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) "SVM: " 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 "cpuid.h"
29 #include "lapic.h"
30 #include "svm.h"
31
32 #define CC KVM_NESTED_VMENTER_CONSISTENCY_CHECK
33
nested_svm_inject_npf_exit(struct kvm_vcpu * vcpu,struct x86_exception * fault)34 static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
35 struct x86_exception *fault)
36 {
37 struct vcpu_svm *svm = to_svm(vcpu);
38
39 if (svm->vmcb->control.exit_code != SVM_EXIT_NPF) {
40 /*
41 * TODO: track the cause of the nested page fault, and
42 * correctly fill in the high bits of exit_info_1.
43 */
44 svm->vmcb->control.exit_code = SVM_EXIT_NPF;
45 svm->vmcb->control.exit_code_hi = 0;
46 svm->vmcb->control.exit_info_1 = (1ULL << 32);
47 svm->vmcb->control.exit_info_2 = fault->address;
48 }
49
50 svm->vmcb->control.exit_info_1 &= ~0xffffffffULL;
51 svm->vmcb->control.exit_info_1 |= fault->error_code;
52
53 nested_svm_vmexit(svm);
54 }
55
svm_inject_page_fault_nested(struct kvm_vcpu * vcpu,struct x86_exception * fault)56 static void svm_inject_page_fault_nested(struct kvm_vcpu *vcpu, struct x86_exception *fault)
57 {
58 struct vcpu_svm *svm = to_svm(vcpu);
59 WARN_ON(!is_guest_mode(vcpu));
60
61 if (vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_EXCEPTION_OFFSET + PF_VECTOR) &&
62 !svm->nested.nested_run_pending) {
63 svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + PF_VECTOR;
64 svm->vmcb->control.exit_code_hi = 0;
65 svm->vmcb->control.exit_info_1 = fault->error_code;
66 svm->vmcb->control.exit_info_2 = fault->address;
67 nested_svm_vmexit(svm);
68 } else {
69 kvm_inject_page_fault(vcpu, fault);
70 }
71 }
72
nested_svm_get_tdp_pdptr(struct kvm_vcpu * vcpu,int index)73 static u64 nested_svm_get_tdp_pdptr(struct kvm_vcpu *vcpu, int index)
74 {
75 struct vcpu_svm *svm = to_svm(vcpu);
76 u64 cr3 = svm->nested.ctl.nested_cr3;
77 u64 pdpte;
78 int ret;
79
80 ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(cr3), &pdpte,
81 offset_in_page(cr3) + index * 8, 8);
82 if (ret)
83 return 0;
84 return pdpte;
85 }
86
nested_svm_get_tdp_cr3(struct kvm_vcpu * vcpu)87 static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu)
88 {
89 struct vcpu_svm *svm = to_svm(vcpu);
90
91 return svm->nested.ctl.nested_cr3;
92 }
93
nested_svm_init_mmu_context(struct kvm_vcpu * vcpu)94 static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
95 {
96 struct vcpu_svm *svm = to_svm(vcpu);
97
98 WARN_ON(mmu_is_nested(vcpu));
99
100 vcpu->arch.mmu = &vcpu->arch.guest_mmu;
101
102 /*
103 * The NPT format depends on L1's CR4 and EFER, which is in vmcb01. Note,
104 * when called via KVM_SET_NESTED_STATE, that state may _not_ match current
105 * vCPU state. CR0.WP is explicitly ignored, while CR0.PG is required.
106 */
107 kvm_init_shadow_npt_mmu(vcpu, X86_CR0_PG, svm->vmcb01.ptr->save.cr4,
108 svm->vmcb01.ptr->save.efer,
109 svm->nested.ctl.nested_cr3);
110 vcpu->arch.mmu->get_guest_pgd = nested_svm_get_tdp_cr3;
111 vcpu->arch.mmu->get_pdptr = nested_svm_get_tdp_pdptr;
112 vcpu->arch.mmu->inject_page_fault = nested_svm_inject_npf_exit;
113 vcpu->arch.walk_mmu = &vcpu->arch.nested_mmu;
114 }
115
nested_svm_uninit_mmu_context(struct kvm_vcpu * vcpu)116 static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)
117 {
118 vcpu->arch.mmu = &vcpu->arch.root_mmu;
119 vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;
120 }
121
recalc_intercepts(struct vcpu_svm * svm)122 void recalc_intercepts(struct vcpu_svm *svm)
123 {
124 struct vmcb_control_area *c, *h, *g;
125 unsigned int i;
126
127 vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
128
129 if (!is_guest_mode(&svm->vcpu))
130 return;
131
132 c = &svm->vmcb->control;
133 h = &svm->vmcb01.ptr->control;
134 g = &svm->nested.ctl;
135
136 for (i = 0; i < MAX_INTERCEPT; i++)
137 c->intercepts[i] = h->intercepts[i];
138
139 if (g->int_ctl & V_INTR_MASKING_MASK) {
140 /* We only want the cr8 intercept bits of L1 */
141 vmcb_clr_intercept(c, INTERCEPT_CR8_READ);
142 vmcb_clr_intercept(c, INTERCEPT_CR8_WRITE);
143
144 /*
145 * Once running L2 with HF_VINTR_MASK, EFLAGS.IF does not
146 * affect any interrupt we may want to inject; therefore,
147 * interrupt window vmexits are irrelevant to L0.
