1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Kernel-based Virtual Machine driver for Linux
4 *
5 * AMD SVM support
6 *
7 * Copyright (C) 2006 Qumranet, Inc.
8 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
9 *
10 * Authors:
11 * Yaniv Kamay <yaniv@qumranet.com>
12 * Avi Kivity <avi@qumranet.com>
13 */
14
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17 #include <linux/kvm_types.h>
18 #include <linux/kvm_host.h>
19 #include <linux/kernel.h>
20
21 #include <asm/msr-index.h>
22 #include <asm/debugreg.h>
23
24 #include "kvm_emulate.h"
25 #include "trace.h"
26 #include "mmu.h"
27 #include "x86.h"
28 #include "smm.h"
29 #include "cpuid.h"
30 #include "lapic.h"
31 #include "svm.h"
32 #include "hyperv.h"
33
34 #define CC KVM_NESTED_VMENTER_CONSISTENCY_CHECK
35
nested_svm_inject_npf_exit(struct kvm_vcpu * vcpu,struct x86_exception * fault)36 static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
37 struct x86_exception *fault)
38 {
39 struct vcpu_svm *svm = to_svm(vcpu);
40 struct vmcb *vmcb = svm->vmcb;
41
42 if (vmcb->control.exit_code != SVM_EXIT_NPF) {
43 /*
44 * TODO: track the cause of the nested page fault, and
45 * correctly fill in the high bits of exit_info_1.
46 */
47 vmcb->control.exit_code = SVM_EXIT_NPF;
48 vmcb->control.exit_code_hi = 0;
49 vmcb->control.exit_info_1 = (1ULL << 32);
50 vmcb->control.exit_info_2 = fault->address;
51 }
52
53 vmcb->control.exit_info_1 &= ~0xffffffffULL;
54 vmcb->control.exit_info_1 |= fault->error_code;
55
56 nested_svm_vmexit(svm);
57 }
58
nested_svm_get_tdp_pdptr(struct kvm_vcpu * vcpu,int index)59 static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index)
60 {
61 struct vcpu_svm *svm = to_svm(vcpu);
62 u64 cr3 = svm->nested.ctl.nested_cr3;
63 u64 pdpte;
64 int ret;
65
66 /*
67 * Note, nCR3 is "assumed" to be 32-byte aligned, i.e. the CPU ignores
68 * nCR3[4:0] when loading PDPTEs from memory.
69 */
70 ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(cr3), &pdpte,
71 (cr3 & GENMASK(11, 5)) + index * 8, 8);
72 if (ret)
73 return 0;
74 return pdpte;
75 }
76
nested_svm_get_tdp_cr3(struct kvm_vcpu * vcpu)77 static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu)
78 {
79 struct vcpu_svm *svm = to_svm(vcpu);
80
81 return svm->nested.ctl.nested_cr3;
82 }
83
nested_svm_init_mmu_context(struct kvm_vcpu * vcpu)84 static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
85 {
86 struct vcpu_svm *svm = to_svm(vcpu);
87
88 WARN_ON(mmu_is_nested(vcpu));
89
90 vcpu->arch.mmu = &vcpu->arch.guest_mmu;
91
92 /*
93 * The NPT format depends on L1's CR4 and EFER, which is in vmcb01. Note,
94 * when called via KVM_SET_NESTED_STATE, that state may _not_ match current
95 * vCPU state. CR0.WP is explicitly ignored, while CR0.PG is required.
96 */
97 kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, svm->vmcb01.ptr->save.cr4,
98 svm->vmcb01.ptr->save.efer,
99 svm->nested.ctl.nested_cr3);
100 vcpu->arch.mmu->get_guest_pgd = nested_svm_get_tdp_cr3;
101 vcpu->arch.mmu->get_pdptr = nested_svm_get_tdp_pdptr;
102 vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit;
103 vcpu->arch.walk_mmu = &vcpu->arch.nested_mmu;
104 }
105
nested_svm_uninit_mmu_context(struct kvm_vcpu * vcpu)106 static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)
107 {
108 vcpu->arch.mmu = &vcpu->arch.root_mmu;
109 vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;
110 }
111
nested_vmcb_needs_vls_intercept(struct vcpu_svm * svm)112 static bool nested_vmcb_needs_vls_intercept(struct vcpu_svm *svm)
113 {
114 if (!guest_cpu_cap_has(&svm->vcpu, X86_FEATURE_V_VMSAVE_VMLOAD))
115 return true;
116
117 if (!nested_npt_enabled(svm))
118 return true;
119
120 if (!(svm->nested.ctl.virt_ext & VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK))
121 return true;
122
123 return false;
124 }
125
recalc_intercepts(struct vcpu_svm * svm)126 void recalc_intercepts(struct vcpu_svm *svm)
127 {
128 struct vmcb_control_area *c, *h;
129 struct vmcb_ctrl_area_cached *g;
130 unsigned int i;
131
132 vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
133
134 if (!is_guest_mode(&svm->vcpu))
135 return;
136
137 c = &svm->vmcb->control;
138 h = &svm->vmcb01.ptr->control;
139 g = &svm->nested.ctl;
140
141 for (i = 0; i < MAX_INTERCEPT; i++)
142 c->intercepts[i] = h->intercepts[i];
143
144 if (g->int_ctl & V_INTR_MASKING_MASK) {
145 /*
146 * If L2 is active and V_INTR_MASKING is enabled in vmcb12,
147 * disable intercept of CR8 writes as L2's CR8 does not affect
148 * any interrupt KVM may want to inject.
149 *
150 * Similarly, disable intercept of virtual interrupts (used to
151 * detect interrupt windows) if the saved RFLAGS.IF is '0', as
152 * the effective RFLAGS.IF for L1 interrupts will never be set
153 * while L2 is running (L2's RFLAGS.IF doesn't affect L1 IRQs).
154 */
155 vmcb_clr_intercept(c, INTERCEPT_CR8_WRITE);
156 if (!(svm->vmcb01.ptr->save.rflags & X86_EFLAGS_IF))
157 vmcb_clr_intercept(c, INTERCEPT_VINTR);
158 }
159
160 /*
161 * We want to see VMMCALLs from a nested guest only when Hyper-V L2 TLB
162 * flush feature is enabled.
163 */
164 if (!nested_svm_l2_tlb_flush_enabled(&svm->vcpu))
165 vmcb_clr_intercept(c, INTERCEPT_VMMCALL);
166
167 for (i = 0; i < MAX_INTERCEPT; i++)
168 c->intercepts[i] |= g->intercepts[i];
169
170 /* If SMI is not intercepted, ignore guest SMI intercept as well */
171 if (!intercept_smi)
172 vmcb_clr_intercept(c, INTERCEPT_SMI);
173
174 if (nested_vmcb_needs_vls_intercept(svm)) {
175 /*
176 * If the virtual VMLOAD/VMSAVE is not enabled for the L2,
177 * we must intercept these instructions to correctly
178 * emulate them in case L1 doesn't intercept them.
179 */
180 vmcb_set_intercept(c, INTERCEPT_VMLOAD);
181 vmcb_set_intercept(c, INTERCEPT_VMSAVE);
182 } else {
183 WARN_ON(!(c->virt_ext & VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK));
184 }
185 }
186
187 /*
188 * This array (and its actual size) holds the set of offsets (indexing by chunk
189 * size) to process when merging vmcb12's MSRPM with vmcb01's MSRPM. Note, the
190 * set of MSRs for which interception is disabled in vmcb01 is per-vCPU, e.g.
191 * based on CPUID features. This array only tracks MSRs that *might* be passed
192 * through to the guest.
193 *
194 * Hardcode the capacity of the array based on the maximum number of _offsets_.
195 * MSRs are batched together, so there are fewer offsets than MSRs.
196 */
197 static int nested_svm_msrpm_merge_offsets[7] __ro_after_init;
198 static int nested_svm_nr_msrpm_merge_offsets __ro_after_init;
199 typedef unsigned long nsvm_msrpm_merge_t;
200
nested_svm_init_msrpm_merge_offsets(void)201 int __init nested_svm_init_msrpm_merge_offsets(void)
202 {
203 static const u32 merge_msrs[] __initconst = {
204 MSR_STAR,
205 MSR_IA32_SYSENTER_CS,
206 MSR_IA32_SYSENTER_EIP,
207 MSR_IA32_SYSENTER_ESP,
208 #ifdef CONFIG_X86_64
209 MSR_GS_BASE,
210 MSR_FS_BASE,
211 MSR_KERNEL_GS_BASE,
212 MSR_LSTAR,
213 MSR_CSTAR,
214 MSR_SYSCALL_MASK,
215 #endif
216 MSR_IA32_SPEC_CTRL,
217 MSR_IA32_PRED_CMD,
218 MSR_IA32_FLUSH_CMD,
219 MSR_IA32_APERF,
220 MSR_IA32_MPERF,
221 MSR_IA32_LASTBRANCHFROMIP,
222 MSR_IA32_LASTBRANCHTOIP,
223 MSR_IA32_LASTINTFROMIP,
224 MSR_IA32_LASTINTTOIP,
225 };
226 int i, j;
227
228 for (i = 0; i < ARRAY_SIZE(merge_msrs); i++) {
229 int bit_nr = svm_msrpm_bit_nr(merge_msrs[i]);
230 u32 offset;
231
232 if (WARN_ON(bit_nr < 0))
233 return -EIO;
234
235 /*
236 * Merging is done in chunks to reduce the number of accesses
237 * to L1's bitmap.
238 */
239 offset = bit_nr / BITS_PER_BYTE / sizeof(nsvm_msrpm_merge_t);
240
241 for (j = 0; j < nested_svm_nr_msrpm_merge_offsets; j++) {
242 if (nested_svm_msrpm_merge_offsets[j] == offset)
243 break;
244 }
245
246 if (j < nested_svm_nr_msrpm_merge_offsets)
247 continue;
248
249 if (WARN_ON(j >= ARRAY_SIZE(nested_svm_msrpm_merge_offsets)))
250 return -EIO;
251
252 nested_svm_msrpm_merge_offsets[j] = offset;
253 nested_svm_nr_msrpm_merge_offsets++;
254 }
255
256 return 0;
257 }
258
259 /*
260 * Merge L0's (KVM) and L1's (Nested VMCB) MSR permission bitmaps. The function
261 * is optimized in that it only merges the parts where KVM MSR permission bitmap
262 * may contain zero bits.
