_init)(kvm);
12700 if (ret)
12701 goto out_uninit_mmu;
12702
12703 atomic_set(&kvm->arch.noncoherent_dma_count, 0);
12704
12705 raw_spin_lock_init(&kvm->arch.tsc_write_lock);
12706 mutex_init(&kvm->arch.apic_map_lock);
12707 seqcount_raw_spinlock_init(&kvm->arch.pvclock_sc, &kvm->arch.tsc_write_lock);
12708 kvm->arch.kvmclock_offset = -get_kvmclock_base_ns();
12709
12710 raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
12711 pvclock_update_vm_gtod_copy(kvm);
12712 raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
12713
12714 kvm->arch.default_tsc_khz = max_tsc_khz ? : tsc_khz;
12715 kvm->arch.apic_bus_cycle_ns = APIC_BUS_CYCLE_NS_DEFAULT;
12716 kvm->arch.guest_can_read_msr_platform_info = true;
12717 kvm->arch.enable_pmu = enable_pmu;
12718
12719 #if IS_ENABLED(CONFIG_HYPERV)
12720 spin_lock_init(&kvm->arch.hv_root_tdp_lock);
12721 kvm->arch.hv_root_tdp = INVALID_PAGE;
12722 #endif
12723
12724 INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn);
12725 INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn);
12726
12727 kvm_apicv_init(kvm);
12728 kvm_hv_init_vm(kvm);
12729 kvm_xen_init_vm(kvm);
12730
12731 if (ignore_msrs && !report_ignored_msrs) {
12732 pr_warn_once("Running KVM with ignore_msrs=1 and report_ignored_msrs=0 is not a\n"
12733 "a supported configuration. Lying to the guest about the existence of MSRs\n"
12734 "may cause the guest operating system to hang or produce errors. If a guest\n"
12735 "does not run without ignore_msrs=1, please report it to kvm@vger.kernel.org.\n");
12736 }
12737
12738 once_init(&kvm->arch.nx_once);
12739 return 0;
12740
12741 out_uninit_mmu:
12742 kvm_mmu_uninit_vm(kvm);
12743 out_cleanup_page_track:
12744 kvm_page_track_cleanup(kvm);
12745 out:
12746 return ret;
12747 }
12748
12749 /**
12750 * __x86_set_memory_region: Setup KVM internal memory slot
12751 *
12752 * @kvm: the kvm pointer to the VM.
12753 * @id: the slot ID to setup.
12754 * @gpa: the GPA to install the slot (unused when @size == 0).
12755 * @size: the size of the slot. Set to zero to uninstall a slot.
12756 *
12757 * This function helps to setup a KVM internal memory slot. Specify
12758 * @size > 0 to install a new slot, while @size == 0 to uninstall a
12759 * slot. The return code can be one of the following:
12760 *
12761 * HVA: on success (uninstall will return a bogus HVA)
12762 * -errno: on error
12763 *
12764 * The caller should always use IS_ERR() to check the return value
12765 * before use. Note, the KVM internal memory slots are guaranteed to
12766 * remain valid and unchanged until the VM is destroyed, i.e., the
12767 * GPA->HVA translation will not change. However, the HVA is a user
12768 * address, i.e. its accessibility is not guaranteed, and must be
12769 * accessed via __copy_{to,from}_user().
12770 */
__x86_set_memory_region(struct kvm * kvm,int id,gpa_t gpa,u32 size)12771 void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
12772 u32 size)
12773 {
12774 int i, r;
12775 unsigned long hva, old_npages;
12776 struct kvm_memslots *slots = kvm_memslots(kvm);
12777 struct kvm_memory_slot *slot;
12778
12779 lockdep_assert_held(&kvm->slots_lock);
12780
12781 if (WARN_ON(id >= KVM_MEM_SLOTS_NUM))
12782 return ERR_PTR_USR(-EINVAL);
12783
12784 slot = id_to_memslot(slots, id);
12785 if (size) {
12786 if (slot && slot->npages)
12787 return ERR_PTR_USR(-EEXIST);
12788
12789 /*
12790 * MAP_SHARED to prevent internal slot pages from being moved
12791 * by fork()/COW.
12792 */
12793 hva = vm_mmap(NULL, 0, size, PROT_READ | PROT_WRITE,
12794 MAP_SHARED | MAP_ANONYMOUS, 0);
12795 if (IS_ERR_VALUE(hva))
12796 return (void __user *)hva;
12797 } else {
12798 if (!slot || !slot->npages)
12799 return NULL;
12800
12801 old_npages = slot->npages;
12802 hva = slot->userspace_addr;
12803 }
12804
12805 for (i = 0; i < kvm_arch_nr_memslot_as_ids(kvm); i++) {
12806 struct kvm_userspace_memory_region2 m;
12807
12808 m.slot = id | (i << 16);
12809 m.flags = 0;
12810 m.guest_phys_addr = gpa;
12811 m.userspace_addr = hva;
12812 m.memory_size = size;
12813 r = kvm_set_internal_memslot(kvm, &m);
12814 if (r < 0)
12815 return ERR_PTR_USR(r);
12816 }
12817
12818 if (!size)
12819 vm_munmap(hva, old_npages * PAGE_SIZE);
12820
12821 return (void __user *)hva;
12822 }
12823 EXPORT_SYMBOL_GPL(__x86_set_memory_region);
12824
kvm_arch_pre_destroy_vm(struct kvm * kvm)12825 void kvm_arch_pre_destroy_vm(struct kvm *kvm)
12826 {
12827 /*
12828 * Stop all background workers and kthreads before destroying vCPUs, as
12829 * iterating over vCPUs in a different task while vCPUs are being freed
12830 * is unsafe, i.e. will lead to use-after-free. The PIT also needs to
12831 * be stopped before IRQ routing is freed.
12832 */
12833 cancel_delayed_work_sync(&kvm->arch.kvmclock_sync_work);
12834 cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work);
12835
12836 #ifdef CONFIG_KVM_IOAPIC
12837 kvm_free_pit(kvm);
12838 #endif
12839
12840 kvm_mmu_pre_destroy_vm(kvm);
12841 static_call_cond(kvm_x86_vm_pre_destroy)(kvm);
12842 }
12843
kvm_arch_destroy_vm(struct kvm * kvm)12844 void kvm_arch_destroy_vm(struct kvm *kvm)
12845 {
12846 if (current->mm == kvm->mm) {
12847 /*
12848 * Free memory regions allocated on behalf of userspace,
12849 * unless the memory map has changed due to process exit
12850 * or fd copying.