148 */
149 vmcb_clr_intercept(c, INTERCEPT_VINTR);
150 }
151
152 /* We don't want to see VMMCALLs from a nested guest */
153 vmcb_clr_intercept(c, INTERCEPT_VMMCALL);
154
155 for (i = 0; i < MAX_INTERCEPT; i++)
156 c->intercepts[i] |= g->intercepts[i];
157
158 /* If SMI is not intercepted, ignore guest SMI intercept as well */
159 if (!intercept_smi)
160 vmcb_clr_intercept(c, INTERCEPT_SMI);
161
162 vmcb_set_intercept(c, INTERCEPT_VMLOAD);
163 vmcb_set_intercept(c, INTERCEPT_VMSAVE);
164 }
165
copy_vmcb_control_area(struct vmcb_control_area * dst,struct vmcb_control_area * from)166 static void copy_vmcb_control_area(struct vmcb_control_area *dst,
167 struct vmcb_control_area *from)
168 {
169 unsigned int i;
170
171 for (i = 0; i < MAX_INTERCEPT; i++)
172 dst->intercepts[i] = from->intercepts[i];
173
174 dst->iopm_base_pa = from->iopm_base_pa;
175 dst->msrpm_base_pa = from->msrpm_base_pa;
176 dst->tsc_offset = from->tsc_offset;
177 /* asid not copied, it is handled manually for svm->vmcb. */
178 dst->tlb_ctl = from->tlb_ctl;
179 dst->int_ctl = from->int_ctl;
180 dst->int_vector = from->int_vector;
181 dst->int_state = from->int_state;
182 dst->exit_code = from->exit_code;
183 dst->exit_code_hi = from->exit_code_hi;
184 dst->exit_info_1 = from->exit_info_1;
185 dst->exit_info_2 = from->exit_info_2;
186 dst->exit_int_info = from->exit_int_info;
187 dst->exit_int_info_err = from->exit_int_info_err;
188 dst->nested_ctl = from->nested_ctl;
189 dst->event_inj = from->event_inj;
190 dst->event_inj_err = from->event_inj_err;
191 dst->nested_cr3 = from->nested_cr3;
192 dst->virt_ext = from->virt_ext;
193 dst->pause_filter_count = from->pause_filter_count;
194 dst->pause_filter_thresh = from->pause_filter_thresh;
195 }
196
nested_svm_vmrun_msrpm(struct vcpu_svm * svm)197 static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
198 {
199 /*
200 * This function merges the msr permission bitmaps of kvm and the
201 * nested vmcb. It is optimized in that it only merges the parts where
202 * the kvm msr permission bitmap may contain zero bits
203 */
204 int i;
205
206 if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
207 return true;
208
209 for (i = 0; i < MSRPM_OFFSETS; i++) {
210 u32 value, p;
211 u64 offset;
212
213 if (msrpm_offsets[i] == 0xffffffff)
214 break;
215
216 p = msrpm_offsets[i];
217 offset = svm->nested.ctl.msrpm_base_pa + (p * 4);
218
219 if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4))
220 return false;
221
222 svm->nested.msrpm[p] = svm->msrpm[p] | value;
223 }
224
225 svm->vmcb->control.msrpm_base_pa = __sme_set(__pa(svm->nested.msrpm));
226
227 return true;
228 }
229
230 /*
231 * Bits 11:0 of bitmap address are ignored by hardware
232 */
nested_svm_check_bitmap_pa(struct kvm_vcpu * vcpu,u64 pa,u32 size)233 static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size)
234 {
235 u64 addr = PAGE_ALIGN(pa);
236
237 return kvm_vcpu_is_legal_gpa(vcpu, addr) &&
238 kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1);
239 }
240
nested_svm_check_tlb_ctl(struct kvm_vcpu * vcpu,u8 tlb_ctl)241 static bool nested_svm_check_tlb_ctl(struct kvm_vcpu *vcpu, u8 tlb_ctl)
242 {
243 /* Nested FLUSHBYASID is not supported yet. */
244 switch(tlb_ctl) {
245 case TLB_CONTROL_DO_NOTHING:
246 case TLB_CONTROL_FLUSH_ALL_ASID:
247 return true;
248 default:
249 return false;
250 }
251 }
252
nested_vmcb_check_controls(struct kvm_vcpu * vcpu,struct vmcb_control_area * control)253 static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu,
254 struct vmcb_control_area *control)
255 {
256 if (CC(!vmcb_is_intercept(control, INTERCEPT_VMRUN)))
257 return false;
258
259 if (CC(control->asid == 0))
260 return false;
261
262 if (CC((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && !npt_enabled))
263 return false;
264
265 if (CC(!nested_svm_check_bitmap_pa(vcpu, control->msrpm_base_pa,
266 MSRPM_SIZE)))
267 return false;
268 if (CC(!nested_svm_check_bitmap_pa(vcpu, control->iopm_base_pa,
269 IOPM_SIZE)))
270 return false;
271
272 if (CC(!nested_svm_check_tlb_ctl(vcpu, control->tlb_ctl)))
273 return false;
274
275 return true;
276 }
277
nested_vmcb_check_cr3_cr4(struct kvm_vcpu * vcpu,struct vmcb_save_area * save)278 static bool nested_vmcb_check_cr3_cr4(struct kvm_vcpu *vcpu,
279 struct vmcb_save_area *save)
280 {
281 /*
282 * These checks are also performed by KVM_SET_SREGS,
283 * except that EFER.LMA is not checked by SVM against
284 * CR0.PG && EFER.LME.
285 */
286 if ((save->efer & EFER_LME) && (save->cr0 & X86_CR0_PG)) {
287 if (CC(!(save->cr4 & X86_CR4_PAE)) ||
288 CC(!(save->cr0 & X86_CR0_PE)) ||
289 CC(kvm_vcpu_is_illegal_gpa(vcpu, save->cr3)))
290 return false;
291 }
292
293 if (CC(!kvm_is_valid_cr4(vcpu, save->cr4)))
294 return false;
295
296 return true;
297 }
298
299 /* Common checks that apply to both L1 and L2 state. */
nested_vmcb_valid_sregs(struct kvm_vcpu * vcpu,struct vmcb_save_area * save)300 static bool nested_vmcb_valid_sregs(struct kvm_vcpu *vcpu,
301 struct vmcb_save_area *save)
302 {
303 /*
304 * FIXME: these should be done after copying the fields,
305 * to avoid TOC/TOU races. For these save area checks
306 * the possible damage is limited since kvm_set_cr0 and
307 * kvm_set_cr4 handle failure; EFER_SVME is an exception
308 * so it is force-set later in nested_prepare_vmcb_save.
309 */
310 if (CC(!(save->efer & EFER_SVME)))
311 return false;
312
313 if (CC((save->cr0 & X86_CR0_CD) == 0 && (save->cr0 & X86_CR0_NW)) ||
314 CC(save->cr0 & ~0xffffffffULL))
315 return false;
316
317 if (CC(!kvm_dr6_valid(save->dr6)) || CC(!kvm_dr7_valid(save->dr7)))
318 return false;
319
320 if (!nested_vmcb_check_cr3_cr4(vcpu, save))
321 return false;
322
323 if (CC(!kvm_valid_efer(vcpu, save->efer)))
324 return false;
325
326 return true;
327 }
328
nested_load_control_from_vmcb12(struct vcpu_svm * svm,struct vmcb_control_area * control)329 void nested_load_control_from_vmcb12(struct vcpu_svm *svm,
330 struct vmcb_control_area *control)
331 {
332 copy_vmcb_control_area(&svm->nested.ctl, control);
333
334 /* Copy it here because nested_svm_check_controls will check it. */
335 svm->nested.ctl.asid = control->asid;
336 svm->nested.ctl.msrpm_base_pa &= ~0x0fffULL;
337 svm->nested.ctl.iopm_base_pa &= ~0x0fffULL;
338 }
339
340 /*
341 * Synchronize fields that are written by the processor, so that
342 * they can be copied back into the vmcb12.
343 */
nested_sync_control_from_vmcb02(struct vcpu_svm * svm)344 void nested_sync_control_from_vmcb02(struct vcpu_svm *svm)
345 {
346 u32 mask;
347 svm->nested.ctl.event_inj = svm->vmcb->control.event_inj;
348 svm->nested.ctl.event_inj_err = svm->vmcb->control.event_inj_err;
349
350 /* Only a few fields of int_ctl are written by the processor. */
351 mask = V_IRQ_MASK | V_TPR_MASK;
352 if (!(svm->nested.ctl.int_ctl & V_INTR_MASKING_MASK) &&
353 svm_is_intercept(svm, INTERCEPT_VINTR)) {
354 /*
355 * In order to request an interrupt window, L0 is usurping
356 * svm->vmcb->control.int_ctl and possibly setting V_IRQ
357 * even if it was clear in L1's VMCB. Restoring it would be
358 * wrong. However, in this case V_IRQ will remain true until
359 * interrupt_window_interception calls svm_clear_vintr and
360 * restores int_ctl. We can just leave it aside.
361 */
362 mask &= ~V_IRQ_MASK;
363 }
364 svm->nested.ctl.int_ctl &= ~mask;
365 svm->nested.ctl.int_ctl |= svm->vmcb->control.int_ctl & mask;
366 }
367
368 /*
369 * Transfer any event that L0 or L1 wanted to inject into L2 to
370 * EXIT_INT_INFO.