263 */
nested_svm_merge_msrpm(struct kvm_vcpu * vcpu)264 static bool nested_svm_merge_msrpm(struct kvm_vcpu *vcpu)
265 {
266 struct vcpu_svm *svm = to_svm(vcpu);
267 nsvm_msrpm_merge_t *msrpm02 = svm->nested.msrpm;
268 nsvm_msrpm_merge_t *msrpm01 = svm->msrpm;
269 int i;
270
271 /*
272 * MSR bitmap update can be skipped when:
273 * - MSR bitmap for L1 hasn't changed.
274 * - Nested hypervisor (L1) is attempting to launch the same L2 as
275 * before.
276 * - Nested hypervisor (L1) is using Hyper-V emulation interface and
277 * tells KVM (L0) there were no changes in MSR bitmap for L2.
278 */
279 #ifdef CONFIG_KVM_HYPERV
280 if (!svm->nested.force_msr_bitmap_recalc) {
281 struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
282
283 if (kvm_hv_hypercall_enabled(vcpu) &&
284 hve->hv_enlightenments_control.msr_bitmap &&
285 (svm->nested.ctl.clean & BIT(HV_VMCB_NESTED_ENLIGHTENMENTS)))
286 goto set_msrpm_base_pa;
287 }
288 #endif
289
290 if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
291 return true;
292
293 for (i = 0; i < nested_svm_nr_msrpm_merge_offsets; i++) {
294 const int p = nested_svm_msrpm_merge_offsets[i];
295 nsvm_msrpm_merge_t l1_val;
296 gpa_t gpa;
297
298 gpa = svm->nested.ctl.msrpm_base_pa + (p * sizeof(l1_val));
299
300 if (kvm_vcpu_read_guest(vcpu, gpa, &l1_val, sizeof(l1_val)))
301 return false;
302
303 msrpm02[p] = msrpm01[p] | l1_val;
304 }
305
306 svm->nested.force_msr_bitmap_recalc = false;
307
308 #ifdef CONFIG_KVM_HYPERV
309 set_msrpm_base_pa:
310 #endif
311 svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm));
312
313 return true;
314 }
315
316 /*
317 * Bits 11:0 of bitmap address are ignored by hardware
318 */
nested_svm_check_bitmap_pa(struct kvm_vcpu * vcpu,u64 pa,u32 size)319 static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size)
320 {
321 u64 addr = PAGE_ALIGN(pa);
322
323 return kvm_vcpu_is_legal_gpa(vcpu, addr) &&
324 kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1);
325 }
326
__nested_vmcb_check_controls(struct kvm_vcpu * vcpu,struct vmcb_ctrl_area_cached * control)327 static bool __nested_vmcb_check_controls(struct kvm_vcpu *vcpu,
328 struct vmcb_ctrl_area_cached *control)
329 {
330 if (CC(!vmcb12_is_intercept(control, INTERCEPT_VMRUN)))
331 return false;
332
333 if (CC(control->asid == 0))
334 return false;
335
336 if (CC((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && !npt_enabled))
337 return false;
338
339 if (CC(!nested_svm_check_bitmap_pa(vcpu, control->msrpm_base_pa,
340 MSRPM_SIZE)))
341 return false;
342 if (CC(!nested_svm_check_bitmap_pa(vcpu, control->iopm_base_pa,
343 IOPM_SIZE)))
344 return false;
345
346 if (CC((control->int_ctl & V_NMI_ENABLE_MASK) &&
347 !vmcb12_is_intercept(control, INTERCEPT_NMI))) {
348 return false;
349 }
350
351 return true;
352 }
353
354 /* Common checks that apply to both L1 and L2 state. */
__nested_vmcb_check_save(struct kvm_vcpu * vcpu,struct vmcb_save_area_cached * save)355 static bool __nested_vmcb_check_save(struct kvm_vcpu *vcpu,
356 struct vmcb_save_area_cached *save)
357 {
358 if (CC(!(save->efer & EFER_SVME)))
359 return false;
360
361 if (CC((save->cr0 & X86_CR0_CD) == 0 && (save->cr0 & X86_CR0_NW)) ||
362 CC(save->cr0 & ~0xffffffffULL))
363 return false;
364
365 if (CC(!kvm_dr6_valid(save->dr6)) || CC(!kvm_dr7_valid(save->dr7)))
366 return false;
367
368 /*
369 * These checks are also performed by KVM_SET_SREGS,
370 * except that EFER.LMA is not checked by SVM against
371 * CR0.PG && EFER.LME.
372 */
373 if ((save->efer & EFER_LME) && (save->cr0 & X86_CR0_PG)) {
374 if (CC(!(save->cr4 & X86_CR4_PAE)) ||
375 CC(!(save->cr0 & X86_CR0_PE)) ||
376 CC(!kvm_vcpu_is_legal_cr3(vcpu, save->cr3)))
377 return false;
378 }
379
380 /* Note, SVM doesn't have any additional restrictions on CR4. */
381 if (CC(!__kvm_is_valid_cr4(vcpu, save->cr4)))
382 return false;
383
384 if (CC(!kvm_valid_efer(vcpu, save->efer)))
385 return false;
386
387 return true;
388 }
389
nested_vmcb_check_save(struct kvm_vcpu * vcpu)390 static bool nested_vmcb_check_save(struct kvm_vcpu *vcpu)
391 {
392 struct vcpu_svm *svm = to_svm(vcpu);
393 struct vmcb_save_area_cached *save = &svm->nested.save;
394
395 return __nested_vmcb_check_save(vcpu, save);
396 }
397
nested_vmcb_check_controls(struct kvm_vcpu * vcpu)398 static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu)
399 {
400 struct vcpu_svm *svm = to_svm(vcpu);
401 struct vmcb_ctrl_area_cached *ctl = &svm->nested.ctl;
402
403 return __nested_vmcb_check_controls(vcpu, ctl);
404 }
405
406 static
__nested_copy_vmcb_control_to_cache(struct kvm_vcpu * vcpu,struct vmcb_ctrl_area_cached * to,struct vmcb_control_area * from)407 void __nested_copy_vmcb_control_to_cache(struct kvm_vcpu *vcpu,
408 struct vmcb_ctrl_area_cached *to,
409 struct vmcb_control_area *from)
410 {
411 unsigned int i;
412
413 for (i = 0; i < MAX_INTERCEPT; i++)
414 to->intercepts[i] = from->intercepts[i];
415
416 to->iopm_base_pa = from->iopm_base_pa;
417 to->msrpm_base_pa = from->msrpm_base_pa;
418 to->tsc_offset = from->tsc_offset;
419 to->tlb_ctl = from->tlb_ctl;
420 to->int_ctl = from->int_ctl;
421 to->int_vector = from->int_vector;
422 to->int_state = from->int_state;
423 to->exit_code = from->exit_code;
424 to->exit_code_hi = from->exit_code_hi;
425 to->exit_info_1 = from->exit_info_1;
426 to->exit_info_2 = from->exit_info_2;
427 to->exit_int_info = from->exit_int_info;
428 to->exit_int_info_err = from->exit_int_info_err;
429 to->nested_ctl = from->nested_ctl;
430 to->event_inj = from->event_inj;
431 to->event_inj_err = from->event_inj_err;
432 to->next_rip = from->next_rip;
433 to->nested_cr3 = from->nested_cr3;
434 to->virt_ext = from->virt_ext;
435 to->pause_filter_count = from->pause_filter_count;
436 to->pause_filter_thresh = from->pause_filter_thresh;
437
438 /* Copy asid here because nested_vmcb_check_controls will check it. */
439 to->asid = from->asid;
440 to->msrpm_base_pa &= ~0x0fffULL;
441 to->iopm_base_pa &= ~0x0fffULL;
442
443 #ifdef CONFIG_KVM_HYPERV
444 /* Hyper-V extensions (Enlightened VMCB) */
445 if (kvm_hv_hypercall_enabled(vcpu)) {
446 to->clean = from->clean;
447 memcpy(&to->hv_enlightenments, &from->hv_enlightenments,
448 sizeof(to->hv_enlightenments));
449 }
450 #endif
451 }
452
nested_copy_vmcb_control_to_cache(struct vcpu_svm * svm,struct vmcb_control_area * control)453 void nested_copy_vmcb_control_to_cache(struct vcpu_svm *svm,
454 struct vmcb_control_area *control)
455 {
456 __nested_copy_vmcb_control_to_cache(&svm->vcpu, &svm->nested.ctl, control);
457 }
458
__nested_copy_vmcb_save_to_cache(struct vmcb_save_area_cached * to,struct vmcb_save_area * from)459 static void __nested_copy_vmcb_save_to_cache(struct vmcb_save_area_cached *to,
460 struct vmcb_save_area *from)
461 {
462 /*
463 * Copy only fields that are validated, as we need them
464 * to avoid TOC/TOU races.
465 */
466 to->efer = from->efer;
467 to->cr0 = from->cr0;
468 to->cr3 = from->cr3;
469 to->cr4 = from->cr4;
470
471 to->dr6 = from->dr6;
472 to->dr7 = from->dr7;
473 }
474
nested_copy_vmcb_save_to_cache(struct vcpu_svm * svm,struct vmcb_save_area * save)475 void nested_copy_vmcb_save_to_cache(struct vcpu_svm *svm,
476 struct vmcb_save_area *save)
477 {
478 __nested_copy_vmcb_save_to_cache(&svm->nested.save, save);
479 }
480
481 /*
482 * Synchronize fields that are written by the processor, so that
483 * they can be copied back into the vmcb12.
484 */
nested_sync_control_from_vmcb02(struct vcpu_svm * svm)485 void nested_sync_control_from_vmcb02(struct vcpu_svm *svm)
486 {
487 u32 mask;
488 svm->nested.ctl.event_inj = svm->vmcb->control.event_inj;
489 svm->nested.ctl.event_inj_err = svm->vmcb->control.event_inj_err;
490
491 /* Only a few fields of int_ctl are written by the processor. */
492 mask = V_IRQ_MASK | V_TPR_MASK;
493 /*
494 * Don't sync vmcb02 V_IRQ back to vmcb12 if KVM (L0) is intercepting
495 * virtual interrupts in order to request an interrupt window, as KVM
496 * has usurped vmcb02's int_ctl. If an interrupt window opens before
497 * the next VM-Exit, svm_clear_vintr() will restore vmcb12's int_ctl.