12851 */
12852 mutex_lock(&kvm->slots_lock);
12853 __x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
12854 0, 0);
12855 __x86_set_memory_region(kvm, IDENTITY_PAGETABLE_PRIVATE_MEMSLOT,
12856 0, 0);
12857 __x86_set_memory_region(kvm, TSS_PRIVATE_MEMSLOT, 0, 0);
12858 mutex_unlock(&kvm->slots_lock);
12859 }
12860 kvm_destroy_vcpus(kvm);
12861 kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1));
12862 #ifdef CONFIG_KVM_IOAPIC
12863 kvm_pic_destroy(kvm);
12864 kvm_ioapic_destroy(kvm);
12865 #endif
12866 kvfree(rcu_dereference_check(kvm->arch.apic_map, 1));
12867 kfree(srcu_dereference_check(kvm->arch.pmu_event_filter, &kvm->srcu, 1));
12868 kvm_mmu_uninit_vm(kvm);
12869 kvm_page_track_cleanup(kvm);
12870 kvm_xen_destroy_vm(kvm);
12871 kvm_hv_destroy_vm(kvm);
12872 kvm_x86_call(vm_destroy)(kvm);
12873 }
12874
memslot_rmap_free(struct kvm_memory_slot * slot)12875 static void memslot_rmap_free(struct kvm_memory_slot *slot)
12876 {
12877 int i;
12878
12879 for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
12880 vfree(slot->arch.rmap[i]);
12881 slot->arch.rmap[i] = NULL;
12882 }
12883 }
12884
kvm_arch_free_memslot(struct kvm * kvm,struct kvm_memory_slot * slot)12885 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
12886 {
12887 int i;
12888
12889 memslot_rmap_free(slot);
12890
12891 for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) {
12892 vfree(slot->arch.lpage_info[i - 1]);
12893 slot->arch.lpage_info[i - 1] = NULL;
12894 }
12895
12896 kvm_page_track_free_memslot(slot);
12897 }
12898
memslot_rmap_alloc(struct kvm_memory_slot * slot,unsigned long npages)12899 int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages)
12900 {
12901 const int sz = sizeof(*slot->arch.rmap[0]);
12902 int i;
12903
12904 for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
12905 int level = i + 1;
12906 int lpages = __kvm_mmu_slot_lpages(slot, npages, level);
12907
12908 if (slot->arch.rmap[i])
12909 continue;
12910
12911 slot->arch.rmap[i] = __vcalloc(lpages, sz, GFP_KERNEL_ACCOUNT);
12912 if (!slot->arch.rmap[i]) {
12913 memslot_rmap_free(slot);
12914 return -ENOMEM;
12915 }
12916 }
12917
12918 return 0;
12919 }
12920
kvm_alloc_memslot_metadata(struct kvm * kvm,struct kvm_memory_slot * slot)12921 static int kvm_alloc_memslot_metadata(struct kvm *kvm,
12922 struct kvm_memory_slot *slot)
12923 {
12924 unsigned long npages = slot->npages;
12925 int i, r;
12926
12927 /*
12928 * Clear out the previous array pointers for the KVM_MR_MOVE case. The
12929 * old arrays will be freed by kvm_set_memory_region() if installing
12930 * the new memslot is successful.
12931 */
12932 memset(&slot->arch, 0, sizeof(slot->arch));
12933
12934 if (kvm_memslots_have_rmaps(kvm)) {
12935 r = memslot_rmap_alloc(slot, npages);
12936 if (r)
12937 return r;
12938 }
12939
12940 for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) {
12941 struct kvm_lpage_info *linfo;
12942 unsigned long ugfn;
12943 int lpages;
12944 int level = i + 1;
12945
12946 lpages = __kvm_mmu_slot_lpages(slot, npages, level);
12947
12948 linfo = __vcalloc(lpages, sizeof(*linfo), GFP_KERNEL_ACCOUNT);
12949 if (!linfo)
12950 goto out_free;
12951
12952 slot->arch.lpage_info[i - 1] = linfo;
12953
12954 if (slot->base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
12955 linfo[0].disallow_lpage = 1;
12956 if ((slot->base_gfn + npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
12957 linfo[lpages - 1].disallow_lpage = 1;
12958 ugfn = slot->userspace_addr >> PAGE_SHIFT;
12959 /*
12960 * If the gfn and userspace address are not aligned wrt each
12961 * other, disable large page support for this slot.
12962 */
12963 if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1)) {
12964 unsigned long j;
12965
12966 for (j = 0; j < lpages; ++j)
12967 linfo[j].disallow_lpage = 1;
12968 }
12969 }
12970
12971 #ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES
12972 kvm_mmu_init_memslot_memory_attributes(kvm, slot);
12973 #endif
12974
12975 if (kvm_page_track_create_memslot(kvm, slot, npages))
12976 goto out_free;
12977
12978 return 0;
12979
12980 out_free:
12981 memslot_rmap_free(slot);
12982
12983 for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) {
12984 vfree(slot->arch.lpage_info[i - 1]);
12985 slot->arch.lpage_info[i - 1] = NULL;
12986 }
12987 return -ENOMEM;
12988 }
12989
kvm_arch_memslots_updated(struct kvm * kvm,u64 gen)12990 void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen)
12991 {
12992 struct kvm_vcpu *vcpu;
12993 unsigned long i;
12994
12995 /*
12996 * memslots->generation has been incremented.
12997 * mmio generation may have reached its maximum value.
12998 */
12999 kvm_mmu_invalidate_mmio_sptes(kvm, gen);
13000
13001 /* Force re-initialization of steal_time cache */
13002 kvm_for_each_vcpu(i, vcpu, kvm)
13003 kvm_vcpu_kick(vcpu);
13004 }
13005
kvm_arch_prepare_memory_region(struct kvm * kvm,const struct kvm_memory_slot * old,struct kvm_memory_slot * new,enum kvm_mr_change change)13006 int kvm_arch_prepare_memory_region(struct kvm *kvm,
13007 const struct kvm_memory_slot *old,
13008 struct kvm_memory_slot *new,
13009 enum kvm_mr_change change)
13010 {
13011 /*
13012 * KVM doesn't support moving memslots when there are external page
13013 * trackers attached to the VM, i.e. if KVMGT is in use.