371 */
nested_save_pending_event_to_vmcb12(struct vcpu_svm * svm,struct vmcb * vmcb12)372 static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm,
373 struct vmcb *vmcb12)
374 {
375 struct kvm_vcpu *vcpu = &svm->vcpu;
376 u32 exit_int_info = 0;
377 unsigned int nr;
378
379 if (vcpu->arch.exception.injected) {
380 nr = vcpu->arch.exception.nr;
381 exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT;
382
383 if (vcpu->arch.exception.has_error_code) {
384 exit_int_info |= SVM_EVTINJ_VALID_ERR;
385 vmcb12->control.exit_int_info_err =
386 vcpu->arch.exception.error_code;
387 }
388
389 } else if (vcpu->arch.nmi_injected) {
390 exit_int_info = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI;
391
392 } else if (vcpu->arch.interrupt.injected) {
393 nr = vcpu->arch.interrupt.nr;
394 exit_int_info = nr | SVM_EVTINJ_VALID;
395
396 if (vcpu->arch.interrupt.soft)
397 exit_int_info |= SVM_EVTINJ_TYPE_SOFT;
398 else
399 exit_int_info |= SVM_EVTINJ_TYPE_INTR;
400 }
401
402 vmcb12->control.exit_int_info = exit_int_info;
403 }
404
nested_npt_enabled(struct vcpu_svm * svm)405 static inline bool nested_npt_enabled(struct vcpu_svm *svm)
406 {
407 return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE;
408 }
409
nested_svm_transition_tlb_flush(struct kvm_vcpu * vcpu)410 static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu)
411 {
412 /*
413 * TODO: optimize unconditional TLB flush/MMU sync. A partial list of
414 * things to fix before this can be conditional:
415 *
416 * - Flush TLBs for both L1 and L2 remote TLB flush
417 * - Honor L1's request to flush an ASID on nested VMRUN
418 * - Sync nested NPT MMU on VMRUN that flushes L2's ASID[*]
419 * - Don't crush a pending TLB flush in vmcb02 on nested VMRUN
420 * - Flush L1's ASID on KVM_REQ_TLB_FLUSH_GUEST
421 *
422 * [*] Unlike nested EPT, SVM's ASID management can invalidate nested
423 * NPT guest-physical mappings on VMRUN.
424 */
425 kvm_make_request(KVM_REQ_MMU_SYNC, vcpu);
426 kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
427 }
428
429 /*
430 * Load guest's/host's cr3 on nested vmentry or vmexit. @nested_npt is true
431 * if we are emulating VM-Entry into a guest with NPT enabled.
432 */
nested_svm_load_cr3(struct kvm_vcpu * vcpu,unsigned long cr3,bool nested_npt,bool reload_pdptrs)433 static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
434 bool nested_npt, bool reload_pdptrs)
435 {
436 if (CC(kvm_vcpu_is_illegal_gpa(vcpu, cr3)))
437 return -EINVAL;
438
439 if (reload_pdptrs && !nested_npt && is_pae_paging(vcpu) &&
440 CC(!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)))
441 return -EINVAL;
442
443 if (!nested_npt)
444 kvm_mmu_new_pgd(vcpu, cr3);
445
446 vcpu->arch.cr3 = cr3;
447 kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
448
449 /* Re-initialize the MMU, e.g. to pick up CR4 MMU role changes. */
450 kvm_init_mmu(vcpu);
451
452 return 0;
453 }
454
nested_vmcb02_compute_g_pat(struct vcpu_svm * svm)455 void nested_vmcb02_compute_g_pat(struct vcpu_svm *svm)
456 {
457 if (!svm->nested.vmcb02.ptr)
458 return;
459
460 /* FIXME: merge g_pat from vmcb01 and vmcb12. */
461 svm->nested.vmcb02.ptr->save.g_pat = svm->vmcb01.ptr->save.g_pat;
462 }
463
nested_vmcb02_prepare_save(struct vcpu_svm * svm,struct vmcb * vmcb12)464 static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12)
465 {
466 bool new_vmcb12 = false;
467
468 nested_vmcb02_compute_g_pat(svm);
469
470 /* Load the nested guest state */
471 if (svm->nested.vmcb12_gpa != svm->nested.last_vmcb12_gpa) {
472 new_vmcb12 = true;
473 svm->nested.last_vmcb12_gpa = svm->nested.vmcb12_gpa;
474 }
475
476 if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_SEG))) {
477 svm->vmcb->save.es = vmcb12->save.es;
478 svm->vmcb->save.cs = vmcb12->save.cs;
479 svm->vmcb->save.ss = vmcb12->save.ss;
480 svm->vmcb->save.ds = vmcb12->save.ds;
481 svm->vmcb->save.cpl = vmcb12->save.cpl;
482 vmcb_mark_dirty(svm->vmcb, VMCB_SEG);
483 }
484
485 if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DT))) {
486 svm->vmcb->save.gdtr = vmcb12->save.gdtr;
487 svm->vmcb->save.idtr = vmcb12->save.idtr;
488 vmcb_mark_dirty(svm->vmcb, VMCB_DT);
489 }
490
491 kvm_set_rflags(&svm->vcpu, vmcb12->save.rflags | X86_EFLAGS_FIXED);
492
493 /*
494 * Force-set EFER_SVME even though it is checked earlier on the
495 * VMCB12, because the guest can flip the bit between the check
496 * and now. Clearing EFER_SVME would call svm_free_nested.
497 */
498 svm_set_efer(&svm->vcpu, vmcb12->save.efer | EFER_SVME);
499
500 svm_set_cr0(&svm->vcpu, vmcb12->save.cr0);
501 svm_set_cr4(&svm->vcpu, vmcb12->save.cr4);
502
503 svm->vcpu.arch.cr2 = vmcb12->save.cr2;
504
505 kvm_rax_write(&svm->vcpu, vmcb12->save.rax);
506 kvm_rsp_write(&svm->vcpu, vmcb12->save.rsp);
507 kvm_rip_write(&svm->vcpu, vmcb12->save.rip);
508
509 /* In case we don't even reach vcpu_run, the fields are not updated */
510 svm->vmcb->save.rax = vmcb12->save.rax;
511 svm->vmcb->save.rsp = vmcb12->save.rsp;
512 svm->vmcb->save.rip = vmcb12->save.rip;
513
514 /* These bits will be set properly on the first execution when new_vmc12 is true */
515 if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_DR))) {
516 svm->vmcb->save.dr7 = vmcb12->save.dr7 | DR7_FIXED_1;
517 svm->vcpu.arch.dr6 = vmcb12->save.dr6 | DR6_ACTIVE_LOW;
518 vmcb_mark_dirty(svm->vmcb, VMCB_DR);
519 }
520 }
521
nested_vmcb02_prepare_control(struct vcpu_svm * svm)522 static void nested_vmcb02_prepare_control(struct vcpu_svm *svm)
523 {
524 const u32 int_ctl_vmcb01_bits =
525 V_INTR_MASKING_MASK | V_GIF_MASK | V_GIF_ENABLE_MASK;
526
527 const u32 int_ctl_vmcb12_bits = V_TPR_MASK | V_IRQ_INJECTION_BITS_MASK;
528
529 struct kvm_vcpu *vcpu = &svm->vcpu;
530
531 /*
532 * Filled at exit: exit_code, exit_code_hi, exit_info_1, exit_info_2,
533 * exit_int_info, exit_int_info_err, next_rip, insn_len, insn_bytes.
534 */
535
536 /*
537 * Also covers avic_vapic_bar, avic_backing_page, avic_logical_id,
538 * avic_physical_id.