498 * If no window opens, V_IRQ will be correctly preserved in vmcb12's
499 * int_ctl (because it was never recognized while L2 was running).
500 */
501 if (svm_is_intercept(svm, INTERCEPT_VINTR) &&
502 !test_bit(INTERCEPT_VINTR, (unsigned long *)svm->nested.ctl.intercepts))
503 mask &= ~V_IRQ_MASK;
504
505 if (nested_vgif_enabled(svm))
506 mask |= V_GIF_MASK;
507
508 if (nested_vnmi_enabled(svm))
509 mask |= V_NMI_BLOCKING_MASK | V_NMI_PENDING_MASK;
510
511 svm->nested.ctl.int_ctl &= ~mask;
512 svm->nested.ctl.int_ctl |= svm->vmcb->control.int_ctl & mask;
513 }
514
515 /*
516 * Transfer any event that L0 or L1 wanted to inject into L2 to
517 * EXIT_INT_INFO.
518 */
nested_save_pending_event_to_vmcb12(struct vcpu_svm * svm,struct vmcb * vmcb12)519 static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm,
520 struct vmcb *vmcb12)
521 {
522 struct kvm_vcpu *vcpu = &svm->vcpu;
523 u32 exit_int_info = 0;
524 unsigned int nr;
525
526 if (vcpu->arch.exception.injected) {
527 nr = vcpu->arch.exception.vector;
528 exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT;
529
530 if (vcpu->arch.exception.has_error_code) {
531 exit_int_info |= SVM_EVTINJ_VALID_ERR;
532 vmcb12->control.exit_int_info_err =
533 vcpu->arch.exception.error_code;
534 }
535
536 } else if (vcpu->arch.nmi_injected) {
537 exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI;
538
539 } else if (vcpu->arch.interrupt.injected) {
540 nr = vcpu->arch.interrupt.nr;
541 exit_int_info = nr | SVM_EVTINJ_VALID;
542
543 if (vcpu->arch.interrupt.soft)
544 exit_int_info |= SVM_EVTINJ_TYPE_SOFT;
545 else
546 exit_int_info |= SVM_EVTINJ_TYPE_INTR;
547 }
548
549 vmcb12->control.exit_int_info = exit_int_info;
550 }
551
nested_svm_transition_tlb_flush(struct kvm_vcpu * vcpu)552 static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu)
553 {
554 /* Handle pending Hyper-V TLB flush requests */
555 kvm_hv_nested_transtion_tlb_flush(vcpu, npt_enabled);
556
557 /*
558 * TODO: optimize unconditional TLB flush/MMU sync. A partial list of
559 * things to fix before this can be conditional:
560 *
561 * - Flush TLBs for both L1 and L2 remote TLB flush
562 * - Honor L1's request to flush an ASID on nested VMRUN
563 * - Sync nested NPT MMU on VMRUN that flushes L2's ASID[*]
564 * - Don't crush a pending TLB flush in vmcb02 on nested VMRUN
565 * - Flush L1's ASID on KVM_REQ_TLB_FLUSH_GUEST
566 *
567 * [*] Unlike nested EPT, SVM's ASID management can invalidate nested
568 * NPT guest-physical mappings on VMRUN.
569 */
570 kvm_make_request(KVM_REQ_MMU_SYNC, vcpu);
571 kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
572 }
573
574 /*
575 * Load guest's/host's cr3 on nested vmentry or vmexit. @nested_npt is true
576 * if we are emulating VM-Entry into a guest with NPT enabled.
577 */
nested_svm_load_cr3(struct kvm_vcpu * vcpu,unsigned long cr3,bool nested_npt,bool reload_pdptrs)578 static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
579 bool nested_npt, bool reload_pdptrs)
580 {
581 if (CC(!kvm_vcpu_is_legal_cr3(vcpu, cr3)))
582 return -EINVAL;
583
584 if (reload_pdptrs && !nested_npt && is_pae_paging(vcpu) &&
585 CC(!load_pdptrs(vcpu, cr3)))
586 return -EINVAL;
587
588 vcpu->arch.cr3 = cr3;
589
590 /* Re-initialize the MMU, e.g. to pick up CR4 MMU role changes. */
591 kvm_init_mmu(vcpu);
592
593 if (!nested_npt)
594 kvm_mmu_new_pgd(vcpu, cr3);
595
596 return 0;
597 }
598
nested_vmcb02_compute_g_pat(struct vcpu_svm * svm)599 void nested_vmcb02_compute_g_pat(struct vcpu_svm *svm)
600 {
601 if (!svm->nested.vmcb02.ptr)
602 return;
603
604 /* FIXME: merge g_pat from vmcb01 and vmcb12. */
605 svm->nested.vmcb02.ptr->save.g_pat = svm->vmcb01.ptr->save.g_pat;
606 }
607
nested_vmcb02_prepare_save(struct vcpu_svm * svm,struct vmcb * vmcb12)608 static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12)
609 {
610 bool new_vmcb12 = false;
611 struct vmcb *vmcb01 = svm->vmcb01.ptr;
612 struct vmcb *vmcb02 = svm->nested.vmcb02.ptr;
613 struct kvm_vcpu *vcpu = &svm->vcpu;
614
615 nested_vmcb02_compute_g_pat(svm);
616
617 /* Load the nested guest state */
618 if (svm->nested.vmcb12_gpa != svm->nested.last_vmcb12_gpa) {
619 new_vmcb12 = true;
620 svm->nested.last_vmcb12_gpa = svm->nested.vmcb12_gpa;
621 svm->nested.force_msr_bitmap_recalc = true;
622 }
623
624 if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_SEG))) {
625 vmcb02->save.es = vmcb12->save.es;
626 vmcb02->save.cs = vmcb12->save.cs;
627 vmcb02->save.ss = vmcb12->save.ss;
628 vmcb02->save.ds = vmcb12->save.ds;
629 vmcb02->save.cpl = vmcb12->save.cpl;
630 vmcb_mark_dirty(vmcb02, VMCB_SEG);
631 }
632
633 if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DT))) {
634 vmcb02->save.gdtr = vmcb12->save.gdtr;
635 vmcb02->save.idtr = vmcb12->save.idtr;
636 vmcb_mark_dirty(vmcb02, VMCB_DT);
637 }
638
639 kvm_set_rflags(vcpu, vmcb12->save.rflags | X86_EFLAGS_FIXED);
640
641 svm_set_efer(vcpu, svm->nested.save.efer);
642
643 svm_set_cr0(vcpu, svm->nested.save.cr0);
644 svm_set_cr4(vcpu, svm->nested.save.cr4);
645
646 svm->vcpu.arch.cr2 = vmcb12->save.cr2;
647
648 kvm_rax_write(vcpu, vmcb12->save.rax);
649 kvm_rsp_write(vcpu, vmcb12->save.rsp);
650 kvm_rip_write(vcpu, vmcb12->save.rip);
651
652 /* In case we don't even reach vcpu_run, the fields are not updated */
653 vmcb02->save.rax = vmcb12->save.rax;
654 vmcb02->save.rsp = vmcb12->save.rsp;
655 vmcb02->save.rip = vmcb12->save.rip;
656
657 /* These bits will be set properly on the first execution when new_vmc12 is true */
658 if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DR))) {
659 vmcb02->save.dr7 = svm->nested.save.dr7 | DR7_FIXED_1;
660 svm->vcpu.arch.dr6 = svm->nested.save.dr6 | DR6_ACTIVE_LOW;
661 vmcb_mark_dirty(vmcb02, VMCB_DR);
662 }
663
664 if (unlikely(guest_cpu_cap_has(vcpu, X86_FEATURE_LBRV) &&
665 (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) {
666 /*
667 * Reserved bits of DEBUGCTL are ignored. Be consistent with
668 * svm_set_msr's definition of reserved bits.
669 */
670 svm_copy_lbrs(vmcb02, vmcb12);
671 vmcb02->save.dbgctl &= ~DEBUGCTL_RESERVED_BITS;
672 svm_update_lbrv(&svm->vcpu);
673
674 } else if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) {
675 svm_copy_lbrs(vmcb02, vmcb01);
676 }
677 }
678
is_evtinj_soft(u32 evtinj)679 static inline bool is_evtinj_soft(u32 evtinj)
680 {
681 u32 type = evtinj & SVM_EVTINJ_TYPE_MASK;
682 u8 vector = evtinj & SVM_EVTINJ_VEC_MASK;
683
684 if (!(evtinj & SVM_EVTINJ_VALID))
685 return false;
686
687 if (type == SVM_EVTINJ_TYPE_SOFT)
688 return true;
689
690 return type == SVM_EVTINJ_TYPE_EXEPT && kvm_exception_is_soft(vector);
691 }
692
is_evtinj_nmi(u32 evtinj)693 static bool is_evtinj_nmi(u32 evtinj)
694 {
695 u32 type = evtinj & SVM_EVTINJ_TYPE_MASK;
696
697 if (!(evtinj & SVM_EVTINJ_VALID))
698 return false;
699
700 return type == SVM_EVTINJ_TYPE_NMI;
701 }
702
nested_vmcb02_prepare_control(struct vcpu_svm * svm,unsigned long vmcb12_rip,unsigned long vmcb12_csbase)703 static void nested_vmcb02_prepare_control(struct vcpu_svm *svm,
704 unsigned long vmcb12_rip,
705 unsigned long vmcb12_csbase)
706 {
707 u32 int_ctl_vmcb01_bits = V_INTR_MASKING_MASK;
708 u32 int_ctl_vmcb12_bits = V_TPR_MASK | V_IRQ_INJECTION_BITS_MASK;
709
710 struct kvm_vcpu *vcpu = &svm->vcpu;
711 struct vmcb *vmcb01 = svm->vmcb01.ptr;
712 struct vmcb *vmcb02 = svm->nested.vmcb02.ptr;
713 u32 pause_count12;
714 u32 pause_thresh12;
715
716 nested_svm_transition_tlb_flush(vcpu);
717
718 /* Enter Guest-Mode */
719 enter_guest_mode(vcpu);
720
721 /*
722 * Filled at exit: exit_code, exit_code_hi, exit_info_1, exit_info_2,
723 * exit_int_info, exit_int_info_err, next_rip, insn_len, insn_bytes.
