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kvm: vmx: Raise #UD on unsupported XSAVES/XRSTORS
[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kvm / cpuid.c
1 /*
2 * Kernel-based Virtual Machine driver for Linux
3 * cpuid support routines
4 *
5 * derived from arch/x86/kvm/x86.c
6 *
7 * Copyright 2011 Red Hat, Inc. and/or its affiliates.
8 * Copyright IBM Corporation, 2008
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2. See
11 * the COPYING file in the top-level directory.
12 *
13 */
14
15 #include <linux/kvm_host.h>
16 #include <linux/export.h>
17 #include <linux/vmalloc.h>
18 #include <linux/uaccess.h>
19 #include <linux/sched/stat.h>
20
21 #include <asm/processor.h>
22 #include <asm/user.h>
23 #include <asm/fpu/xstate.h>
24 #include "cpuid.h"
25 #include "lapic.h"
26 #include "mmu.h"
27 #include "trace.h"
28 #include "pmu.h"
29
30 static u32 xstate_required_size(u64 xstate_bv, bool compacted)
31 {
32 int feature_bit = 0;
33 u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
34
35 xstate_bv &= XFEATURE_MASK_EXTEND;
36 while (xstate_bv) {
37 if (xstate_bv & 0x1) {
38 u32 eax, ebx, ecx, edx, offset;
39 cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx);
40 offset = compacted ? ret : ebx;
41 ret = max(ret, offset + eax);
42 }
43
44 xstate_bv >>= 1;
45 feature_bit++;
46 }
47
48 return ret;
49 }
50
51 bool kvm_mpx_supported(void)
52 {
53 return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
54 && kvm_x86_ops->mpx_supported());
55 }
56 EXPORT_SYMBOL_GPL(kvm_mpx_supported);
57
58 u64 kvm_supported_xcr0(void)
59 {
60 u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
61
62 if (!kvm_mpx_supported())
63 xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
64
65 return xcr0;
66 }
67
68 #define F(x) bit(X86_FEATURE_##x)
69
70 /* These are scattered features in cpufeatures.h. */
71 #define KVM_CPUID_BIT_AVX512_4VNNIW 2
72 #define KVM_CPUID_BIT_AVX512_4FMAPS 3
73 #define KF(x) bit(KVM_CPUID_BIT_##x)
74
75 int kvm_update_cpuid(struct kvm_vcpu *vcpu)
76 {
77 struct kvm_cpuid_entry2 *best;
78 struct kvm_lapic *apic = vcpu->arch.apic;
79
80 best = kvm_find_cpuid_entry(vcpu, 1, 0);
81 if (!best)
82 return 0;
83
84 /* Update OSXSAVE bit */
85 if (boot_cpu_has(X86_FEATURE_XSAVE) && best->function == 0x1) {
86 best->ecx &= ~F(OSXSAVE);
87 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
88 best->ecx |= F(OSXSAVE);
89 }
90
91 best->edx &= ~F(APIC);
92 if (vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE)
93 best->edx |= F(APIC);
94
95 if (apic) {
96 if (best->ecx & F(TSC_DEADLINE_TIMER))
97 apic->lapic_timer.timer_mode_mask = 3 << 17;
98 else
99 apic->lapic_timer.timer_mode_mask = 1 << 17;
100 }
101
102 best = kvm_find_cpuid_entry(vcpu, 7, 0);
103 if (best) {
104 /* Update OSPKE bit */
105 if (boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) {
106 best->ecx &= ~F(OSPKE);
107 if (kvm_read_cr4_bits(vcpu, X86_CR4_PKE))
108 best->ecx |= F(OSPKE);
109 }
110 }
111
112 best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
113 if (!best) {
114 vcpu->arch.guest_supported_xcr0 = 0;
115 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
116 } else {
117 vcpu->arch.guest_supported_xcr0 =
118 (best->eax | ((u64)best->edx << 32)) &
119 kvm_supported_xcr0();
120 vcpu->arch.guest_xstate_size = best->ebx =
121 xstate_required_size(vcpu->arch.xcr0, false);
122 }
123
124 best = kvm_find_cpuid_entry(vcpu, 0xD, 1);
125 if (best && (best->eax & (F(XSAVES) | F(XSAVEC))))
126 best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
127
128 /*
129 * The existing code assumes virtual address is 48-bit in the canonical
130 * address checks; exit if it is ever changed.