13014 */
13015 if (change == KVM_MR_MOVE && kvm_page_track_has_external_user(kvm))
13016 return -EINVAL;
13017
13018 if (change == KVM_MR_CREATE || change == KVM_MR_MOVE) {
13019 if ((new->base_gfn + new->npages - 1) > kvm_mmu_max_gfn())
13020 return -EINVAL;
13021
13022 if (kvm_is_gfn_alias(kvm, new->base_gfn + new->npages - 1))
13023 return -EINVAL;
13024
13025 return kvm_alloc_memslot_metadata(kvm, new);
13026 }
13027
13028 if (change == KVM_MR_FLAGS_ONLY)
13029 memcpy(&new->arch, &old->arch, sizeof(old->arch));
13030 else if (WARN_ON_ONCE(change != KVM_MR_DELETE))
13031 return -EIO;
13032
13033 return 0;
13034 }
13035
13036
kvm_mmu_update_cpu_dirty_logging(struct kvm * kvm,bool enable)13037 static void kvm_mmu_update_cpu_dirty_logging(struct kvm *kvm, bool enable)
13038 {
13039 int nr_slots;
13040
13041 if (!kvm->arch.cpu_dirty_log_size)
13042 return;
13043
13044 nr_slots = atomic_read(&kvm->nr_memslots_dirty_logging);
13045 if ((enable && nr_slots == 1) || !nr_slots)
13046 kvm_make_all_cpus_request(kvm, KVM_REQ_UPDATE_CPU_DIRTY_LOGGING);
13047 }
13048
kvm_mmu_slot_apply_flags(struct kvm * kvm,struct kvm_memory_slot * old,const struct kvm_memory_slot * new,enum kvm_mr_change change)13049 static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
13050 struct kvm_memory_slot *old,
13051 const struct kvm_memory_slot *new,
13052 enum kvm_mr_change change)
13053 {
13054 u32 old_flags = old ? old->flags : 0;
13055 u32 new_flags = new ? new->flags : 0;
13056 bool log_dirty_pages = new_flags & KVM_MEM_LOG_DIRTY_PAGES;
13057
13058 /*
13059 * Update CPU dirty logging if dirty logging is being toggled. This
13060 * applies to all operations.
13061 */
13062 if ((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES)
13063 kvm_mmu_update_cpu_dirty_logging(kvm, log_dirty_pages);
13064
13065 /*
13066 * Nothing more to do for RO slots (which can't be dirtied and can't be
13067 * made writable) or CREATE/MOVE/DELETE of a slot.
13068 *
13069 * For a memslot with dirty logging disabled:
13070 * CREATE: No dirty mappings will already exist.
13071 * MOVE/DELETE: The old mappings will already have been cleaned up by
13072 * kvm_arch_flush_shadow_memslot()
13073 *
13074 * For a memslot with dirty logging enabled:
13075 * CREATE: No shadow pages exist, thus nothing to write-protect
13076 * and no dirty bits to clear.
13077 * MOVE/DELETE: The old mappings will already have been cleaned up by
13078 * kvm_arch_flush_shadow_memslot().
13079 */
13080 if ((change != KVM_MR_FLAGS_ONLY) || (new_flags & KVM_MEM_READONLY))
13081 return;
13082
13083 /*
13084 * READONLY and non-flags changes were filtered out above, and the only
13085 * other flag is LOG_DIRTY_PAGES, i.e. something is wrong if dirty
13086 * logging isn't being toggled on or off.
13087 */
13088 if (WARN_ON_ONCE(!((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES)))
13089 return;
13090
13091 if (!log_dirty_pages) {
13092 /*
13093 * Recover huge page mappings in the slot now that dirty logging
13094 * is disabled, i.e. now that KVM does not have to track guest
13095 * writes at 4KiB granularity.
13096 *
13097 * Dirty logging might be disabled by userspace if an ongoing VM
13098 * live migration is cancelled and the VM must continue running
13099 * on the source.
13100 */
13101 kvm_mmu_recover_huge_pages(kvm, new);
13102 } else {
13103 /*
13104 * Initially-all-set does not require write protecting any page,
13105 * because they're all assumed to be dirty.
13106 */
13107 if (kvm_dirty_log_manual_protect_and_init_set(kvm))
13108 return;
13109
13110 if (READ_ONCE(eager_page_split))
13111 kvm_mmu_slot_try_split_huge_pages(kvm, new, PG_LEVEL_4K);
13112
13113 if (kvm->arch.cpu_dirty_log_size) {
13114 kvm_mmu_slot_leaf_clear_dirty(kvm, new);
13115 kvm_mmu_slot_remove_write_access(kvm, new, PG_LEVEL_2M);
13116 } else {
13117 kvm_mmu_slot_remove_write_access(kvm, new, PG_LEVEL_4K);
13118 }
13119
13120 /*
13121 * Unconditionally flush the TLBs after enabling dirty logging.
13122 * A flush is almost always going to be necessary (see below),
13123 * and unconditionally flushing allows the helpers to omit
13124 * the subtly complex checks when removing write access.
13125 *
13126 * Do the flush outside of mmu_lock to reduce the amount of
13127 * time mmu_lock is held. Flushing after dropping mmu_lock is
13128 * safe as KVM only needs to guarantee the slot is fully
13129 * write-protected before returning to userspace, i.e. before
13130 * userspace can consume the dirty status.
13131 *
13132 * Flushing outside of mmu_lock requires KVM to be careful when
13133 * making decisions based on writable status of an SPTE, e.g. a
13134 * !writable SPTE doesn't guarantee a CPU can't perform writes.
13135 *
13136 * Specifically, KVM also write-protects guest page tables to
13137 * monitor changes when using shadow paging, and must guarantee
13138 * no CPUs can write to those page before mmu_lock is dropped.
13139 * Because CPUs may have stale TLB entries at this point, a
13140 * !writable SPTE doesn't guarantee CPUs can't perform writes.
13141 *
13142 * KVM also allows making SPTES writable outside of mmu_lock,
13143 * e.g. to allow dirty logging without taking mmu_lock.
13144 *
13145 * To handle these scenarios, KVM uses a separate software-only
13146 * bit (MMU-writable) to track if a SPTE is !writable due to
13147 * a guest page table being write-protected (KVM clears the
13148 * MMU-writable flag when write-protecting for shadow paging).
13149 *
13150 * The use of MMU-writable is also the primary motivation for
13151 * the unconditional flush. Because KVM must guarantee that a
13152 * CPU doesn't contain stale, writable TLB entries for a
13153 * !MMU-writable SPTE, KVM must flush if it encounters any
13154 * MMU-writable SPTE regardless of whether the actual hardware
13155 * writable bit was set. I.e. KVM is almost guaranteed to need
13156 * to flush, while unconditionally flushing allows the "remove
13157 * write access" helpers to ignore MMU-writable entirely.
13158 *
13159 * See is_writable_pte() for more details (the case involving
13160 * access-tracked SPTEs is particularly relevant).