724 */
725
726 if (guest_cpu_cap_has(vcpu, X86_FEATURE_VGIF) &&
727 (svm->nested.ctl.int_ctl & V_GIF_ENABLE_MASK))
728 int_ctl_vmcb12_bits |= (V_GIF_MASK | V_GIF_ENABLE_MASK);
729 else
730 int_ctl_vmcb01_bits |= (V_GIF_MASK | V_GIF_ENABLE_MASK);
731
732 if (vnmi) {
733 if (vmcb01->control.int_ctl & V_NMI_PENDING_MASK) {
734 svm->vcpu.arch.nmi_pending++;
735 kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
736 }
737 if (nested_vnmi_enabled(svm))
738 int_ctl_vmcb12_bits |= (V_NMI_PENDING_MASK |
739 V_NMI_ENABLE_MASK |
740 V_NMI_BLOCKING_MASK);
741 }
742
743 /* Copied from vmcb01. msrpm_base can be overwritten later. */
744 vmcb02->control.nested_ctl = vmcb01->control.nested_ctl;
745 vmcb02->control.iopm_base_pa = vmcb01->control.iopm_base_pa;
746 vmcb02->control.msrpm_base_pa = vmcb01->control.msrpm_base_pa;
747
748 /*
749 * Stash vmcb02's counter if the guest hasn't moved past the guilty
750 * instruction; otherwise, reset the counter to '0'.
751 *
752 * In order to detect if L2 has made forward progress or not, track the
753 * RIP at which a bus lock has occurred on a per-vmcb12 basis. If RIP
754 * is changed, guest has clearly made forward progress, bus_lock_counter
755 * still remained '1', so reset bus_lock_counter to '0'. Eg. In the
756 * scenario, where a buslock happened in L1 before VMRUN, the bus lock
757 * firmly happened on an instruction in the past. Even if vmcb01's
758 * counter is still '1', (because the guilty instruction got patched),
759 * the vCPU has clearly made forward progress and so KVM should reset
760 * vmcb02's counter to '0'.
761 *
762 * If the RIP hasn't changed, stash the bus lock counter at nested VMRUN
763 * to prevent the same guilty instruction from triggering a VM-Exit. Eg.
764 * if userspace rate-limits the vCPU, then it's entirely possible that
765 * L1's tick interrupt is pending by the time userspace re-runs the
766 * vCPU. If KVM unconditionally clears the counter on VMRUN, then when
767 * L1 re-enters L2, the same instruction will trigger a VM-Exit and the
768 * entire cycle start over.
769 */
770 if (vmcb02->save.rip && (svm->nested.ctl.bus_lock_rip == vmcb02->save.rip))
771 vmcb02->control.bus_lock_counter = 1;
772 else
773 vmcb02->control.bus_lock_counter = 0;
774
775 /* Done at vmrun: asid. */
776
777 /* Also overwritten later if necessary. */
778 vmcb02->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
779
780 /* nested_cr3. */
781 if (nested_npt_enabled(svm))
782 nested_svm_init_mmu_context(vcpu);
783
784 vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset(
785 vcpu->arch.l1_tsc_offset,
786 svm->nested.ctl.tsc_offset,
787 svm->tsc_ratio_msr);
788
789 vmcb02->control.tsc_offset = vcpu->arch.tsc_offset;
790
791 if (guest_cpu_cap_has(vcpu, X86_FEATURE_TSCRATEMSR) &&
792 svm->tsc_ratio_msr != kvm_caps.default_tsc_scaling_ratio)
793 nested_svm_update_tsc_ratio_msr(vcpu);
794
795 vmcb02->control.int_ctl =
796 (svm->nested.ctl.int_ctl & int_ctl_vmcb12_bits) |
797 (vmcb01->control.int_ctl & int_ctl_vmcb01_bits);
798
799 vmcb02->control.int_vector = svm->nested.ctl.int_vector;
800 vmcb02->control.int_state = svm->nested.ctl.int_state;
801 vmcb02->control.event_inj = svm->nested.ctl.event_inj;
802 vmcb02->control.event_inj_err = svm->nested.ctl.event_inj_err;
803
804 /*
805 * next_rip is consumed on VMRUN as the return address pushed on the
806 * stack for injected soft exceptions/interrupts. If nrips is exposed
807 * to L1, take it verbatim from vmcb12. If nrips is supported in
808 * hardware but not exposed to L1, stuff the actual L2 RIP to emulate
809 * what a nrips=0 CPU would do (L1 is responsible for advancing RIP
810 * prior to injecting the event).
811 */
812 if (guest_cpu_cap_has(vcpu, X86_FEATURE_NRIPS))
813 vmcb02->control.next_rip = svm->nested.ctl.next_rip;
814 else if (boot_cpu_has(X86_FEATURE_NRIPS))
815 vmcb02->control.next_rip = vmcb12_rip;
816
817 svm->nmi_l1_to_l2 = is_evtinj_nmi(vmcb02->control.event_inj);
818 if (is_evtinj_soft(vmcb02->control.event_inj)) {
819 svm->soft_int_injected = true;
820 svm->soft_int_csbase = vmcb12_csbase;
821 svm->soft_int_old_rip = vmcb12_rip;
822 if (guest_cpu_cap_has(vcpu, X86_FEATURE_NRIPS))
823 svm->soft_int_next_rip = svm->nested.ctl.next_rip;
824 else
825 svm->soft_int_next_rip = vmcb12_rip;
826 }
827
828 vmcb02->control.virt_ext = vmcb01->control.virt_ext &
829 LBR_CTL_ENABLE_MASK;
830 if (guest_cpu_cap_has(vcpu, X86_FEATURE_LBRV))
831 vmcb02->control.virt_ext |=
832 (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK);
833
834 if (!nested_vmcb_needs_vls_intercept(svm))
835 vmcb02->control.virt_ext |= VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK;
836
837 if (guest_cpu_cap_has(vcpu, X86_FEATURE_PAUSEFILTER))
838 pause_count12 = svm->nested.ctl.pause_filter_count;
839 else
840 pause_count12 = 0;
841 if (guest_cpu_cap_has(vcpu, X86_FEATURE_PFTHRESHOLD))
842 pause_thresh12 = svm->nested.ctl.pause_filter_thresh;
843 else
844 pause_thresh12 = 0;
845 if (kvm_pause_in_guest(svm->vcpu.kvm)) {
846 /* use guest values since host doesn't intercept PAUSE */
847 vmcb02->control.pause_filter_count = pause_count12;
848 vmcb02->control.pause_filter_thresh = pause_thresh12;
849
850 } else {
851 /* start from host values otherwise */
852 vmcb02->control.pause_filter_count = vmcb01->control.pause_filter_count;
853 vmcb02->control.pause_filter_thresh = vmcb01->control.pause_filter_thresh;
854
855 /* ... but ensure filtering is disabled if so requested. */
856 if (vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_PAUSE)) {
857 if (!pause_count12)
858 vmcb02->control.pause_filter_count = 0;
859 if (!pause_thresh12)
860 vmcb02->control.pause_filter_thresh = 0;
861 }
862 }
863
864 /*
865 * Merge guest and host intercepts - must be called with vcpu in
866 * guest-mode to take effect.
867 */
868 recalc_intercepts(svm);
869 }
870
nested_svm_copy_common_state(struct vmcb * from_vmcb,struct vmcb * to_vmcb)871 static void nested_svm_copy_common_state(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
872 {
873 /*
874 * Some VMCB state is shared between L1 and L2 and thus has to be
875 * moved at the time of nested vmrun and vmexit.
876 *
877 * VMLOAD/VMSAVE state would also belong in this category, but KVM
878 * always performs VMLOAD and VMSAVE from the VMCB01.