539 */
540 WARN_ON(kvm_apicv_activated(svm->vcpu.kvm));
541
542 /* Copied from vmcb01. msrpm_base can be overwritten later. */
543 svm->vmcb->control.nested_ctl = svm->vmcb01.ptr->control.nested_ctl;
544 svm->vmcb->control.iopm_base_pa = svm->vmcb01.ptr->control.iopm_base_pa;
545 svm->vmcb->control.msrpm_base_pa = svm->vmcb01.ptr->control.msrpm_base_pa;
546
547 /* Done at vmrun: asid. */
548
549 /* Also overwritten later if necessary. */
550 svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
551
552 /* nested_cr3. */
553 if (nested_npt_enabled(svm))
554 nested_svm_init_mmu_context(vcpu);
555
556 vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset(
557 vcpu->arch.l1_tsc_offset,
558 svm->nested.ctl.tsc_offset,
559 svm->tsc_ratio_msr);
560
561 svm->vmcb->control.tsc_offset = vcpu->arch.tsc_offset;
562
563 if (svm->tsc_ratio_msr != kvm_default_tsc_scaling_ratio) {
564 WARN_ON(!svm->tsc_scaling_enabled);
565 nested_svm_update_tsc_ratio_msr(vcpu);
566 }
567
568 svm->vmcb->control.int_ctl =
569 (svm->nested.ctl.int_ctl & int_ctl_vmcb12_bits) |
570 (svm->vmcb01.ptr->control.int_ctl & int_ctl_vmcb01_bits);
571
572 svm->vmcb->control.int_vector = svm->nested.ctl.int_vector;
573 svm->vmcb->control.int_state = svm->nested.ctl.int_state;
574 svm->vmcb->control.event_inj = svm->nested.ctl.event_inj;
575 svm->vmcb->control.event_inj_err = svm->nested.ctl.event_inj_err;
576
577 nested_svm_transition_tlb_flush(vcpu);
578
579 /* Enter Guest-Mode */
580 enter_guest_mode(vcpu);
581
582 /*
583 * Merge guest and host intercepts - must be called with vcpu in
584 * guest-mode to take effect.
585 */
586 recalc_intercepts(svm);
587 }
588
nested_svm_copy_common_state(struct vmcb * from_vmcb,struct vmcb * to_vmcb)589 static void nested_svm_copy_common_state(struct vmcb *from_vmcb, struct vmcb *to_vmcb)
590 {
591 /*
592 * Some VMCB state is shared between L1 and L2 and thus has to be
593 * moved at the time of nested vmrun and vmexit.
594 *
595 * VMLOAD/VMSAVE state would also belong in this category, but KVM
596 * always performs VMLOAD and VMSAVE from the VMCB01.
597 */
598 to_vmcb->save.spec_ctrl = from_vmcb->save.spec_ctrl;
599 }
600
enter_svm_guest_mode(struct kvm_vcpu * vcpu,u64 vmcb12_gpa,struct vmcb * vmcb12,bool from_vmrun)601 int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa,
602 struct vmcb *vmcb12, bool from_vmrun)
603 {
604 struct vcpu_svm *svm = to_svm(vcpu);
605 int ret;
606
607 trace_kvm_nested_vmrun(svm->vmcb->save.rip, vmcb12_gpa,
608 vmcb12->save.rip,
609 vmcb12->control.int_ctl,
610 vmcb12->control.event_inj,
611 vmcb12->control.nested_ctl);
612
613 trace_kvm_nested_intercepts(vmcb12->control.intercepts[INTERCEPT_CR] & 0xffff,
614 vmcb12->control.intercepts[INTERCEPT_CR] >> 16,
615 vmcb12->control.intercepts[INTERCEPT_EXCEPTION],
616 vmcb12->control.intercepts[INTERCEPT_WORD3],
617 vmcb12->control.intercepts[INTERCEPT_WORD4],
618 vmcb12->control.intercepts[INTERCEPT_WORD5]);
619
620
621 svm->nested.vmcb12_gpa = vmcb12_gpa;
622
623 WARN_ON(svm->vmcb == svm->nested.vmcb02.ptr);
624
625 nested_svm_copy_common_state(svm->vmcb01.ptr, svm->nested.vmcb02.ptr);
626
627 svm_switch_vmcb(svm, &svm->nested.vmcb02);
628 nested_vmcb02_prepare_control(svm);
629 nested_vmcb02_prepare_save(svm, vmcb12);
630
631 ret = nested_svm_load_cr3(&svm->vcpu, vmcb12->save.cr3,
632 nested_npt_enabled(svm), from_vmrun);
633 if (ret)
634 return ret;
635
636 if (!npt_enabled)
637 vcpu->arch.mmu->inject_page_fault = svm_inject_page_fault_nested;
638
639 if (!from_vmrun)
640 kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
641
642 svm_set_gif(svm, true);
643
644 return 0;
645 }
646
nested_svm_vmrun(struct kvm_vcpu * vcpu)647 int nested_svm_vmrun(struct kvm_vcpu *vcpu)
648 {
649 struct vcpu_svm *svm = to_svm(vcpu);
650 int ret;
651 struct vmcb *vmcb12;
652 struct kvm_host_map map;
653 u64 vmcb12_gpa;
654
655 if (!svm->nested.hsave_msr) {
656 kvm_inject_gp(vcpu, 0);
657 return 1;
658 }
659
660 if (is_smm(vcpu)) {
661 kvm_queue_exception(vcpu, UD_VECTOR);
662 return 1;
663 }
664
665 vmcb12_gpa = svm->vmcb->save.rax;
666 ret = kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map);
667 if (ret == -EINVAL) {
668 kvm_inject_gp(vcpu, 0);
669 return 1;
670 } else if (ret) {
671 return kvm_skip_emulated_instruction(vcpu);
672 }
673
674 ret = kvm_skip_emulated_instruction(vcpu);
675
676 vmcb12 = map.hva;
677
678 if (WARN_ON_ONCE(!svm->nested.initialized))
679 return -EINVAL;
680
681 nested_load_control_from_vmcb12(svm, &vmcb12->control);
682
683 if (!nested_vmcb_valid_sregs(vcpu, &vmcb12->save) ||
684 !nested_vmcb_check_controls(vcpu, &svm->nested.ctl)) {
685 vmcb12->control.exit_code = SVM_EXIT_ERR;
686 vmcb12->control.exit_code_hi = 0;
687 vmcb12->control.exit_info_1 = 0;
688 vmcb12->control.exit_info_2 = 0;
689 goto out;
690 }
691
692 /*
693 * Since vmcb01 is not in use, we can use it to store some of the L1
694 * state.
