xref: /linux/arch/x86/kvm/svm/nested.c (revision 63eb28bb1402891b1ad2be02a530f29a9dd7f1cd)
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