879 */
880 to_vmcb->save.spec_ctrl = from_vmcb->save.spec_ctrl;
881 }
882
enter_svm_guest_mode(struct kvm_vcpu * vcpu,u64 vmcb12_gpa,struct vmcb * vmcb12,bool from_vmrun)883 int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa,
884 struct vmcb *vmcb12, bool from_vmrun)
885 {
886 struct vcpu_svm *svm = to_svm(vcpu);
887 int ret;
888
889 trace_kvm_nested_vmenter(svm->vmcb->save.rip,
890 vmcb12_gpa,
891 vmcb12->save.rip,
892 vmcb12->control.int_ctl,
893 vmcb12->control.event_inj,
894 vmcb12->control.nested_ctl,
895 vmcb12->control.nested_cr3,
896 vmcb12->save.cr3,
897 KVM_ISA_SVM);
898
899 trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff,
900 vmcb12->control.intercepts[INTERCEPT_CR] >> 16,
901 vmcb12->control.intercepts[INTERCEPT_EXCEPTION],
902 vmcb12->control.intercepts[INTERCEPT_WORD3],
903 vmcb12->control.intercepts[INTERCEPT_WORD4],
904 vmcb12->control.intercepts[INTERCEPT_WORD5]);
905
906
907 svm->nested.vmcb12_gpa = vmcb12_gpa;
908
909 WARN_ON(svm->vmcb == svm->nested.vmcb02.ptr);
910
911 nested_svm_copy_common_state(svm->vmcb01.ptr, svm->nested.vmcb02.ptr);
912
913 svm_switch_vmcb(svm, &svm->nested.vmcb02);
914 nested_vmcb02_prepare_control(svm, vmcb12->save.rip, vmcb12->save.cs.base);
915 nested_vmcb02_prepare_save(svm, vmcb12);
916
917 ret = nested_svm_load_cr3(&svm->vcpu, svm->nested.save.cr3,
918 nested_npt_enabled(svm), from_vmrun);
919 if (ret)
920 return ret;
921
922 if (!from_vmrun)
923 kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
924
925 svm_set_gif(svm, true);
926
927 if (kvm_vcpu_apicv_active(vcpu))
928 kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
929
930 nested_svm_hv_update_vm_vp_ids(vcpu);
931
932 return 0;
933 }
934
nested_svm_vmrun(struct kvm_vcpu * vcpu)935 int nested_svm_vmrun(struct kvm_vcpu *vcpu)
936 {
937 struct vcpu_svm *svm = to_svm(vcpu);
938 int ret;
939 struct vmcb *vmcb12;
940 struct kvm_host_map map;
941 u64 vmcb12_gpa;
942 struct vmcb *vmcb01 = svm->vmcb01.ptr;
943
944 if (!svm->nested.hsave_msr) {
945 kvm_inject_gp(vcpu, 0);
946 return 1;
947 }
948
949 if (is_smm(vcpu)) {
950 kvm_queue_exception(vcpu, UD_VECTOR);
951 return 1;
952 }
953
954 /* This fails when VP assist page is enabled but the supplied GPA is bogus */
955 ret = kvm_hv_verify_vp_assist(vcpu);
956 if (ret) {
957 kvm_inject_gp(vcpu, 0);
958 return ret;
959 }
960
961 vmcb12_gpa = svm->vmcb->save.rax;
962 ret = kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map);
963 if (ret == -EINVAL) {
964 kvm_inject_gp(vcpu, 0);
965 return 1;
966 } else if (ret) {
967 return kvm_skip_emulated_instruction(vcpu);
968 }
969
970 ret = kvm_skip_emulated_instruction(vcpu);
971
972 vmcb12 = map.hva;
973
974 if (WARN_ON_ONCE(!svm->nested.initialized))
975 return -EINVAL;
976
977 nested_copy_vmcb_control_to_cache(svm, &vmcb12->control);
978 nested_copy_vmcb_save_to_cache(svm, &vmcb12->save);
979
980 if (!nested_vmcb_check_save(vcpu) ||
981 !nested_vmcb_check_controls(vcpu)) {
982 vmcb12->control.exit_code = SVM_EXIT_ERR;
983 vmcb12->control.exit_code_hi = 0;
984 vmcb12->control.exit_info_1 = 0;
985 vmcb12->control.exit_info_2 = 0;
986 goto out;
987 }
988
989 /*
990 * Since vmcb01 is not in use, we can use it to store some of the L1
991 * state.
992 */
993 vmcb01->save.efer = vcpu->arch.efer;
994 vmcb01->save.cr0 = kvm_read_cr0(vcpu);
995 vmcb01->save.cr4 = vcpu->arch.cr4;
996 vmcb01->save.rflags = kvm_get_rflags(vcpu);
997 vmcb01->save.rip = kvm_rip_read(vcpu);
998
999 if (!npt_enabled)
1000 vmcb01->save.cr3 = kvm_read_cr3(vcpu);
1001
1002 svm->nested.nested_run_pending = 1;
1003
1004 if (enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12, true))
1005 goto out_exit_err;
1006
1007 if (nested_svm_merge_msrpm(vcpu))
1008 goto out;
1009
1010 out_exit_err:
1011 svm->nested.nested_run_pending = 0;
1012 svm->nmi_l1_to_l2 = false;
1013 svm->soft_int_injected = false;
1014
1015 svm->vmcb->control.exit_code = SVM_EXIT_ERR;
1016 svm->vmcb->control.exit_code_hi = 0;
1017 svm->vmcb->control.exit_info_1 = 0;
1018 svm->vmcb->control.exit_info_2 = 0;
1019
1020 nested_svm_vmexit(svm);
1021
1022 out:
1023 kvm_vcpu_unmap(vcpu, &map);
1024
1025 return ret;
1026 }
1027
1028 /* Copy state save area fields which are handled by VMRUN */
svm_copy_vmrun_state(struct vmcb_save_area * to_save,struct vmcb_save_area * from_save)1029 void svm_copy_vmrun_state(struct vmcb_save_area *to_save,
1030 struct vmcb_save_area *from_save)
1031 {
1032 to_save->es = from_save->es;
1033 to_save->cs = from_save->cs;
1034 to_save->ss = from_save->ss;
1035 to_save->ds = from_save->ds;
1036 to_save->gdtr = from_save->gdtr;
1037 to_save->idtr = from_save->idtr;
1038 to_save->rflags = from_save->rflags | X86_EFLAGS_FIXED;
1039 to_save->efer = from_save->efer;
1040 to_save->cr0 = from_save->cr0;
1041 to_save->cr3 = from_save->cr3;
1042 to_save->cr4 = from_save->cr4;
1043 to_save->rax = from_save->rax;
1044 to_save->rsp = from_save->rsp;
1045 to_save->rip = from_save->rip;
1046 to_save->cpl = 0;
1047 }
1048
svm_copy_vmloadsave_state(struct vmcb * to_vmcb,struct vmcb * from_vmcb)1049 void svm_copy_vmloadsave_state(struct vmcb *to_vmcb, struct vmcb *from_vmcb)
1050 {
1051 to_vmcb->save.fs = from_vmcb->save.fs;
1052 to_vmcb->save.gs = from_vmcb->save.gs;
1053 to_vmcb->save.tr = from_vmcb->save.tr;
1054 to_vmcb->save.ldtr = from_vmcb->save.ldtr;
1055 to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
1056 to_vmcb->save.star = from_vmcb->save.star;
1057 to_vmcb->save.lstar = from_vmcb->save.lstar;
1058 to_vmcb->save.cstar = from_vmcb->save.cstar;
1059 to_vmcb->save.sfmask = from_vmcb->save.sfmask;
1060 to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
1061 to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
1062 to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
1063 }
1064
nested_svm_vmexit(struct vcpu_svm * svm)1065 int nested_svm_vmexit(struct vcpu_svm *svm)
1066 {
1067 struct kvm_vcpu *vcpu = &svm->vcpu;
1068 struct vmcb *vmcb01 = svm->vmcb01.ptr;
1069 struct vmcb *vmcb02 = svm->nested.vmcb02.ptr;
1070 struct vmcb *vmcb12;
1071 struct kvm_host_map map;
1072 int rc;
1073
1074 rc = kvm_vcpu_map(vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map);
1075 if (rc) {
1076 if (rc == -EINVAL)
1077 kvm_inject_gp(vcpu, 0);
1078 return 1;
1079 }
1080
1081 vmcb12 = map.hva;
1082
1083 /* Exit Guest-Mode */
1084 leave_guest_mode(vcpu);
1085 svm->nested.vmcb12_gpa = 0;
1086 WARN_ON_ONCE(svm->nested.nested_run_pending);
1087
1088 kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1089
1090 /* in case we halted in L2 */
1091 kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
1092
1093 /* Give the current vmcb to the guest */
1094
1095 vmcb12->save.es = vmcb02->save.es;
1096 vmcb12->save.cs = vmcb02->save.cs;
1097 vmcb12->save.ss = vmcb02->save.ss;
1098 vmcb12->save.ds = vmcb02->save.ds;
1099 vmcb12->save.gdtr = vmcb02->save.gdtr;
1100 vmcb12->save.idtr = vmcb02->save.idtr;
1101 vmcb12->save.efer = svm->vcpu.arch.efer;
1102 vmcb12->save.cr0 = kvm_read_cr0(vcpu);
1103 vmcb12->save.cr3 = kvm_read_cr3(vcpu);
1104 vmcb12->save.cr2 = vmcb02->save.cr2;
1105 vmcb12->save.cr4 = svm->vcpu.arch.cr4;
1106 vmcb12->save.rflags = kvm_get_rflags(vcpu);
1107 vmcb12->save.rip = kvm_rip_read(vcpu);
1108 vmcb12->save.rsp = kvm_rsp_read(vcpu);
1109 vmcb12->save.rax = kvm_rax_read(vcpu);
1110 vmcb12->save.dr7 = vmcb02->save.dr7;
1111 vmcb12->save.dr6 = svm->vcpu.arch.dr6;
1112 vmcb12->save.cpl = vmcb02->save.cpl;
1113
1114 vmcb12->control.int_state = vmcb02->control.int_state;
1115 vmcb12->control.exit_code = vmcb02->control.exit_code;
1116 vmcb12->control.exit_code_hi = vmcb02->control.exit_code_hi;
1117 vmcb12->control.exit_info_1 = vmcb02->control.exit_info_1;
1118 vmcb12->control.exit_info_2 = vmcb02->control.exit_info_2;
1119
1120 if (vmcb12->control.exit_code != SVM_EXIT_ERR)
1121 nested_save_pending_event_to_vmcb12(svm, vmcb12);
1122
1123 if (guest_cpu_cap_has(vcpu, X86_FEATURE_NRIPS))
1124 vmcb12->control.next_rip = vmcb02->control.next_rip;
1125
1126 vmcb12->control.int_ctl = svm->nested.ctl.int_ctl;
1127 vmcb12->control.event_inj = svm->nested.ctl.event_inj;
1128 vmcb12->control.event_inj_err = svm->nested.ctl.event_inj_err;
1129
1130 if (!kvm_pause_in_guest(vcpu->kvm)) {
1131 vmcb01->control.pause_filter_count = vmcb02->control.pause_filter_count;
1132 vmcb_mark_dirty(vmcb01, VMCB_INTERCEPTS);
1133
1134 }
1135
1136 /*
1137 * Invalidate bus_lock_rip unless KVM is still waiting for the guest
1138 * to make forward progress before re-enabling bus lock detection.
1139 */
1140 if (!vmcb02->control.bus_lock_counter)
1141 svm->nested.ctl.bus_lock_rip = INVALID_GPA;
1142
1143 nested_svm_copy_common_state(svm->nested.vmcb02.ptr, svm->vmcb01.ptr);
1144
1145 kvm_nested_vmexit_handle_ibrs(vcpu);
1146
1147 svm_switch_vmcb(svm, &svm->vmcb01);
1148
1149 /*
1150 * Rules for synchronizing int_ctl bits from vmcb02 to vmcb01:
1151 *
1152 * V_IRQ, V_IRQ_VECTOR, V_INTR_PRIO_MASK, V_IGN_TPR: If L1 doesn't
1153 * intercept interrupts, then KVM will use vmcb02's V_IRQ (and related
1154 * flags) to detect interrupt windows for L1 IRQs (even if L1 uses
1155 * virtual interrupt masking). Raise KVM_REQ_EVENT to ensure that
1156 * KVM re-requests an interrupt window if necessary, which implicitly
1157 * copies this bits from vmcb02 to vmcb01.