13161 */
13162 kvm_flush_remote_tlbs_memslot(kvm, new);
13163 }
13164 }
13165
kvm_arch_commit_memory_region(struct kvm * kvm,struct kvm_memory_slot * old,const struct kvm_memory_slot * new,enum kvm_mr_change change)13166 void kvm_arch_commit_memory_region(struct kvm *kvm,
13167 struct kvm_memory_slot *old,
13168 const struct kvm_memory_slot *new,
13169 enum kvm_mr_change change)
13170 {
13171 if (change == KVM_MR_DELETE)
13172 kvm_page_track_delete_slot(kvm, old);
13173
13174 if (!kvm->arch.n_requested_mmu_pages &&
13175 (change == KVM_MR_CREATE || change == KVM_MR_DELETE)) {
13176 unsigned long nr_mmu_pages;
13177
13178 nr_mmu_pages = kvm->nr_memslot_pages / KVM_MEMSLOT_PAGES_TO_MMU_PAGES_RATIO;
13179 nr_mmu_pages = max(nr_mmu_pages, KVM_MIN_ALLOC_MMU_PAGES);
13180 kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);
13181 }
13182
13183 kvm_mmu_slot_apply_flags(kvm, old, new, change);
13184
13185 /* Free the arrays associated with the old memslot. */
13186 if (change == KVM_MR_MOVE)
13187 kvm_arch_free_memslot(kvm, old);
13188 }
13189
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)13190 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
13191 {
13192 WARN_ON_ONCE(!kvm_arch_pmi_in_guest(vcpu));
13193
13194 if (vcpu->arch.guest_state_protected)
13195 return true;
13196
13197 return kvm_x86_call(get_cpl)(vcpu) == 0;
13198 }
13199
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)13200 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
13201 {
13202 WARN_ON_ONCE(!kvm_arch_pmi_in_guest(vcpu));
13203
13204 if (vcpu->arch.guest_state_protected)
13205 return 0;
13206
13207 return kvm_rip_read(vcpu);
13208 }
13209
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)13210 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
13211 {
13212 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
13213 }
13214
kvm_arch_interrupt_allowed(struct kvm_vcpu * vcpu)13215 int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu)
13216 {
13217 return kvm_x86_call(interrupt_allowed)(vcpu, false);
13218 }
13219
kvm_get_linear_rip(struct kvm_vcpu * vcpu)13220 unsigned long kvm_get_linear_rip(struct kvm_vcpu *vcpu)
13221 {
13222 /* Can't read the RIP when guest state is protected, just return 0 */
13223 if (vcpu->arch.guest_state_protected)
13224 return 0;
13225
13226 if (is_64_bit_mode(vcpu))
13227 return kvm_rip_read(vcpu);
13228 return (u32)(get_segment_base(vcpu, VCPU_SREG_CS) +
13229 kvm_rip_read(vcpu));
13230 }
13231 EXPORT_SYMBOL_GPL(kvm_get_linear_rip);
13232
kvm_is_linear_rip(struct kvm_vcpu * vcpu,unsigned long linear_rip)13233 bool kvm_is_linear_rip(struct kvm_vcpu *vcpu, unsigned long linear_rip)
13234 {
13235 return kvm_get_linear_rip(vcpu) == linear_rip;
13236 }
13237 EXPORT_SYMBOL_GPL(kvm_is_linear_rip);
13238
kvm_get_rflags(struct kvm_vcpu * vcpu)13239 unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu)
13240 {
13241 unsigned long rflags;
13242
13243 rflags = kvm_x86_call(get_rflags)(vcpu);
13244 if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
13245 rflags &= ~X86_EFLAGS_TF;
13246 return rflags;
13247 }
13248 EXPORT_SYMBOL_GPL(kvm_get_rflags);
13249
__kvm_set_rflags(struct kvm_vcpu * vcpu,unsigned long rflags)13250 static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
13251 {
13252 if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP &&
13253 kvm_is_linear_rip(vcpu, vcpu->arch.singlestep_rip))
13254 rflags |= X86_EFLAGS_TF;
13255 kvm_x86_call(set_rflags)(vcpu, rflags);
13256 }
13257
kvm_set_rflags(struct kvm_vcpu * vcpu,unsigned long rflags)13258 void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
13259 {
13260 __kvm_set_rflags(vcpu, rflags);
13261 kvm_make_request(KVM_REQ_EVENT, vcpu);
13262 }
13263 EXPORT_SYMBOL_GPL(kvm_set_rflags);
13264
kvm_async_pf_hash_fn(gfn_t gfn)13265 static inline u32 kvm_async_pf_hash_fn(gfn_t gfn)
13266 {
13267 BUILD_BUG_ON(!is_power_of_2(ASYNC_PF_PER_VCPU));
13268
13269 return hash_32(gfn & 0xffffffff, order_base_2(ASYNC_PF_PER_VCPU));
13270 }
13271
kvm_async_pf_next_probe(u32 key)13272 static inline u32 kvm_async_pf_next_probe(u32 key)
13273 {
13274 return (key + 1) & (ASYNC_PF_PER_VCPU - 1);
13275 }
13276
kvm_add_async_pf_gfn(struct kvm_vcpu * vcpu,gfn_t gfn)13277 static void kvm_add_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
13278 {
13279 u32 key = kvm_async_pf_hash_fn(gfn);
13280
13281 while (vcpu->arch.apf.gfns[key] != ~0)
13282 key = kvm_async_pf_next_probe(key);
13283
13284 vcpu->arch.apf.gfns[key] = gfn;
13285 }
13286
kvm_async_pf_gfn_slot(struct kvm_vcpu * vcpu,gfn_t gfn)13287 static u32 kvm_async_pf_gfn_slot(struct kvm_vcpu *vcpu, gfn_t gfn)
13288 {
13289 int i;
13290 u32 key = kvm_async_pf_hash_fn(gfn);
13291