695 */
696 svm->vmcb01.ptr->save.efer = vcpu->arch.efer;
697 svm->vmcb01.ptr->save.cr0 = kvm_read_cr0(vcpu);
698 svm->vmcb01.ptr->save.cr4 = vcpu->arch.cr4;
699 svm->vmcb01.ptr->save.rflags = kvm_get_rflags(vcpu);
700 svm->vmcb01.ptr->save.rip = kvm_rip_read(vcpu);
701
702 if (!npt_enabled)
703 svm->vmcb01.ptr->save.cr3 = kvm_read_cr3(vcpu);
704
705 svm->nested.nested_run_pending = 1;
706
707 if (enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12, true))
708 goto out_exit_err;
709
710 if (nested_svm_vmrun_msrpm(svm))
711 goto out;
712
713 out_exit_err:
714 svm->nested.nested_run_pending = 0;
715
716 svm->vmcb->control.exit_code = SVM_EXIT_ERR;
717 svm->vmcb->control.exit_code_hi = 0;
718 svm->vmcb->control.exit_info_1 = 0;
719 svm->vmcb->control.exit_info_2 = 0;
720
721 nested_svm_vmexit(svm);
722
723 out:
724 kvm_vcpu_unmap(vcpu, &map, true);
725
726 return ret;
727 }
728
729 /* 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)730 void svm_copy_vmrun_state(struct vmcb_save_area *to_save,
731 struct vmcb_save_area *from_save)
732 {
733 to_save->es = from_save->es;
734 to_save->cs = from_save->cs;
735 to_save->ss = from_save->ss;
736 to_save->ds = from_save->ds;
737 to_save->gdtr = from_save->gdtr;
738 to_save->idtr = from_save->idtr;
739 to_save->rflags = from_save->rflags | X86_EFLAGS_FIXED;
740 to_save->efer = from_save->efer;
741 to_save->cr0 = from_save->cr0;
742 to_save->cr3 = from_save->cr3;
743 to_save->cr4 = from_save->cr4;
744 to_save->rax = from_save->rax;
745 to_save->rsp = from_save->rsp;
746 to_save->rip = from_save->rip;
747 to_save->cpl = 0;
748 }
749
svm_copy_vmloadsave_state(struct vmcb * to_vmcb,struct vmcb * from_vmcb)750 void svm_copy_vmloadsave_state(struct vmcb *to_vmcb, struct vmcb *from_vmcb)
751 {
752 to_vmcb->save.fs = from_vmcb->save.fs;
753 to_vmcb->save.gs = from_vmcb->save.gs;
754 to_vmcb->save.tr = from_vmcb->save.tr;
755 to_vmcb->save.ldtr = from_vmcb->save.ldtr;
756 to_vmcb->save.kernel_gs_base = from_vmcb->save.kernel_gs_base;
757 to_vmcb->save.star = from_vmcb->save.star;
758 to_vmcb->save.lstar = from_vmcb->save.lstar;
759 to_vmcb->save.cstar = from_vmcb->save.cstar;
760 to_vmcb->save.sfmask = from_vmcb->save.sfmask;
761 to_vmcb->save.sysenter_cs = from_vmcb->save.sysenter_cs;
762 to_vmcb->save.sysenter_esp = from_vmcb->save.sysenter_esp;
763 to_vmcb->save.sysenter_eip = from_vmcb->save.sysenter_eip;
764 }
765
nested_svm_vmexit(struct vcpu_svm * svm)766 int nested_svm_vmexit(struct vcpu_svm *svm)
767 {
768 struct kvm_vcpu *vcpu = &svm->vcpu;
769 struct vmcb *vmcb12;
770 struct vmcb *vmcb = svm->vmcb;
771 struct kvm_host_map map;
772 int rc;
773
774 /* Triple faults in L2 should never escape. */
775 WARN_ON_ONCE(kvm_check_request(KVM_REQ_TRIPLE_FAULT, vcpu));
776
777 rc = kvm_vcpu_map(vcpu, gpa_to_gfn(svm->nested.vmcb12_gpa), &map);
778 if (rc) {
779 if (rc == -EINVAL)
780 kvm_inject_gp(vcpu, 0);
781 return 1;
782 }
783
784 vmcb12 = map.hva;
785
786 /* Exit Guest-Mode */
787 leave_guest_mode(vcpu);
788 svm->nested.vmcb12_gpa = 0;
789 WARN_ON_ONCE(svm->nested.nested_run_pending);
790
791 kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
792
793 /* in case we halted in L2 */
794 svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE;
795
796 /* Give the current vmcb to the guest */
797
798 vmcb12->save.es = vmcb->save.es;
799 vmcb12->save.cs = vmcb->save.cs;
800 vmcb12->save.ss = vmcb->save.ss;
801 vmcb12->save.ds = vmcb->save.ds;
802 vmcb12->save.gdtr = vmcb->save.gdtr;
803 vmcb12->save.idtr = vmcb->save.idtr;
804 vmcb12->save.efer = svm->vcpu.arch.efer;
805 vmcb12->save.cr0 = kvm_read_cr0(vcpu);
806 vmcb12->save.cr3 = kvm_read_cr3(vcpu);
807 vmcb12->save.cr2 = vmcb->save.cr2;
808 vmcb12->save.cr4 = svm->vcpu.arch.cr4;
809 vmcb12->save.rflags = kvm_get_rflags(vcpu);
810 vmcb12->save.rip = kvm_rip_read(vcpu);
811 vmcb12->save.rsp = kvm_rsp_read(vcpu);
812 vmcb12->save.rax = kvm_rax_read(vcpu);
813 vmcb12->save.dr7 = vmcb->save.dr7;
814 vmcb12->save.dr6 = svm->vcpu.arch.dr6;
815 vmcb12->save.cpl = vmcb->save.cpl;
816
817 vmcb12->control.int_state = vmcb->control.int_state;
818 vmcb12->control.exit_code = vmcb->control.exit_code;
819 vmcb12->control.exit_code_hi = vmcb->control.exit_code_hi;
820 vmcb12->control.exit_info_1 = vmcb->control.exit_info_1;
821 vmcb12->control.exit_info_2 = vmcb->control.exit_info_2;
822
823 if (vmcb12->control.exit_code != SVM_EXIT_ERR)
824 nested_save_pending_event_to_vmcb12(svm, vmcb12);
825
826 if (svm->nrips_enabled)
827 vmcb12->control.next_rip = vmcb->control.next_rip;
828
829 vmcb12->control.int_ctl = svm->nested.ctl.int_ctl;
830 vmcb12->control.tlb_ctl = svm->nested.ctl.tlb_ctl;
831 vmcb12->control.event_inj = svm->nested.ctl.event_inj;
832 vmcb12->control.event_inj_err = svm->nested.ctl.event_inj_err;
833
834 nested_svm_copy_common_state(svm->nested.vmcb02.ptr, svm->vmcb01.ptr);
835
836 svm_switch_vmcb(svm, &svm->vmcb01);
837
838 /*
839 * On vmexit the GIF is set to false and
840 * no event can be injected in L1.
841 */
842 svm_set_gif(svm, false);
843 svm->vmcb->control.exit_int_info = 0;
844
845 svm->vcpu.arch.tsc_offset = svm->vcpu.arch.l1_tsc_offset;
846 if (svm->vmcb->control.tsc_offset != svm->vcpu.arch.tsc_offset) {
847 svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset;
848 vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
849 }
850
851 if (svm->tsc_ratio_msr != kvm_default_tsc_scaling_ratio) {
852 WARN_ON(!svm->tsc_scaling_enabled);
853 vcpu->arch.tsc_scaling_ratio = vcpu->arch.l1_tsc_scaling_ratio;
854 svm_write_tsc_multiplier(vcpu, vcpu->arch.tsc_scaling_ratio);
855 }
856
857 svm->nested.ctl.nested_cr3 = 0;
858
859 /*
860 * Restore processor state that had been saved in vmcb01
861 */
862 kvm_set_rflags(vcpu, svm->vmcb->save.rflags);
863 svm_set_efer(vcpu, svm->vmcb->save.efer);
864 svm_set_cr0(vcpu, svm->vmcb->save.cr0 | X86_CR0_PE);
865 svm_set_cr4(vcpu, svm->vmcb->save.cr4);
866 kvm_rax_write(vcpu, svm->vmcb->save.rax);
867 kvm_rsp_write(vcpu, svm->vmcb->save.rsp);
868 kvm_rip_write(vcpu, svm->vmcb->save.rip);
869
870 svm->vcpu.arch.dr7 = DR7_FIXED_1;
871 kvm_update_dr7(&svm->vcpu);
872
873 trace_kvm_nested_vmexit_inject(vmcb12->control.exit_code,
874 vmcb12->control.exit_info_1,
875 vmcb12->control.exit_info_2,
876 vmcb12->control.exit_int_info,
877 vmcb12->control.exit_int_info_err,
878 KVM_ISA_SVM);
879
880 kvm_vcpu_unmap(vcpu, &map, true);
881
882 nested_svm_transition_tlb_flush(vcpu);
883
884 nested_svm_uninit_mmu_context(vcpu);
885
886 rc = nested_svm_load_cr3(vcpu, svm->vmcb->save.cr3, false, true);
887 if (rc)
888 return 1;
889
890 /*
891 * Drop what we picked up for L2 via svm_complete_interrupts() so it
892 * doesn't end up in L1.