1158 *
1159 * V_TPR: If L1 doesn't use virtual interrupt masking, then L1's vTPR
1160 * is stored in vmcb02, but its value doesn't need to be copied from/to
1161 * vmcb01 because it is copied from/to the virtual APIC's TPR register
1162 * on each VM entry/exit.
1163 *
1164 * V_GIF: If nested vGIF is not used, KVM uses vmcb02's V_GIF for L1's
1165 * V_GIF. However, GIF is architecturally clear on each VM exit, thus
1166 * there is no need to copy V_GIF from vmcb02 to vmcb01.
1167 */
1168 if (!nested_exit_on_intr(svm))
1169 kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
1170
1171 if (unlikely(guest_cpu_cap_has(vcpu, X86_FEATURE_LBRV) &&
1172 (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) {
1173 svm_copy_lbrs(vmcb12, vmcb02);
1174 svm_update_lbrv(vcpu);
1175 } else if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) {
1176 svm_copy_lbrs(vmcb01, vmcb02);
1177 svm_update_lbrv(vcpu);
1178 }
1179
1180 if (vnmi) {
1181 if (vmcb02->control.int_ctl & V_NMI_BLOCKING_MASK)
1182 vmcb01->control.int_ctl |= V_NMI_BLOCKING_MASK;
1183 else
1184 vmcb01->control.int_ctl &= ~V_NMI_BLOCKING_MASK;
1185
1186 if (vcpu->arch.nmi_pending) {
1187 vcpu->arch.nmi_pending--;
1188 vmcb01->control.int_ctl |= V_NMI_PENDING_MASK;
1189 } else {
1190 vmcb01->control.int_ctl &= ~V_NMI_PENDING_MASK;
1191 }
1192 }
1193
1194 /*
1195 * On vmexit the GIF is set to false and
1196 * no event can be injected in L1.
1197 */
1198 svm_set_gif(svm, false);
1199 vmcb01->control.exit_int_info = 0;
1200
1201 svm->vcpu.arch.tsc_offset = svm->vcpu.arch.l1_tsc_offset;
1202 if (vmcb01->control.tsc_offset != svm->vcpu.arch.tsc_offset) {
1203 vmcb01->control.tsc_offset = svm->vcpu.arch.tsc_offset;
1204 vmcb_mark_dirty(vmcb01, VMCB_INTERCEPTS);
1205 }
1206
1207 if (kvm_caps.has_tsc_control &&
1208 vcpu->arch.tsc_scaling_ratio != vcpu->arch.l1_tsc_scaling_ratio) {
1209 vcpu->arch.tsc_scaling_ratio = vcpu->arch.l1_tsc_scaling_ratio;
1210 svm_write_tsc_multiplier(vcpu);
1211 }
1212
1213 svm->nested.ctl.nested_cr3 = 0;
1214
1215 /*
1216 * Restore processor state that had been saved in vmcb01
1217 */
1218 kvm_set_rflags(vcpu, vmcb01->save.rflags);
1219 svm_set_efer(vcpu, vmcb01->save.efer);
1220 svm_set_cr0(vcpu, vmcb01->save.cr0 | X86_CR0_PE);
1221 svm_set_cr4(vcpu, vmcb01->save.cr4);
1222 kvm_rax_write(vcpu, vmcb01->save.rax);
1223 kvm_rsp_write(vcpu, vmcb01->save.rsp);
1224 kvm_rip_write(vcpu, vmcb01->save.rip);
1225
1226 svm->vcpu.arch.dr7 = DR7_FIXED_1;
1227 kvm_update_dr7(&svm->vcpu);
1228
1229 trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code,
1230 vmcb12->control.exit_info_1,
1231 vmcb12->control.exit_info_2,
1232 vmcb12->control.exit_int_info,
1233 vmcb12->control.exit_int_info_err,
1234 KVM_ISA_SVM);
1235
1236 kvm_vcpu_unmap(vcpu, &map);
1237
1238 nested_svm_transition_tlb_flush(vcpu);
1239
1240 nested_svm_uninit_mmu_context(vcpu);
1241
1242 rc = nested_svm_load_cr3(vcpu, vmcb01->save.cr3, false, true);
1243 if (rc)
1244 return 1;
1245
1246 /*
1247 * Drop what we picked up for L2 via svm_complete_interrupts() so it
1248 * doesn't end up in L1.
1249 */
1250 svm->vcpu.arch.nmi_injected = false;
1251 kvm_clear_exception_queue(vcpu);
1252 kvm_clear_interrupt_queue(vcpu);
1253
1254 /*
1255 * If we are here following the completion of a VMRUN that
1256 * is being single-stepped, queue the pending #DB intercept
1257 * right now so that it an be accounted for before we execute
1258 * L1's next instruction.
1259 */
1260 if (unlikely(vmcb01->save.rflags & X86_EFLAGS_TF))
1261 kvm_queue_exception(&(svm->vcpu), DB_VECTOR);
1262
1263 /*
1264 * Un-inhibit the AVIC right away, so that other vCPUs can start
1265 * to benefit from it right away.
1266 */
1267 if (kvm_apicv_activated(vcpu->kvm))
1268 __kvm_vcpu_update_apicv(vcpu);
1269
1270 return 0;
1271 }
1272
nested_svm_triple_fault(struct kvm_vcpu * vcpu)1273 static void nested_svm_triple_fault(struct kvm_vcpu *vcpu)
1274 {
1275 struct vcpu_svm *svm = to_svm(vcpu);
1276
1277 if (!vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_SHUTDOWN))
1278 return;
1279
1280 kvm_clear_request(KVM_REQ_TRIPLE_FAULT, vcpu);
1281 nested_svm_simple_vmexit(to_svm(vcpu), SVM_EXIT_SHUTDOWN);
1282 }
1283
svm_allocate_nested(struct vcpu_svm * svm)1284 int svm_allocate_nested(struct vcpu_svm *svm)
1285 {
1286 struct page *vmcb02_page;
1287
1288 if (svm->nested.initialized)
1289 return 0;
1290
1291 vmcb02_page = snp_safe_alloc_page();
1292 if (!vmcb02_page)
1293 return -ENOMEM;
1294 svm->nested.vmcb02.ptr = page_address(vmcb02_page);
1295 svm->nested.vmcb02.pa = __sme_set(page_to_pfn(vmcb02_page) << PAGE_SHIFT);
1296
1297 svm->nested.msrpm = svm_vcpu_alloc_msrpm();
1298 if (!svm->nested.msrpm)
1299 goto err_free_vmcb02;
1300
1301 svm->nested.initialized = true;
1302 return 0;
1303
1304 err_free_vmcb02:
1305 __free_page(vmcb02_page);
1306 return -ENOMEM;
1307 }
1308
svm_free_nested(struct vcpu_svm * svm)1309 void svm_free_nested(struct vcpu_svm *svm)
1310 {
1311 if (!svm->nested.initialized)
1312 return;
1313
1314 if (WARN_ON_ONCE(svm->vmcb != svm->vmcb01.ptr))
1315 svm_switch_vmcb(svm, &svm->vmcb01);
1316
1317 svm_vcpu_free_msrpm(svm->nested.msrpm);
1318 svm->nested.msrpm = NULL;
1319
1320 __free_page(virt_to_page(svm->nested.vmcb02.ptr));
1321 svm->nested.vmcb02.ptr = NULL;
1322
1323 /*
1324 * When last_vmcb12_gpa matches the current vmcb12 gpa,
1325 * some vmcb12 fields are not loaded if they are marked clean
1326 * in the vmcb12, since in this case they are up to date already.
1327 *
1328 * When the vmcb02 is freed, this optimization becomes invalid.
1329 */
1330 svm->nested.last_vmcb12_gpa = INVALID_GPA;
1331
1332 svm->nested.initialized = false;
1333 }
1334
svm_leave_nested(struct kvm_vcpu * vcpu)1335 void svm_leave_nested(struct kvm_vcpu *vcpu)
1336 {
1337 struct vcpu_svm *svm = to_svm(vcpu);
1338
1339 if (is_guest_mode(vcpu)) {
1340 svm->nested.nested_run_pending = 0;
1341 svm->nested.vmcb12_gpa = INVALID_GPA;
1342
1343 leave_guest_mode(vcpu);
1344
1345 svm_switch_vmcb(svm, &svm->vmcb01);
1346
1347 nested_svm_uninit_mmu_context(vcpu);
1348 vmcb_mark_all_dirty(svm->vmcb);
1349
1350 if (kvm_apicv_activated(vcpu->kvm))
1351 kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
1352 }
1353
1354 kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1355 }
1356
nested_svm_exit_handled_msr(struct vcpu_svm * svm)1357 static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
1358 {
1359 gpa_t base = svm->nested.ctl.msrpm_base_pa;
1360 int write, bit_nr;
1361 u8 value, mask;
1362 u32 msr;
1363
1364 if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
1365 return NESTED_EXIT_HOST;
1366
1367 msr = svm->vcpu.arch.regs[VCPU_REGS_RCX];
1368 bit_nr = svm_msrpm_bit_nr(msr);
1369 write = svm->vmcb->control.exit_info_1 & 1;
1370
1371 if (bit_nr < 0)
1372 return NESTED_EXIT_DONE;
1373
1374 if (kvm_vcpu_read_guest(&svm->vcpu, base + bit_nr / BITS_PER_BYTE,
1375 &value, sizeof(value)))
1376 return NESTED_EXIT_DONE;
1377
1378 mask = BIT(write) << (bit_nr & (BITS_PER_BYTE - 1));
1379 return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
1380 }
1381
nested_svm_intercept_ioio(struct vcpu_svm * svm)1382 static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
1383 {
1384 unsigned port, size, iopm_len;
1385 u16 val, mask;
1386 u8 start_bit;
1387 u64 gpa;
1388
1389 if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
1390 return NESTED_EXIT_HOST;
1391
1392 port = svm->vmcb->control.exit_info_1 >> 16;
1393 size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >>
1394 SVM_IOIO_SIZE_SHIFT;
1395 gpa = svm->nested.ctl.iopm_base_pa + (port / 8);
1396 start_bit = port % 8;
1397 iopm_len = (start_bit + size > 8) ? 2 : 1;
1398 mask = (0xf >> (4 - size)) << start_bit;
1399 val = 0;
1400
1401 if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len))
1402 return NESTED_EXIT_DONE;
1403
1404 return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
1405 }
1406
nested_svm_intercept(struct vcpu_svm * svm)1407 static int nested_svm_intercept(struct vcpu_svm *svm)
1408 {
1409 u32 exit_code = svm->vmcb->control.exit_code;
1410 int vmexit = NESTED_EXIT_HOST;
1411
1412 switch (exit_code) {
1413 case SVM_EXIT_MSR:
1414 vmexit = nested_svm_exit_handled_msr(svm);
1415 break;
1416 case SVM_EXIT_IOIO:
1417 vmexit = nested_svm_intercept_ioio(svm);
1418 break;
1419 case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
1420 if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
1421 vmexit = NESTED_EXIT_DONE;
1422 break;
1423 }
1424 case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
1425 if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
1426 vmexit = NESTED_EXIT_DONE;
1427 break;
1428 }
1429 case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1430 /*
1431 * Host-intercepted exceptions have been checked already in
1432 * nested_svm_exit_special. There is nothing to do here,
1433 * the vmexit is injected by svm_check_nested_events.