13292 for (i = 0; i < ASYNC_PF_PER_VCPU &&
13293 (vcpu->arch.apf.gfns[key] != gfn &&
13294 vcpu->arch.apf.gfns[key] != ~0); i++)
13295 key = kvm_async_pf_next_probe(key);
13296
13297 return key;
13298 }
13299
kvm_find_async_pf_gfn(struct kvm_vcpu * vcpu,gfn_t gfn)13300 bool kvm_find_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
13301 {
13302 return vcpu->arch.apf.gfns[kvm_async_pf_gfn_slot(vcpu, gfn)] == gfn;
13303 }
13304
kvm_del_async_pf_gfn(struct kvm_vcpu * vcpu,gfn_t gfn)13305 static void kvm_del_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
13306 {
13307 u32 i, j, k;
13308
13309 i = j = kvm_async_pf_gfn_slot(vcpu, gfn);
13310
13311 if (WARN_ON_ONCE(vcpu->arch.apf.gfns[i] != gfn))
13312 return;
13313
13314 while (true) {
13315 vcpu->arch.apf.gfns[i] = ~0;
13316 do {
13317 j = kvm_async_pf_next_probe(j);
13318 if (vcpu->arch.apf.gfns[j] == ~0)
13319 return;
13320 k = kvm_async_pf_hash_fn(vcpu->arch.apf.gfns[j]);
13321 /*
13322 * k lies cyclically in ]i,j]
13323 * | i.k.j |
13324 * |....j i.k.| or |.k..j i...|
13325 */
13326 } while ((i <= j) ? (i < k && k <= j) : (i < k || k <= j));
13327 vcpu->arch.apf.gfns[i] = vcpu->arch.apf.gfns[j];
13328 i = j;
13329 }
13330 }
13331
apf_put_user_notpresent(struct kvm_vcpu * vcpu)13332 static inline int apf_put_user_notpresent(struct kvm_vcpu *vcpu)
13333 {
13334 u32 reason = KVM_PV_REASON_PAGE_NOT_PRESENT;
13335
13336 return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apf.data, &reason,
13337 sizeof(reason));
13338 }
13339
apf_put_user_ready(struct kvm_vcpu * vcpu,u32 token)13340 static inline int apf_put_user_ready(struct kvm_vcpu *vcpu, u32 token)
13341 {
13342 unsigned int offset = offsetof(struct kvm_vcpu_pv_apf_data, token);
13343
13344 return kvm_write_guest_offset_cached(vcpu->kvm, &vcpu->arch.apf.data,
13345 &token, offset, sizeof(token));
13346 }
13347
apf_pageready_slot_free(struct kvm_vcpu * vcpu)13348 static inline bool apf_pageready_slot_free(struct kvm_vcpu *vcpu)
13349 {
13350 unsigned int offset = offsetof(struct kvm_vcpu_pv_apf_data, token);
13351 u32 val;
13352
13353 if (kvm_read_guest_offset_cached(vcpu->kvm, &vcpu->arch.apf.data,
13354 &val, offset, sizeof(val)))
13355 return false;
13356
13357 return !val;
13358 }
13359
kvm_can_deliver_async_pf(struct kvm_vcpu * vcpu)13360 static bool kvm_can_deliver_async_pf(struct kvm_vcpu *vcpu)
13361 {
13362
13363 if (!kvm_pv_async_pf_enabled(vcpu))
13364 return false;
13365
13366 if (!vcpu->arch.apf.send_always &&
13367 (vcpu->arch.guest_state_protected || !kvm_x86_call(get_cpl)(vcpu)))
13368 return false;
13369
13370 if (is_guest_mode(vcpu)) {
13371 /*
13372 * L1 needs to opt into the special #PF vmexits that are
13373 * used to deliver async page faults.
13374 */
13375 return vcpu->arch.apf.delivery_as_pf_vmexit;
13376 } else {
13377 /*
13378 * Play it safe in case the guest temporarily disables paging.
13379 * The real mode IDT in particular is unlikely to have a #PF
13380 * exception setup.
13381 */
13382 return is_paging(vcpu);
13383 }
13384 }
13385
kvm_can_do_async_pf(struct kvm_vcpu * vcpu)13386 bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu)
13387 {
13388 if (unlikely(!lapic_in_kernel(vcpu) ||
13389 kvm_event_needs_reinjection(vcpu) ||
13390 kvm_is_exception_pending(vcpu)))
13391 return false;
13392
13393 if (kvm_hlt_in_guest(vcpu->kvm) && !kvm_can_deliver_async_pf(vcpu))
13394 return false;
13395
13396 /*
13397 * If interrupts are off we cannot even use an artificial
13398 * halt state.
13399 */
13400 return kvm_arch_interrupt_allowed(vcpu);
13401 }
13402
kvm_arch_async_page_not_present(struct kvm_vcpu * vcpu,struct kvm_async_pf * work)13403 bool kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu,
13404 struct kvm_async_pf *work)
13405 {
13406 struct x86_exception fault;
13407
13408 trace_kvm_async_pf_not_present(work->arch.token, work->cr2_or_gpa);
13409 kvm_add_async_pf_gfn(vcpu, work->arch.gfn);
13410
13411 if (kvm_can_deliver_async_pf(vcpu) &&
13412 !apf_put_user_notpresent(vcpu)) {
13413 fault.vector = PF_VECTOR;
13414 fault.error_code_valid = true;
13415 fault.error_code = 0;
13416 fault.nested_page_fault = false;
13417 fault.address = work->arch.token;
13418 fault.async_page_fault = true;
13419 kvm_inject_page_fault(vcpu, &fault);
13420 return true;
13421 } else {
13422 /*
13423 * It is not possible to deliver a paravirtualized asynchronous
13424 * page fault, but putting the guest in an artificial halt state
13425 * can be beneficial nevertheless: if an interrupt arrives, we
13426 * can deliver it timely and perhaps the guest will schedule
13427 * another process. When the instruction that triggered a page
13428 * fault is retried, hopefully the page will be ready in the host.