893 */
894 svm->vcpu.arch.nmi_injected = false;
895 kvm_clear_exception_queue(vcpu);
896 kvm_clear_interrupt_queue(vcpu);
897
898 /*
899 * If we are here following the completion of a VMRUN that
900 * is being single-stepped, queue the pending #DB intercept
901 * right now so that it an be accounted for before we execute
902 * L1's next instruction.
903 */
904 if (unlikely(svm->vmcb->save.rflags & X86_EFLAGS_TF))
905 kvm_queue_exception(&(svm->vcpu), DB_VECTOR);
906
907 return 0;
908 }
909
nested_svm_triple_fault(struct kvm_vcpu * vcpu)910 static void nested_svm_triple_fault(struct kvm_vcpu *vcpu)
911 {
912 nested_svm_simple_vmexit(to_svm(vcpu), SVM_EXIT_SHUTDOWN);
913 }
914
svm_allocate_nested(struct vcpu_svm * svm)915 int svm_allocate_nested(struct vcpu_svm *svm)
916 {
917 struct page *vmcb02_page;
918
919 if (svm->nested.initialized)
920 return 0;
921
922 vmcb02_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
923 if (!vmcb02_page)
924 return -ENOMEM;
925 svm->nested.vmcb02.ptr = page_address(vmcb02_page);
926 svm->nested.vmcb02.pa = __sme_set(page_to_pfn(vmcb02_page) << PAGE_SHIFT);
927
928 svm->nested.msrpm = svm_vcpu_alloc_msrpm();
929 if (!svm->nested.msrpm)
930 goto err_free_vmcb02;
931 svm_vcpu_init_msrpm(&svm->vcpu, svm->nested.msrpm);
932
933 svm->nested.initialized = true;
934 return 0;
935
936 err_free_vmcb02:
937 __free_page(vmcb02_page);
938 return -ENOMEM;
939 }
940
svm_free_nested(struct vcpu_svm * svm)941 void svm_free_nested(struct vcpu_svm *svm)
942 {
943 if (!svm->nested.initialized)
944 return;
945
946 svm_vcpu_free_msrpm(svm->nested.msrpm);
947 svm->nested.msrpm = NULL;
948
949 __free_page(virt_to_page(svm->nested.vmcb02.ptr));
950 svm->nested.vmcb02.ptr = NULL;
951
952 /*
953 * When last_vmcb12_gpa matches the current vmcb12 gpa,
954 * some vmcb12 fields are not loaded if they are marked clean
955 * in the vmcb12, since in this case they are up to date already.
956 *
957 * When the vmcb02 is freed, this optimization becomes invalid.
958 */
959 svm->nested.last_vmcb12_gpa = INVALID_GPA;
960
961 svm->nested.initialized = false;
962 }
963
964 /*
965 * Forcibly leave nested mode in order to be able to reset the VCPU later on.
966 */
svm_leave_nested(struct vcpu_svm * svm)967 void svm_leave_nested(struct vcpu_svm *svm)
968 {
969 struct kvm_vcpu *vcpu = &svm->vcpu;
970
971 if (is_guest_mode(vcpu)) {
972 svm->nested.nested_run_pending = 0;
973 svm->nested.vmcb12_gpa = INVALID_GPA;
974
975 leave_guest_mode(vcpu);
976
977 svm_switch_vmcb(svm, &svm->vmcb01);
978
979 nested_svm_uninit_mmu_context(vcpu);
980 vmcb_mark_all_dirty(svm->vmcb);
981 }
982
983 kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
984 }
985
nested_svm_exit_handled_msr(struct vcpu_svm * svm)986 static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
987 {
988 u32 offset, msr, value;
989 int write, mask;
990
991 if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
992 return NESTED_EXIT_HOST;
993
994 msr = svm->vcpu.arch.regs[VCPU_REGS_RCX];
995 offset = svm_msrpm_offset(msr);
996 write = svm->vmcb->control.exit_info_1 & 1;
997 mask = 1 << ((2 * (msr & 0xf)) + write);
998
999 if (offset == MSR_INVALID)
1000 return NESTED_EXIT_DONE;
1001
1002 /* Offset is in 32 bit units but need in 8 bit units */
1003 offset *= 4;
1004
1005 if (kvm_vcpu_read_guest(&svm->vcpu, svm->nested.ctl.msrpm_base_pa + offset, &value, 4))
1006 return NESTED_EXIT_DONE;
1007
1008 return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
1009 }
1010
nested_svm_intercept_ioio(struct vcpu_svm * svm)1011 static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
1012 {
1013 unsigned port, size, iopm_len;
1014 u16 val, mask;
1015 u8 start_bit;
1016 u64 gpa;
1017
1018 if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
1019 return NESTED_EXIT_HOST;
1020
1021 port = svm->vmcb->control.exit_info_1 >> 16;
1022 size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >>
1023 SVM_IOIO_SIZE_SHIFT;
1024 gpa = svm->nested.ctl.iopm_base_pa + (port / 8);
1025 start_bit = port % 8;
1026 iopm_len = (start_bit + size > 8) ? 2 : 1;
1027 mask = (0xf >> (4 - size)) << start_bit;
1028 val = 0;
1029
1030 if (kvm_vcpu_read_guest(&svm->vcpu, gpa, &val, iopm_len))
1031 return NESTED_EXIT_DONE;
1032
1033 return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST;
1034 }
1035
nested_svm_intercept(struct vcpu_svm * svm)1036 static int nested_svm_intercept(struct vcpu_svm *svm)
1037 {
1038 u32 exit_code = svm->vmcb->control.exit_code;
1039 int vmexit = NESTED_EXIT_HOST;
1040
1041 switch (exit_code) {
1042 case SVM_EXIT_MSR:
1043 vmexit = nested_svm_exit_handled_msr(svm);
1044 break;
1045 case SVM_EXIT_IOIO:
1046 vmexit = nested_svm_intercept_ioio(svm);
1047 break;
1048 case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
1049 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
1050 vmexit = NESTED_EXIT_DONE;
1051 break;
1052 }
1053 case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
1054 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
1055 vmexit = NESTED_EXIT_DONE;
1056 break;
1057 }
1058 case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1059 /*
1060 * Host-intercepted exceptions have been checked already in
1061 * nested_svm_exit_special. There is nothing to do here,
1062 * the vmexit is injected by svm_check_nested_events.