1434 */
1435 vmexit = NESTED_EXIT_DONE;
1436 break;
1437 }
1438 case SVM_EXIT_ERR: {
1439 vmexit = NESTED_EXIT_DONE;
1440 break;
1441 }
1442 default: {
1443 if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
1444 vmexit = NESTED_EXIT_DONE;
1445 }
1446 }
1447
1448 return vmexit;
1449 }
1450
nested_svm_exit_handled(struct vcpu_svm * svm)1451 int nested_svm_exit_handled(struct vcpu_svm *svm)
1452 {
1453 int vmexit;
1454
1455 vmexit = nested_svm_intercept(svm);
1456
1457 if (vmexit == NESTED_EXIT_DONE)
1458 nested_svm_vmexit(svm);
1459
1460 return vmexit;
1461 }
1462
nested_svm_check_permissions(struct kvm_vcpu * vcpu)1463 int nested_svm_check_permissions(struct kvm_vcpu *vcpu)
1464 {
1465 if (!(vcpu->arch.efer & EFER_SVME) || !is_paging(vcpu)) {
1466 kvm_queue_exception(vcpu, UD_VECTOR);
1467 return 1;
1468 }
1469
1470 if (to_svm(vcpu)->vmcb->save.cpl) {
1471 kvm_inject_gp(vcpu, 0);
1472 return 1;
1473 }
1474
1475 return 0;
1476 }
1477
nested_svm_is_exception_vmexit(struct kvm_vcpu * vcpu,u8 vector,u32 error_code)1478 static bool nested_svm_is_exception_vmexit(struct kvm_vcpu *vcpu, u8 vector,
1479 u32 error_code)
1480 {
1481 struct vcpu_svm *svm = to_svm(vcpu);
1482
1483 return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(vector));
1484 }
1485
nested_svm_inject_exception_vmexit(struct kvm_vcpu * vcpu)1486 static void nested_svm_inject_exception_vmexit(struct kvm_vcpu *vcpu)
1487 {
1488 struct kvm_queued_exception *ex = &vcpu->arch.exception_vmexit;
1489 struct vcpu_svm *svm = to_svm(vcpu);
1490 struct vmcb *vmcb = svm->vmcb;
1491
1492 vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + ex->vector;
1493 vmcb->control.exit_code_hi = 0;
1494
1495 if (ex->has_error_code)
1496 vmcb->control.exit_info_1 = ex->error_code;
1497
1498 /*
1499 * EXITINFO2 is undefined for all exception intercepts other
1500 * than #PF.
1501 */
1502 if (ex->vector == PF_VECTOR) {
1503 if (ex->has_payload)
1504 vmcb->control.exit_info_2 = ex->payload;
1505 else
1506 vmcb->control.exit_info_2 = vcpu->arch.cr2;
1507 } else if (ex->vector == DB_VECTOR) {
1508 /* See kvm_check_and_inject_events(). */
1509 kvm_deliver_exception_payload(vcpu, ex);
1510
1511 if (vcpu->arch.dr7 & DR7_GD) {
1512 vcpu->arch.dr7 &= ~DR7_GD;
1513 kvm_update_dr7(vcpu);
1514 }
1515 } else {
1516 WARN_ON(ex->has_payload);
1517 }
1518
1519 nested_svm_vmexit(svm);
1520 }
1521
nested_exit_on_init(struct vcpu_svm * svm)1522 static inline bool nested_exit_on_init(struct vcpu_svm *svm)
1523 {
1524 return vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
1525 }
1526
svm_check_nested_events(struct kvm_vcpu * vcpu)1527 static int svm_check_nested_events(struct kvm_vcpu *vcpu)
1528 {
1529 struct kvm_lapic *apic = vcpu->arch.apic;
1530 struct vcpu_svm *svm = to_svm(vcpu);
1531 /*
1532 * Only a pending nested run blocks a pending exception. If there is a
1533 * previously injected event, the pending exception occurred while said
1534 * event was being delivered and thus needs to be handled.
1535 */
1536 bool block_nested_exceptions = svm->nested.nested_run_pending;
1537 /*
1538 * New events (not exceptions) are only recognized at instruction
1539 * boundaries. If an event needs reinjection, then KVM is handling a
1540 * VM-Exit that occurred _during_ instruction execution; new events are
1541 * blocked until the instruction completes.
1542 */
1543 bool block_nested_events = block_nested_exceptions ||
1544 kvm_event_needs_reinjection(vcpu);
1545
1546 if (lapic_in_kernel(vcpu) &&
1547 test_bit(KVM_APIC_INIT, &apic->pending_events)) {
1548 if (block_nested_events)
1549 return -EBUSY;
1550 if (!nested_exit_on_init(svm))
1551 return 0;
1552 nested_svm_simple_vmexit(svm, SVM_EXIT_INIT);
1553 return 0;
1554 }
1555
1556 if (vcpu->arch.exception_vmexit.pending) {
1557 if (block_nested_exceptions)
1558 return -EBUSY;
1559 nested_svm_inject_exception_vmexit(vcpu);
1560 return 0;
1561 }
1562
1563 if (vcpu->arch.exception.pending) {
1564 if (block_nested_exceptions)
1565 return -EBUSY;
1566 return 0;
1567 }
1568
1569 #ifdef CONFIG_KVM_SMM
1570 if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
1571 if (block_nested_events)
1572 return -EBUSY;
1573 if (!nested_exit_on_smi(svm))
1574 return 0;
1575 nested_svm_simple_vmexit(svm, SVM_EXIT_SMI);
1576 return 0;
1577 }
1578 #endif
1579
1580 if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
1581 if (block_nested_events)
1582 return -EBUSY;
1583 if (!nested_exit_on_nmi(svm))
1584 return 0;
1585 nested_svm_simple_vmexit(svm, SVM_EXIT_NMI);
1586 return 0;
1587 }
1588
1589 if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
1590 if (block_nested_events)
1591 return -EBUSY;
1592 if (!nested_exit_on_intr(svm))
1593 return 0;
1594 trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
1595 nested_svm_simple_vmexit(svm, SVM_EXIT_INTR);
1596 return 0;
1597 }
1598
1599 return 0;
1600 }
1601
nested_svm_exit_special(struct vcpu_svm * svm)1602 int nested_svm_exit_special(struct vcpu_svm *svm)
1603 {
1604 u32 exit_code = svm->vmcb->control.exit_code;
1605 struct kvm_vcpu *vcpu = &svm->vcpu;
1606
1607 switch (exit_code) {
1608 case SVM_EXIT_INTR:
1609 case SVM_EXIT_NMI:
1610 case SVM_EXIT_NPF:
1611 return NESTED_EXIT_HOST;
1612 case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1613 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
1614
1615 if (svm->vmcb01.ptr->control.intercepts[INTERCEPT_EXCEPTION] &
1616 excp_bits)
1617 return NESTED_EXIT_HOST;
1618 else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR &&
1619 svm->vcpu.arch.apf.host_apf_flags)
1620 /* Trap async PF even if not shadowing */
1621 return NESTED_EXIT_HOST;
1622 break;
1623 }
1624 case SVM_EXIT_VMMCALL:
1625 /* Hyper-V L2 TLB flush hypercall is handled by L0 */
1626 if (guest_hv_cpuid_has_l2_tlb_flush(vcpu) &&
1627 nested_svm_l2_tlb_flush_enabled(vcpu) &&
1628 kvm_hv_is_tlb_flush_hcall(vcpu))
1629 return NESTED_EXIT_HOST;
1630 break;
1631 default:
1632 break;
1633 }
1634
1635 return NESTED_EXIT_CONTINUE;
1636 }
1637
nested_svm_update_tsc_ratio_msr(struct kvm_vcpu * vcpu)1638 void nested_svm_update_tsc_ratio_msr(struct kvm_vcpu *vcpu)
1639 {
1640 struct vcpu_svm *svm = to_svm(vcpu);
1641
1642 vcpu->arch.tsc_scaling_ratio =
1643 kvm_calc_nested_tsc_multiplier(vcpu->arch.l1_tsc_scaling_ratio,
1644 svm->tsc_ratio_msr);
1645 svm_write_tsc_multiplier(vcpu);
1646 }
1647
1648 /* Inverse operation of nested_copy_vmcb_control_to_cache(). asid is copied too. */
nested_copy_vmcb_cache_to_control(struct vmcb_control_area * dst,struct vmcb_ctrl_area_cached * from)1649 static void nested_copy_vmcb_cache_to_control(struct vmcb_control_area *dst,
1650 struct vmcb_ctrl_area_cached *from)
1651 {
1652 unsigned int i;
1653
1654 memset(dst, 0, sizeof(struct vmcb_control_area));
1655
1656 for (i = 0; i < MAX_INTERCEPT; i++)
1657 dst->intercepts[i] = from->intercepts[i];
1658
1659 dst->iopm_base_pa = from->iopm_base_pa;
1660 dst->msrpm_base_pa = from->msrpm_base_pa;
1661 dst->tsc_offset = from->tsc_offset;
1662 dst->asid = from->asid;
1663 dst->tlb_ctl = from->tlb_ctl;
1664 dst->int_ctl = from->int_ctl;
1665 dst->int_vector = from->int_vector;
1666 dst->int_state = from->int_state;
1667 dst->exit_code = from->exit_code;
1668 dst->exit_code_hi = from->exit_code_hi;
1669 dst->exit_info_1 = from->exit_info_1;
1670 dst->exit_info_2 = from->exit_info_2;
1671 dst->exit_int_info = from->exit_int_info;
1672 dst->exit_int_info_err = from->exit_int_info_err;
1673 dst->nested_ctl = from->nested_ctl;
1674 dst->event_inj = from->event_inj;
1675 dst->event_inj_err = from->event_inj_err;
1676 dst->next_rip = from->next_rip;
1677 dst->nested_cr3 = from->nested_cr3;
1678 dst->virt_ext = from->virt_ext;
1679 dst->pause_filter_count = from->pause_filter_count;
1680 dst->pause_filter_thresh = from->pause_filter_thresh;
1681 /* 'clean' and 'hv_enlightenments' are not changed by KVM */
1682 }
1683
svm_get_nested_state(struct kvm_vcpu * vcpu,struct kvm_nested_state __user * user_kvm_nested_state,u32 user_data_size)1684 static int svm_get_nested_state(struct kvm_vcpu *vcpu,
1685 struct kvm_nested_state __user *user_kvm_nested_state,
1686 u32 user_data_size)
1687 {
1688 struct vcpu_svm *svm;
1689 struct vmcb_control_area *ctl;
1690 unsigned long r;
1691 struct kvm_nested_state kvm_state = {
1692 .flags = 0,
1693 .format = KVM_STATE_NESTED_FORMAT_SVM,
1694 .size = sizeof(kvm_state),
1695 };
1696 struct vmcb __user *user_vmcb = (struct vmcb __user *)
1697 &user_kvm_nested_state->data.svm[0];
1698
1699 if (!vcpu)
1700 return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE;
1701
1702 svm = to_svm(vcpu);
1703
1704 if (user_data_size < kvm_state.size)
1705 goto out;
1706
1707 /* First fill in the header and copy it out. */
1708 if (is_guest_mode(vcpu)) {
1709 kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa;
1710 kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
1711 kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
1712
1713 if (svm->nested.nested_run_pending)
1714 kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING;
1715 }
1716
1717 if (gif_set(svm))
1718 kvm_state.flags |= KVM_STATE_NESTED_GIF_SET;
1719
1720 if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state)))
1721 return -EFAULT;
1722
1723 if (!is_guest_mode(vcpu))
1724 goto out;
1725
1726 /*
1727 * Copy over the full size of the VMCB rather than just the size
1728 * of the structs.