13429 */
13430 kvm_make_request(KVM_REQ_APF_HALT, vcpu);
13431 return false;
13432 }
13433 }
13434
kvm_arch_async_page_present(struct kvm_vcpu * vcpu,struct kvm_async_pf * work)13435 void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
13436 struct kvm_async_pf *work)
13437 {
13438 struct kvm_lapic_irq irq = {
13439 .delivery_mode = APIC_DM_FIXED,
13440 .vector = vcpu->arch.apf.vec
13441 };
13442
13443 if (work->wakeup_all)
13444 work->arch.token = ~0; /* broadcast wakeup */
13445 else
13446 kvm_del_async_pf_gfn(vcpu, work->arch.gfn);
13447 trace_kvm_async_pf_ready(work->arch.token, work->cr2_or_gpa);
13448
13449 if ((work->wakeup_all || work->notpresent_injected) &&
13450 kvm_pv_async_pf_enabled(vcpu) &&
13451 !apf_put_user_ready(vcpu, work->arch.token)) {
13452 vcpu->arch.apf.pageready_pending = true;
13453 kvm_apic_set_irq(vcpu, &irq, NULL);
13454 }
13455
13456 vcpu->arch.apf.halted = false;
13457 kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
13458 }
13459
kvm_arch_async_page_present_queued(struct kvm_vcpu * vcpu)13460 void kvm_arch_async_page_present_queued(struct kvm_vcpu *vcpu)
13461 {
13462 kvm_make_request(KVM_REQ_APF_READY, vcpu);
13463 if (!vcpu->arch.apf.pageready_pending)
13464 kvm_vcpu_kick(vcpu);
13465 }
13466
kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu * vcpu)13467 bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu)
13468 {
13469 if (!kvm_pv_async_pf_enabled(vcpu))
13470 return true;
13471 else
13472 return kvm_lapic_enabled(vcpu) && apf_pageready_slot_free(vcpu);
13473 }
13474
kvm_noncoherent_dma_assignment_start_or_stop(struct kvm * kvm)13475 static void kvm_noncoherent_dma_assignment_start_or_stop(struct kvm *kvm)
13476 {
13477 /*
13478 * Non-coherent DMA assignment and de-assignment may affect whether or
13479 * not KVM honors guest PAT, and thus may cause changes in EPT SPTEs
13480 * due to toggling the "ignore PAT" bit. Zap all SPTEs when the first
13481 * (or last) non-coherent device is (un)registered to so that new SPTEs
13482 * with the correct "ignore guest PAT" setting are created.
13483 *
13484 * If KVM always honors guest PAT, however, there is nothing to do.
13485 */
13486 if (kvm_check_has_quirk(kvm, KVM_X86_QUIRK_IGNORE_GUEST_PAT))
13487 kvm_zap_gfn_range(kvm, gpa_to_gfn(0), gpa_to_gfn(~0ULL));
13488 }
13489
kvm_arch_register_noncoherent_dma(struct kvm * kvm)13490 void kvm_arch_register_noncoherent_dma(struct kvm *kvm)
13491 {
13492 if (atomic_inc_return(&kvm->arch.noncoherent_dma_count) == 1)
13493 kvm_noncoherent_dma_assignment_start_or_stop(kvm);
13494 }
13495 EXPORT_SYMBOL_GPL(kvm_arch_register_noncoherent_dma);
13496
kvm_arch_unregister_noncoherent_dma(struct kvm * kvm)13497 void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm)
13498 {
13499 if (!atomic_dec_return(&kvm->arch.noncoherent_dma_count))
13500 kvm_noncoherent_dma_assignment_start_or_stop(kvm);
13501 }
13502 EXPORT_SYMBOL_GPL(kvm_arch_unregister_noncoherent_dma);
13503
kvm_arch_has_noncoherent_dma(struct kvm * kvm)13504 bool kvm_arch_has_noncoherent_dma(struct kvm *kvm)
13505 {
13506 return atomic_read(&kvm->arch.noncoherent_dma_count);
13507 }
13508 EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
13509
kvm_vector_hashing_enabled(void)13510 bool kvm_vector_hashing_enabled(void)
13511 {
13512 return vector_hashing;
13513 }
13514
kvm_arch_no_poll(struct kvm_vcpu * vcpu)13515 bool kvm_arch_no_poll(struct kvm_vcpu *vcpu)
13516 {
13517 return (vcpu->arch.msr_kvm_poll_control & 1) == 0;
13518 }
13519 EXPORT_SYMBOL_GPL(kvm_arch_no_poll);
13520
13521 #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE
kvm_arch_gmem_prepare(struct kvm * kvm,gfn_t gfn,kvm_pfn_t pfn,int max_order)13522 int kvm_arch_gmem_prepare(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, int max_order)
13523 {
13524 return kvm_x86_call(gmem_prepare)(kvm, pfn, gfn, max_order);
13525 }
13526 #endif
13527
13528 #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
kvm_arch_gmem_invalidate(kvm_pfn_t start,kvm_pfn_t end)13529 void kvm_arch_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end)
13530 {
13531 kvm_x86_call(gmem_invalidate)(start, end);
13532 }
13533 #endif
13534
kvm_spec_ctrl_test_value(u64 value)13535 int kvm_spec_ctrl_test_value(u64 value)
13536 {
13537 /*
13538 * test that setting IA32_SPEC_CTRL to given value
13539 * is allowed by the host processor
13540 */
13541
13542 u64 saved_value;
13543 unsigned long flags;
13544 int ret = 0;
13545
13546 local_irq_save(flags);
13547
13548 if (rdmsrq_safe(MSR_IA32_SPEC_CTRL, &saved_value))
13549 ret = 1;
13550 else if (wrmsrq_safe(MSR_IA32_SPEC_CTRL, value))
13551 ret = 1;
13552 else
13553 wrmsrq(MSR_IA32_SPEC_CTRL, saved_value);
13554
13555 local_irq_restore(flags);
13556
13557 return ret;
13558 }
13559 EXPORT_SYMBOL_GPL(kvm_spec_ctrl_test_value);
13560
kvm_fixup_and_inject_pf_error(struct kvm_vcpu * vcpu,gva_t gva,u16 error_code)13561 void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code)
13562 {
13563 struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
13564 struct x86_exception fault;
13565 u64 access = error_code &
13566 (PFERR_WRITE_MASK | PFERR_FETCH_MASK | PFERR_USER_MASK);
13567
13568 if (!(error_code & PFERR_PRESENT_MASK) ||
13569 mmu->gva_to_gpa(vcpu, mmu, gva, access, &fault) != INVALID_GPA) {
13570 /*
13571 * If vcpu->arch.walk_mmu->gva_to_gpa succeeded, the page
13572 * tables probably do not match the TLB. Just proceed
13573 * with the error code that the processor gave.
13574 */
13575 fault.vector = PF_VECTOR;
13576 fault.error_code_valid = true;
13577 fault.error_code = error_code;
13578 fault.nested_page_fault = false;
13579 fault.address = gva;
13580 fault.async_page_fault = false;
13581 }
13582 vcpu->arch.walk_mmu->inject_page_fault(vcpu, &fault);
13583 }
13584 EXPORT_SYMBOL_GPL(kvm_fixup_and_inject_pf_error);
13585
13586 /*
13587 * Handles kvm_read/write_guest_virt*() result and either injects #PF or returns
13588 * KVM_EXIT_INTERNAL_ERROR for cases not currently handled by KVM. Return value
13589 * indicates whether exit to userspace is needed.