1063 */
1064 vmexit = NESTED_EXIT_DONE;
1065 break;
1066 }
1067 case SVM_EXIT_ERR: {
1068 vmexit = NESTED_EXIT_DONE;
1069 break;
1070 }
1071 default: {
1072 if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
1073 vmexit = NESTED_EXIT_DONE;
1074 }
1075 }
1076
1077 return vmexit;
1078 }
1079
nested_svm_exit_handled(struct vcpu_svm * svm)1080 int nested_svm_exit_handled(struct vcpu_svm *svm)
1081 {
1082 int vmexit;
1083
1084 vmexit = nested_svm_intercept(svm);
1085
1086 if (vmexit == NESTED_EXIT_DONE)
1087 nested_svm_vmexit(svm);
1088
1089 return vmexit;
1090 }
1091
nested_svm_check_permissions(struct kvm_vcpu * vcpu)1092 int nested_svm_check_permissions(struct kvm_vcpu *vcpu)
1093 {
1094 if (!(vcpu->arch.efer & EFER_SVME) || !is_paging(vcpu)) {
1095 kvm_queue_exception(vcpu, UD_VECTOR);
1096 return 1;
1097 }
1098
1099 if (to_svm(vcpu)->vmcb->save.cpl) {
1100 kvm_inject_gp(vcpu, 0);
1101 return 1;
1102 }
1103
1104 return 0;
1105 }
1106
nested_exit_on_exception(struct vcpu_svm * svm)1107 static bool nested_exit_on_exception(struct vcpu_svm *svm)
1108 {
1109 unsigned int nr = svm->vcpu.arch.exception.nr;
1110
1111 return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(nr));
1112 }
1113
nested_svm_inject_exception_vmexit(struct vcpu_svm * svm)1114 static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm)
1115 {
1116 unsigned int nr = svm->vcpu.arch.exception.nr;
1117
1118 svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
1119 svm->vmcb->control.exit_code_hi = 0;
1120
1121 if (svm->vcpu.arch.exception.has_error_code)
1122 svm->vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code;
1123
1124 /*
1125 * EXITINFO2 is undefined for all exception intercepts other
1126 * than #PF.
1127 */
1128 if (nr == PF_VECTOR) {
1129 if (svm->vcpu.arch.exception.nested_apf)
1130 svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token;
1131 else if (svm->vcpu.arch.exception.has_payload)
1132 svm->vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload;
1133 else
1134 svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2;
1135 } else if (nr == DB_VECTOR) {
1136 /* See inject_pending_event. */
1137 kvm_deliver_exception_payload(&svm->vcpu);
1138 if (svm->vcpu.arch.dr7 & DR7_GD) {
1139 svm->vcpu.arch.dr7 &= ~DR7_GD;
1140 kvm_update_dr7(&svm->vcpu);
1141 }
1142 } else
1143 WARN_ON(svm->vcpu.arch.exception.has_payload);
1144
1145 nested_svm_vmexit(svm);
1146 }
1147
nested_exit_on_init(struct vcpu_svm * svm)1148 static inline bool nested_exit_on_init(struct vcpu_svm *svm)
1149 {
1150 return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
1151 }
1152
svm_check_nested_events(struct kvm_vcpu * vcpu)1153 static int svm_check_nested_events(struct kvm_vcpu *vcpu)
1154 {
1155 struct vcpu_svm *svm = to_svm(vcpu);
1156 bool block_nested_events =
1157 kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending;
1158 struct kvm_lapic *apic = vcpu->arch.apic;
1159
1160 if (lapic_in_kernel(vcpu) &&
1161 test_bit(KVM_APIC_INIT, &apic->pending_events)) {
1162 if (block_nested_events)
1163 return -EBUSY;
1164 if (!nested_exit_on_init(svm))
1165 return 0;
1166 nested_svm_simple_vmexit(svm, SVM_EXIT_INIT);
1167 return 0;
1168 }
1169
1170 if (vcpu->arch.exception.pending) {
1171 /*
1172 * Only a pending nested run can block a pending exception.
1173 * Otherwise an injected NMI/interrupt should either be
1174 * lost or delivered to the nested hypervisor in the EXITINTINFO
1175 * vmcb field, while delivering the pending exception.
1176 */
1177 if (svm->nested.nested_run_pending)
1178 return -EBUSY;
1179 if (!nested_exit_on_exception(svm))
1180 return 0;
1181 nested_svm_inject_exception_vmexit(svm);
1182 return 0;
1183 }
1184
1185 if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
1186 if (block_nested_events)
1187 return -EBUSY;
1188 if (!nested_exit_on_smi(svm))
1189 return 0;
1190 nested_svm_simple_vmexit(svm, SVM_EXIT_SMI);
1191 return 0;
1192 }
1193
1194 if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
1195 if (block_nested_events)
1196 return -EBUSY;
1197 if (!nested_exit_on_nmi(svm))
1198 return 0;
1199 nested_svm_simple_vmexit(svm, SVM_EXIT_NMI);
1200 return 0;
1201 }
1202
1203 if (kvm_cpu_has_interrupt(vcpu) && !svm_interrupt_blocked(vcpu)) {
1204 if (block_nested_events)
1205 return -EBUSY;
1206 if (!nested_exit_on_intr(svm))
1207 return 0;
1208 trace_kvm_nested_intr_vmexit(svm->vmcb->save.rip);
1209 nested_svm_simple_vmexit(svm, SVM_EXIT_INTR);
1210 return 0;
1211 }
1212
1213 return 0;
1214 }
1215
nested_svm_exit_special(struct vcpu_svm * svm)1216 int nested_svm_exit_special(struct vcpu_svm *svm)
1217 {
1218 u32 exit_code = svm->vmcb->control.exit_code;
1219
1220 switch (exit_code) {
1221 case SVM_EXIT_INTR:
1222 case SVM_EXIT_NMI:
1223 case SVM_EXIT_NPF:
1224 return NESTED_EXIT_HOST;
1225 case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: {
1226 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
1227
1228 if (svm->vmcb01.ptr->control.intercepts[INTERCEPT_EXCEPTION] &
1229 excp_bits)
1230 return NESTED_EXIT_HOST;
1231 else if (exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR &&
1232 svm->vcpu.arch.apf.host_apf_flags)
1233 /* Trap async PF even if not shadowing */
1234 return NESTED_EXIT_HOST;
1235 break;
1236 }
1237 default:
1238 break;
1239 }
1240
1241 return NESTED_EXIT_CONTINUE;
1242 }
1243
nested_svm_update_tsc_ratio_msr(struct kvm_vcpu * vcpu)1244 void nested_svm_update_tsc_ratio_msr(struct kvm_vcpu *vcpu)
1245 {
1246 struct vcpu_svm *svm = to_svm(vcpu);
1247
1248 vcpu->arch.tsc_scaling_ratio =
1249 kvm_calc_nested_tsc_multiplier(vcpu->arch.l1_tsc_scaling_ratio,
1250 svm->tsc_ratio_msr);
1251 svm_write_tsc_multiplier(vcpu, vcpu->arch.tsc_scaling_ratio);
1252 }
1253
svm_get_nested_state(struct kvm_vcpu * vcpu,struct kvm_nested_state __user * user_kvm_nested_state,u32 user_data_size)1254 static int svm_get_nested_state(struct kvm_vcpu *vcpu,
1255 struct kvm_nested_state __user *user_kvm_nested_state,
1256 u32 user_data_size)
1257 {
1258 struct vcpu_svm *svm;
1259 struct kvm_nested_state kvm_state = {
1260 .flags = 0,
1261 .format = KVM_STATE_NESTED_FORMAT_SVM,
1262 .size = sizeof(kvm_state),
1263 };
1264 struct vmcb __user *user_vmcb = (struct vmcb __user *)
1265 &user_kvm_nested_state->data.svm[0];
1266
1267 if (!vcpu)
1268 return kvm_state.size + KVM_STATE_NESTED_SVM_VMCB_SIZE;
1269
1270 svm = to_svm(vcpu);
1271
1272 if (user_data_size < kvm_state.size)
1273 goto out;
1274
1275 /* First fill in the header and copy it out. */
1276 if (is_guest_mode(vcpu)) {
1277 kvm_state.hdr.svm.vmcb_pa = svm->nested.vmcb12_gpa;
1278 kvm_state.size += KVM_STATE_NESTED_SVM_VMCB_SIZE;
1279 kvm_state.flags |= KVM_STATE_NESTED_GUEST_MODE;
1280
1281 if (svm->nested.nested_run_pending)
1282 kvm_state.flags |= KVM_STATE_NESTED_RUN_PENDING;
1283 }
1284
1285 if (gif_set(svm))
1286 kvm_state.flags |= KVM_STATE_NESTED_GIF_SET;
1287
1288 if (copy_to_user(user_kvm_nested_state, &kvm_state, sizeof(kvm_state)))
1289 return -EFAULT;
1290
1291 if (!is_guest_mode(vcpu))
1292 goto out;
1293
1294 /*
1295 * Copy over the full size of the VMCB rather than just the size
1296 * of the structs.