1729 */
1730 if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
1731 return -EFAULT;
1732
1733 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
1734 if (!ctl)
1735 return -ENOMEM;
1736
1737 nested_copy_vmcb_cache_to_control(ctl, &svm->nested.ctl);
1738 r = copy_to_user(&user_vmcb->control, ctl,
1739 sizeof(user_vmcb->control));
1740 kfree(ctl);
1741 if (r)
1742 return -EFAULT;
1743
1744 if (copy_to_user(&user_vmcb->save, &svm->vmcb01.ptr->save,
1745 sizeof(user_vmcb->save)))
1746 return -EFAULT;
1747 out:
1748 return kvm_state.size;
1749 }
1750
svm_set_nested_state(struct kvm_vcpu * vcpu,struct kvm_nested_state __user * user_kvm_nested_state,struct kvm_nested_state * kvm_state)1751 static int svm_set_nested_state(struct kvm_vcpu *vcpu,
1752 struct kvm_nested_state __user *user_kvm_nested_state,
1753 struct kvm_nested_state *kvm_state)
1754 {
1755 struct vcpu_svm *svm = to_svm(vcpu);
1756 struct vmcb __user *user_vmcb = (struct vmcb __user *)
1757 &user_kvm_nested_state->data.svm[0];
1758 struct vmcb_control_area *ctl;
1759 struct vmcb_save_area *save;
1760 struct vmcb_save_area_cached save_cached;
1761 struct vmcb_ctrl_area_cached ctl_cached;
1762 unsigned long cr0;
1763 int ret;
1764
1765 BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
1766 KVM_STATE_NESTED_SVM_VMCB_SIZE);
1767
1768 if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
1769 return -EINVAL;
1770
1771 if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE |
1772 KVM_STATE_NESTED_RUN_PENDING |
1773 KVM_STATE_NESTED_GIF_SET))
1774 return -EINVAL;
1775
1776 /*
1777 * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's
1778 * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed.
1779 */
1780 if (!(vcpu->arch.efer & EFER_SVME)) {
1781 /* GIF=1 and no guest mode are required if SVME=0. */
1782 if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET)
1783 return -EINVAL;
1784 }
1785
1786 /* SMM temporarily disables SVM, so we cannot be in guest mode. */
1787 if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE))
1788 return -EINVAL;
1789
1790 if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
1791 svm_leave_nested(vcpu);
1792 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1793 return 0;
1794 }
1795
1796 if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
1797 return -EINVAL;
1798 if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE)
1799 return -EINVAL;
1800
1801 ret = -ENOMEM;
1802 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
1803 save = kzalloc(sizeof(*save), GFP_KERNEL);
1804 if (!ctl || !save)
1805 goto out_free;
1806
1807 ret = -EFAULT;
1808 if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl)))
1809 goto out_free;
1810 if (copy_from_user(save, &user_vmcb->save, sizeof(*save)))
1811 goto out_free;
1812
1813 ret = -EINVAL;
1814 __nested_copy_vmcb_control_to_cache(vcpu, &ctl_cached, ctl);
1815 if (!__nested_vmcb_check_controls(vcpu, &ctl_cached))
1816 goto out_free;
1817
1818 /*
1819 * Processor state contains L2 state. Check that it is
1820 * valid for guest mode (see nested_vmcb_check_save).
1821 */
1822 cr0 = kvm_read_cr0(vcpu);
1823 if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
1824 goto out_free;
1825
1826 /*
1827 * Validate host state saved from before VMRUN (see
1828 * nested_svm_check_permissions).
1829 */
1830 __nested_copy_vmcb_save_to_cache(&save_cached, save);
1831 if (!(save->cr0 & X86_CR0_PG) ||
1832 !(save->cr0 & X86_CR0_PE) ||
1833 (save->rflags & X86_EFLAGS_VM) ||
1834 !__nested_vmcb_check_save(vcpu, &save_cached))
1835 goto out_free;
1836
1837
1838 /*
1839 * All checks done, we can enter guest mode. Userspace provides
1840 * vmcb12.control, which will be combined with L1 and stored into
1841 * vmcb02, and the L1 save state which we store in vmcb01.
1842 * L2 registers if needed are moved from the current VMCB to VMCB02.
1843 */
1844
1845 if (is_guest_mode(vcpu))
1846 svm_leave_nested(vcpu);
1847 else
1848 svm->nested.vmcb02.ptr->save = svm->vmcb01.ptr->save;
1849
1850 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1851
1852 svm->nested.nested_run_pending =
1853 !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);
1854
1855 svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;
1856
1857 svm_copy_vmrun_state(&svm->vmcb01.ptr->save, save);
1858 nested_copy_vmcb_control_to_cache(svm, ctl);
1859
1860 svm_switch_vmcb(svm, &svm->nested.vmcb02);
1861 nested_vmcb02_prepare_control(svm, svm->vmcb->save.rip, svm->vmcb->save.cs.base);
1862
1863 /*
1864 * While the nested guest CR3 is already checked and set by
1865 * KVM_SET_SREGS, it was set when nested state was yet loaded,
1866 * thus MMU might not be initialized correctly.
1867 * Set it again to fix this.
1868 */
1869
1870 ret = nested_svm_load_cr3(&svm->vcpu, vcpu->arch.cr3,
1871 nested_npt_enabled(svm), false);
1872 if (WARN_ON_ONCE(ret))
1873 goto out_free;
1874
1875 svm->nested.force_msr_bitmap_recalc = true;
1876
1877 kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1878 ret = 0;
1879 out_free:
1880 kfree(save);
1881 kfree(ctl);
1882
1883 return ret;
1884 }
1885
svm_get_nested_state_pages(struct kvm_vcpu * vcpu)1886 static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
1887 {
1888 if (WARN_ON(!is_guest_mode(vcpu)))
1889 return true;
1890
1891 if (!vcpu->arch.pdptrs_from_userspace &&
1892 !nested_npt_enabled(to_svm(vcpu)) && is_pae_paging(vcpu))
1893 /*
1894 * Reload the guest's PDPTRs since after a migration
1895 * the guest CR3 might be restored prior to setting the nested
1896 * state which can lead to a load of wrong PDPTRs.
1897 */
1898 if (CC(!load_pdptrs(vcpu, vcpu->arch.cr3)))
1899 return false;
1900
1901 if (!nested_svm_merge_msrpm(vcpu)) {
1902 vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1903 vcpu->run->internal.suberror =
1904 KVM_INTERNAL_ERROR_EMULATION;
1905 vcpu->run->internal.ndata = 0;
1906 return false;
1907 }
1908
1909 if (kvm_hv_verify_vp_assist(vcpu))
1910 return false;
1911
1912 return true;
1913 }
1914
1915 struct kvm_x86_nested_ops svm_nested_ops = {
1916 .leave_nested = svm_leave_nested,
1917 .is_exception_vmexit = nested_svm_is_exception_vmexit,
1918 .check_events = svm_check_nested_events,
1919 .triple_fault = nested_svm_triple_fault,
1920 .get_nested_state_pages = svm_get_nested_state_pages,
1921 .get_state = svm_get_nested_state,
1922 .set_state = svm_set_nested_state,
1923 .hv_inject_synthetic_vmexit_post_tlb_flush = svm_hv_inject_synthetic_vmexit_post_tlb_flush,
1924 };
1925