13590 */
kvm_handle_memory_failure(struct kvm_vcpu * vcpu,int r,struct x86_exception * e)13591 int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r,
13592 struct x86_exception *e)
13593 {
13594 if (r == X86EMUL_PROPAGATE_FAULT) {
13595 if (KVM_BUG_ON(!e, vcpu->kvm))
13596 return -EIO;
13597
13598 kvm_inject_emulated_page_fault(vcpu, e);
13599 return 1;
13600 }
13601
13602 /*
13603 * In case kvm_read/write_guest_virt*() failed with X86EMUL_IO_NEEDED
13604 * while handling a VMX instruction KVM could've handled the request
13605 * correctly by exiting to userspace and performing I/O but there
13606 * doesn't seem to be a real use-case behind such requests, just return
13607 * KVM_EXIT_INTERNAL_ERROR for now.
13608 */
13609 kvm_prepare_emulation_failure_exit(vcpu);
13610
13611 return 0;
13612 }
13613 EXPORT_SYMBOL_GPL(kvm_handle_memory_failure);
13614
kvm_handle_invpcid(struct kvm_vcpu * vcpu,unsigned long type,gva_t gva)13615 int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva)
13616 {
13617 bool pcid_enabled;
13618 struct x86_exception e;
13619 struct {
13620 u64 pcid;
13621 u64 gla;
13622 } operand;
13623 int r;
13624
13625 r = kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e);
13626 if (r != X86EMUL_CONTINUE)
13627 return kvm_handle_memory_failure(vcpu, r, &e);
13628
13629 if (operand.pcid >> 12 != 0) {
13630 kvm_inject_gp(vcpu, 0);
13631 return 1;
13632 }
13633
13634 pcid_enabled = kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE);
13635
13636 switch (type) {
13637 case INVPCID_TYPE_INDIV_ADDR:
13638 /*
13639 * LAM doesn't apply to addresses that are inputs to TLB
13640 * invalidation.
13641 */
13642 if ((!pcid_enabled && (operand.pcid != 0)) ||
13643 is_noncanonical_invlpg_address(operand.gla, vcpu)) {
13644 kvm_inject_gp(vcpu, 0);
13645 return 1;
13646 }
13647 kvm_mmu_invpcid_gva(vcpu, operand.gla, operand.pcid);
13648 return kvm_skip_emulated_instruction(vcpu);
13649
13650 case INVPCID_TYPE_SINGLE_CTXT:
13651 if (!pcid_enabled && (operand.pcid != 0)) {
13652 kvm_inject_gp(vcpu, 0);
13653 return 1;
13654 }
13655
13656 kvm_invalidate_pcid(vcpu, operand.pcid);
13657 return kvm_skip_emulated_instruction(vcpu);
13658
13659 case INVPCID_TYPE_ALL_NON_GLOBAL:
13660 /*
13661 * Currently, KVM doesn't mark global entries in the shadow
13662 * page tables, so a non-global flush just degenerates to a
13663 * global flush. If needed, we could optimize this later by
13664 * keeping track of global entries in shadow page tables.
13665 */
13666
13667 fallthrough;
13668 case INVPCID_TYPE_ALL_INCL_GLOBAL:
13669 kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
13670 return kvm_skip_emulated_instruction(vcpu);
13671
13672 default:
13673 kvm_inject_gp(vcpu, 0);
13674 return 1;
13675 }
13676 }
13677 EXPORT_SYMBOL_GPL(kvm_handle_invpcid);
13678
complete_sev_es_emulated_mmio(struct kvm_vcpu * vcpu)13679 static int complete_sev_es_emulated_mmio(struct kvm_vcpu *vcpu)
13680 {
13681 struct kvm_run *run = vcpu->run;
13682 struct kvm_mmio_fragment *frag;
13683 unsigned int len;
13684
13685 BUG_ON(!vcpu->mmio_needed);
13686
13687 /* Complete previous fragment */
13688 frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment];
13689 len = min(8u, frag->len);
13690 if (!vcpu->mmio_is_write)
13691 memcpy(frag->data, run->mmio.data, len);
13692
13693 if (frag->len <= 8) {
13694 /* Switch to the next fragment. */
13695 frag++;
13696 vcpu->mmio_cur_fragment++;
13697 } else {
13698 /* Go forward to the next mmio piece. */
13699 frag->data += len;
13700 frag->gpa += len;
13701 frag->len -= len;
13702 }
13703
13704 if (vcpu->mmio_cur_fragment >= vcpu->mmio_nr_fragments) {
13705 vcpu->mmio_needed = 0;
13706
13707 // VMG change, at this point, we're always done
13708 // RIP has already been advanced
13709 return 1;
13710 }
13711
13712 // More MMIO is needed
13713 run->mmio.phys_addr = frag->gpa;
13714 run->mmio.len = min(8u, frag->len);
13715 run->mmio.is_write = vcpu->mmio_is_write;
13716 if (run->mmio.is_write)
13717 memcpy(run->mmio.data, frag->data, min(8u, frag->len));
13718 run->exit_reason = KVM_EXIT_MMIO;
13719
13720 vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio;
13721
13722 return 0;
13723 }
13724
kvm_sev_es_mmio_write(struct kvm_vcpu * vcpu,gpa_t gpa,unsigned int bytes,void * data)13725 int kvm_sev_es_mmio_write(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned int bytes,
13726 void *data)
13727 {
13728 int handled;
13729 struct kvm_mmio_fragment *frag;
13730
13731 if (!data)
13732 return -EINVAL;
13733
13734 handled = write_emultor.read_write_mmio(vcpu, gpa, bytes, data);
13735 if (handled == bytes)
13736 return 1;
13737
13738 bytes -= handled;
13739 gpa += handled;
13740 data += handled;
13741
13742 /*TODO: Check if need to increment number of frags */
13743 frag = vcpu->mmio_fragments;
13744 vcpu->mmio_nr_fragments = 1;
13745 frag->len = bytes;
13746 frag->gpa = gpa;
13747 frag->data = data;
13748
13749 vcpu->mmio_needed = 1;
13750 vcpu->mmio_cur_fragment = 0;
13751
13752 vcpu->run->mmio.phys_addr = gpa;
13753 vcpu->run->mmio.len = min(8u, frag->len);
13754 vcpu->run->mmio.is_write = 1;
13755 memcpy(vcpu->run->mmio.data, frag->data, min(8u, frag->len));
13756 vcpu->run->exit_reason = KVM_EXIT_MMIO;
13757
13758 vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio;
13759
13760 return 0;
13761 }
13762 EXPORT_SYMBOL_GPL(kvm_sev_es_mmio_write);
13763
kvm_sev_es_mmio_read(struct kvm_vcpu * vcpu,gpa_t gpa,unsigned int bytes,void * data)13764 int kvm_sev_es_mmio_read(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned int bytes,
13765 void *data)
13766 {
13767 int handled;
13768 struct kvm_mmio_fragment *frag;
13769
13770 if (!data)
13771 return -EINVAL;
13772
13773 handled = read_emultor.read_write_mmio(vcpu, gpa, bytes, data);
13774 if (handled == bytes)
13775 return 1;
13776
13777 bytes -= handled;
13778 gpa += handled;
13779 data += handled;
13780
13781 /*TODO: Check if need to increment number of frags */
13782 frag = vcpu->mmio_fragments;
13783 vcpu->mmio_nr_fragments = 1;
13784 frag->len = bytes;
13785 frag->gpa = gpa;
13786 frag->data = data;
13787
13788 vcpu->mmio_needed = 1;