1297 */
1298 if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
1299 return -EFAULT;
1300 if (copy_to_user(&user_vmcb->control, &svm->nested.ctl,
1301 sizeof(user_vmcb->control)))
1302 return -EFAULT;
1303 if (copy_to_user(&user_vmcb->save, &svm->vmcb01.ptr->save,
1304 sizeof(user_vmcb->save)))
1305 return -EFAULT;
1306 out:
1307 return kvm_state.size;
1308 }
1309
svm_set_nested_state(struct kvm_vcpu * vcpu,struct kvm_nested_state __user * user_kvm_nested_state,struct kvm_nested_state * kvm_state)1310 static int svm_set_nested_state(struct kvm_vcpu *vcpu,
1311 struct kvm_nested_state __user *user_kvm_nested_state,
1312 struct kvm_nested_state *kvm_state)
1313 {
1314 struct vcpu_svm *svm = to_svm(vcpu);
1315 struct vmcb __user *user_vmcb = (struct vmcb __user *)
1316 &user_kvm_nested_state->data.svm[0];
1317 struct vmcb_control_area *ctl;
1318 struct vmcb_save_area *save;
1319 unsigned long cr0;
1320 int ret;
1321
1322 BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct vmcb_save_area) >
1323 KVM_STATE_NESTED_SVM_VMCB_SIZE);
1324
1325 if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
1326 return -EINVAL;
1327
1328 if (kvm_state->flags & ~(KVM_STATE_NESTED_GUEST_MODE |
1329 KVM_STATE_NESTED_RUN_PENDING |
1330 KVM_STATE_NESTED_GIF_SET))
1331 return -EINVAL;
1332
1333 /*
1334 * If in guest mode, vcpu->arch.efer actually refers to the L2 guest's
1335 * EFER.SVME, but EFER.SVME still has to be 1 for VMRUN to succeed.
1336 */
1337 if (!(vcpu->arch.efer & EFER_SVME)) {
1338 /* GIF=1 and no guest mode are required if SVME=0. */
1339 if (kvm_state->flags != KVM_STATE_NESTED_GIF_SET)
1340 return -EINVAL;
1341 }
1342
1343 /* SMM temporarily disables SVM, so we cannot be in guest mode. */
1344 if (is_smm(vcpu) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE))
1345 return -EINVAL;
1346
1347 if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
1348 svm_leave_nested(svm);
1349 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1350 return 0;
1351 }
1352
1353 if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
1354 return -EINVAL;
1355 if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE)
1356 return -EINVAL;
1357
1358 ret = -ENOMEM;
1359 ctl = kzalloc(sizeof(*ctl), GFP_KERNEL_ACCOUNT);
1360 save = kzalloc(sizeof(*save), GFP_KERNEL_ACCOUNT);
1361 if (!ctl || !save)
1362 goto out_free;
1363
1364 ret = -EFAULT;
1365 if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl)))
1366 goto out_free;
1367 if (copy_from_user(save, &user_vmcb->save, sizeof(*save)))
1368 goto out_free;
1369
1370 ret = -EINVAL;
1371 if (!nested_vmcb_check_controls(vcpu, ctl))
1372 goto out_free;
1373
1374 /*
1375 * Processor state contains L2 state. Check that it is
1376 * valid for guest mode (see nested_vmcb_check_save).
1377 */
1378 cr0 = kvm_read_cr0(vcpu);
1379 if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
1380 goto out_free;
1381
1382 /*
1383 * Validate host state saved from before VMRUN (see
1384 * nested_svm_check_permissions).
1385 */
1386 if (!(save->cr0 & X86_CR0_PG) ||
1387 !(save->cr0 & X86_CR0_PE) ||
1388 (save->rflags & X86_EFLAGS_VM) ||
1389 !nested_vmcb_valid_sregs(vcpu, save))
1390 goto out_free;
1391
1392 /*
1393 * While the nested guest CR3 is already checked and set by
1394 * KVM_SET_SREGS, it was set when nested state was yet loaded,
1395 * thus MMU might not be initialized correctly.
1396 * Set it again to fix this.
1397 */
1398
1399 ret = nested_svm_load_cr3(&svm->vcpu, vcpu->arch.cr3,
1400 nested_npt_enabled(svm), false);
1401 if (WARN_ON_ONCE(ret))
1402 goto out_free;
1403
1404
1405 /*
1406 * All checks done, we can enter guest mode. Userspace provides
1407 * vmcb12.control, which will be combined with L1 and stored into
1408 * vmcb02, and the L1 save state which we store in vmcb01.
1409 * L2 registers if needed are moved from the current VMCB to VMCB02.
1410 */
1411
1412 if (is_guest_mode(vcpu))
1413 svm_leave_nested(svm);
1414 else
1415 svm->nested.vmcb02.ptr->save = svm->vmcb01.ptr->save;
1416
1417 svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
1418
1419 svm->nested.nested_run_pending =
1420 !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);
1421
1422 svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;
1423
1424 svm_copy_vmrun_state(&svm->vmcb01.ptr->save, save);
1425 nested_load_control_from_vmcb12(svm, ctl);
1426
1427 svm_switch_vmcb(svm, &svm->nested.vmcb02);
1428 nested_vmcb02_prepare_control(svm);
1429 kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
1430 ret = 0;
1431 out_free:
1432 kfree(save);
1433 kfree(ctl);
1434
1435 return ret;
1436 }
1437
svm_get_nested_state_pages(struct kvm_vcpu * vcpu)1438 static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
1439 {
1440 struct vcpu_svm *svm = to_svm(vcpu);
1441
1442 if (WARN_ON(!is_guest_mode(vcpu)))
1443 return true;
1444
1445 if (!vcpu->arch.pdptrs_from_userspace &&
1446 !nested_npt_enabled(svm) && is_pae_paging(vcpu))
1447 /*
1448 * Reload the guest's PDPTRs since after a migration
1449 * the guest CR3 might be restored prior to setting the nested
1450 * state which can lead to a load of wrong PDPTRs.
1451 */
1452 if (CC(!load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3)))
1453 return false;
1454
1455 if (!nested_svm_vmrun_msrpm(svm)) {
1456 vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1457 vcpu->run->internal.suberror =
1458 KVM_INTERNAL_ERROR_EMULATION;
1459 vcpu->run->internal.ndata = 0;
1460 return false;
1461 }
1462
1463 return true;
1464 }
1465
1466 struct kvm_x86_nested_ops svm_nested_ops = {
1467 .check_events = svm_check_nested_events,
1468 .triple_fault = nested_svm_triple_fault,
1469 .get_nested_state_pages = svm_get_nested_state_pages,
1470 .get_state = svm_get_nested_state,
1471 .set_state = svm_set_nested_state,
1472 };
1473