13789 vcpu->mmio_cur_fragment = 0;
13790
13791 vcpu->run->mmio.phys_addr = gpa;
13792 vcpu->run->mmio.len = min(8u, frag->len);
13793 vcpu->run->mmio.is_write = 0;
13794 vcpu->run->exit_reason = KVM_EXIT_MMIO;
13795
13796 vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio;
13797
13798 return 0;
13799 }
13800 EXPORT_SYMBOL_GPL(kvm_sev_es_mmio_read);
13801
advance_sev_es_emulated_pio(struct kvm_vcpu * vcpu,unsigned count,int size)13802 static void advance_sev_es_emulated_pio(struct kvm_vcpu *vcpu, unsigned count, int size)
13803 {
13804 vcpu->arch.sev_pio_count -= count;
13805 vcpu->arch.sev_pio_data += count * size;
13806 }
13807
13808 static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size,
13809 unsigned int port);
13810
complete_sev_es_emulated_outs(struct kvm_vcpu * vcpu)13811 static int complete_sev_es_emulated_outs(struct kvm_vcpu *vcpu)
13812 {
13813 int size = vcpu->arch.pio.size;
13814 int port = vcpu->arch.pio.port;
13815
13816 vcpu->arch.pio.count = 0;
13817 if (vcpu->arch.sev_pio_count)
13818 return kvm_sev_es_outs(vcpu, size, port);
13819 return 1;
13820 }
13821
kvm_sev_es_outs(struct kvm_vcpu * vcpu,unsigned int size,unsigned int port)13822 static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size,
13823 unsigned int port)
13824 {
13825 for (;;) {
13826 unsigned int count =
13827 min_t(unsigned int, PAGE_SIZE / size, vcpu->arch.sev_pio_count);
13828 int ret = emulator_pio_out(vcpu, size, port, vcpu->arch.sev_pio_data, count);
13829
13830 /* memcpy done already by emulator_pio_out. */
13831 advance_sev_es_emulated_pio(vcpu, count, size);
13832 if (!ret)
13833 break;
13834
13835 /* Emulation done by the kernel. */
13836 if (!vcpu->arch.sev_pio_count)
13837 return 1;
13838 }
13839
13840 vcpu->arch.complete_userspace_io = complete_sev_es_emulated_outs;
13841 return 0;
13842 }
13843
13844 static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size,
13845 unsigned int port);
13846
complete_sev_es_emulated_ins(struct kvm_vcpu * vcpu)13847 static int complete_sev_es_emulated_ins(struct kvm_vcpu *vcpu)
13848 {
13849 unsigned count = vcpu->arch.pio.count;
13850 int size = vcpu->arch.pio.size;
13851 int port = vcpu->arch.pio.port;
13852
13853 complete_emulator_pio_in(vcpu, vcpu->arch.sev_pio_data);
13854 advance_sev_es_emulated_pio(vcpu, count, size);
13855 if (vcpu->arch.sev_pio_count)
13856 return kvm_sev_es_ins(vcpu, size, port);
13857 return 1;
13858 }
13859
kvm_sev_es_ins(struct kvm_vcpu * vcpu,unsigned int size,unsigned int port)13860 static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size,
13861 unsigned int port)
13862 {
13863 for (;;) {
13864 unsigned int count =
13865 min_t(unsigned int, PAGE_SIZE / size, vcpu->arch.sev_pio_count);
13866 if (!emulator_pio_in(vcpu, size, port, vcpu->arch.sev_pio_data, count))
13867 break;
13868
13869 /* Emulation done by the kernel. */
13870 advance_sev_es_emulated_pio(vcpu, count, size);
13871 if (!vcpu->arch.sev_pio_count)
13872 return 1;
13873 }
13874
13875 vcpu->arch.complete_userspace_io = complete_sev_es_emulated_ins;
13876 return 0;
13877 }
13878
kvm_sev_es_string_io(struct kvm_vcpu * vcpu,unsigned int size,unsigned int port,void * data,unsigned int count,int in)13879 int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
13880 unsigned int port, void *data, unsigned int count,
13881 int in)
13882 {
13883 vcpu->arch.sev_pio_data = data;
13884 vcpu->arch.sev_pio_count = count;
13885 return in ? kvm_sev_es_ins(vcpu, size, port)
13886 : kvm_sev_es_outs(vcpu, size, port);
13887 }
13888 EXPORT_SYMBOL_GPL(kvm_sev_es_string_io);
13889
13890 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
13891 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
13892 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_mmio);
13893 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
13894 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
13895 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
13896 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_msr);
13897 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cr);
13898 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter);
13899 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit);
13900 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit_inject);
13901 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intr_vmexit);
13902 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter_failed);
13903 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga);
13904 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_skinit);
13905 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts);
13906 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_write_tsc_offset);
13907 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_ple_window_update);
13908 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pml_full);
13909 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_unaccelerated_access);
13910 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_incomplete_ipi);
13911 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_ga_log);
13912 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_kick_vcpu_slowpath);
13913 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_doorbell);
13914 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_apicv_accept_irq);
13915 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_enter);
13916 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_exit);
13917 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_msr_protocol_enter);
13918 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_msr_protocol_exit);
13919 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_rmp_fault);
13920
kvm_x86_init(void)13921 static int __init kvm_x86_init(void)
13922 {
13923 kvm_init_xstate_sizes();
13924
13925 kvm_mmu_x86_module_init();
13926 mitigate_smt_rsb &= boot_cpu_has_bug(X86_BUG_SMT_RSB) && cpu_smt_possible();
13927 return 0;
13928 }
13929 module_init(kvm_x86_init);
13930
kvm_x86_exit(void)13931 static void __exit kvm_x86_exit(void)
13932 {
13933 WARN_ON_ONCE(static_branch_unlikely(&kvm_has_noapic_vcpu));
13934 }
13935 module_exit(kvm_x86_exit);
13936