131 */
132 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
133 if (best && ((best->eax & 0xff00) >> 8) != 48 &&
134 ((best->eax & 0xff00) >> 8) != 0)
135 return -EINVAL;
136
137 /* Update physical-address width */
138 vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
139
140 kvm_pmu_refresh(vcpu);
141 return 0;
142 }
143
144 static int is_efer_nx(void)
145 {
146 unsigned long long efer = 0;
147
148 rdmsrl_safe(MSR_EFER, &efer);
149 return efer & EFER_NX;
150 }
151
152 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
153 {
154 int i;
155 struct kvm_cpuid_entry2 *e, *entry;
156
157 entry = NULL;
158 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
159 e = &vcpu->arch.cpuid_entries[i];
160 if (e->function == 0x80000001) {
161 entry = e;
162 break;
163 }
164 }
165 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
166 entry->edx &= ~F(NX);
167 printk(KERN_INFO "kvm: guest NX capability removed\n");
168 }
169 }
170
171 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
172 {
173 struct kvm_cpuid_entry2 *best;
174
175 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
176 if (!best || best->eax < 0x80000008)
177 goto not_found;
178 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
179 if (best)
180 return best->eax & 0xff;
181 not_found:
182 return 36;
183 }
184 EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
185
186 /* when an old userspace process fills a new kernel module */
187 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
188 struct kvm_cpuid *cpuid,
189 struct kvm_cpuid_entry __user *entries)
190 {
191 int r, i;
192 struct kvm_cpuid_entry *cpuid_entries = NULL;
193
194 r = -E2BIG;
195 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
196 goto out;
197 r = -ENOMEM;
198 if (cpuid->nent) {
199 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) *
200 cpuid->nent);
201 if (!cpuid_entries)
202 goto out;
203 r = -EFAULT;
204 if (copy_from_user(cpuid_entries, entries,
205 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
206 goto out;
207 }
208 for (i = 0; i < cpuid->nent; i++) {
209 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
210 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
211 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
212 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
213 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
214 vcpu->arch.cpuid_entries[i].index = 0;
215 vcpu->arch.cpuid_entries[i].flags = 0;
216 vcpu->arch.cpuid_entries[i].padding[0] = 0;
217 vcpu->arch.cpuid_entries[i].padding[1] = 0;
218 vcpu->arch.cpuid_entries[i].padding[2] = 0;
219 }
220 vcpu->arch.cpuid_nent = cpuid->nent;
221 cpuid_fix_nx_cap(vcpu);
222 kvm_apic_set_version(vcpu);
223 kvm_x86_ops->cpuid_update(vcpu);
224 r = kvm_update_cpuid(vcpu);
225
226 out:
227 vfree(cpuid_entries);
228 return r;
229 }
230
231 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
232 struct kvm_cpuid2 *cpuid,
233 struct kvm_cpuid_entry2 __user *entries)
234 {
235 int r;
236
237 r = -E2BIG;
238 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
239 goto out;
240 r = -EFAULT;
241 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
242 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
243 goto out;
244 vcpu->arch.cpuid_nent = cpuid->nent;
245 kvm_apic_set_version(vcpu);
246 kvm_x86_ops->cpuid_update(vcpu);
247 r = kvm_update_cpuid(vcpu);
248 out:
249 return r;
250 }
251
252 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
253 struct kvm_cpuid2 *cpuid,
254 struct kvm_cpuid_entry2 __user *entries)
255 {
256 int r;
257
258 r = -E2BIG;
259 if (cpuid->nent < vcpu->arch.cpuid_nent)
260 goto out;
261 r = -EFAULT;
262 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
263 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
264 goto out;
265 return 0;
266
267 out:
268 cpuid->nent = vcpu->arch.cpuid_nent;
269 return r;
270 }
271
272 static void cpuid_mask(u32 *word, int wordnum)
273 {
274 *word &= boot_cpu_data.x86_capability[wordnum];
275 }
276
277 static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
278 u32 index)
279 {
280 entry->function = function;
281 entry->index = index;
282 cpuid_count(entry->function, entry->index,
283 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
284 entry->flags = 0;
285 }
286
287 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
288 u32 func, u32 index, int *nent, int maxnent)
289 {
290 switch (func) {
291 case 0:
292 entry->eax = 1; /* only one leaf currently */
293 ++*nent;
294 break;
295 case 1:
296 entry->ecx = F(MOVBE);
297 ++*nent;
298 break;
299 default:
300 break;
301 }
302
303 entry->function = func;
304 entry->index = index;
305
306 return 0;
307 }
308
309 static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
310 u32 index, int *nent, int maxnent)
311 {
312 int r;
313 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
314 #ifdef CONFIG_X86_64
315 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
316 ? F(GBPAGES) : 0;
317 unsigned f_lm = F(LM);
318 #else
319 unsigned f_gbpages = 0;
320 unsigned f_lm = 0;
321 #endif
322 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
323 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
324 unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
325 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
326
327 /* cpuid 1.edx */
328 const u32 kvm_cpuid_1_edx_x86_features =
329 F(FPU) | F(VME) | F(DE) | F(PSE) |
330 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
331 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
332 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
333 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
334 0 /* Reserved, DS, ACPI */ | F(MMX) |
335 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
336 0 /* HTT, TM, Reserved, PBE */;
337 /* cpuid 0x80000001.edx */
338 const u32 kvm_cpuid_8000_0001_edx_x86_features =
339 F(FPU) | F(VME) | F(DE) | F(PSE) |
340 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
341 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) |
342 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
343 F(PAT) | F(PSE36) | 0 /* Reserved */ |
344 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
345 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
346 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
347 /* cpuid 1.ecx */
348 const u32 kvm_cpuid_1_ecx_x86_features =
349 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
350 * but *not* advertised to guests via CPUID ! */
351 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
352 0 /* DS-CPL, VMX, SMX, EST */ |
353 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
354 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
355 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
356 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
357 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
358 F(F16C) | F(RDRAND);
359 /* cpuid 0x80000001.ecx */
360 const u32 kvm_cpuid_8000_0001_ecx_x86_features =
361 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
362 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
363 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
364 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
365
366 /* cpuid 0xC0000001.edx */
367 const u32 kvm_cpuid_C000_0001_edx_x86_features =
368 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
369 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
370 F(PMM) | F(PMM_EN);
371
372 /* cpuid 7.0.ebx */
373 const u32 kvm_cpuid_7_0_ebx_x86_features =
374 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
375 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
376 F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) |
377 F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) |
378 F(SHA_NI) | F(AVX512BW) | F(AVX512VL);
379
380 /* cpuid 0xD.1.eax */
381 const u32 kvm_cpuid_D_1_eax_x86_features =
382 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
383
384 /* cpuid 7.0.ecx*/
385 const u32 kvm_cpuid_7_0_ecx_x86_features =
386 F(AVX512VBMI) | F(PKU) | 0 /*OSPKE*/ | F(AVX512_VPOPCNTDQ);
387
388 /* cpuid 7.0.edx*/
389 const u32 kvm_cpuid_7_0_edx_x86_features =
390 KF(AVX512_4VNNIW) | KF(AVX512_4FMAPS);
391
392 /* all calls to cpuid_count() should be made on the same cpu */
393 get_cpu();
394
395 r = -E2BIG;
396
397 if (*nent >= maxnent)
398 goto out;
399
400 do_cpuid_1_ent(entry, function, index);
401 ++*nent;
402
403 switch (function) {
404 case 0:
405 entry->eax = min(entry->eax, (u32)0xd);
406 break;
407 case 1:
408 entry->edx &= kvm_cpuid_1_edx_x86_features;
409 cpuid_mask(&entry->edx, CPUID_1_EDX);
410 entry->ecx &= kvm_cpuid_1_ecx_x86_features;
411 cpuid_mask(&entry->ecx, CPUID_1_ECX);
412 /* we support x2apic emulation even if host does not support
413 * it since we emulate x2apic in software */
414 entry->ecx |= F(X2APIC);
415 break;
416 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
417 * may return different values. This forces us to get_cpu() before
418 * issuing the first command, and also to emulate this annoying behavior
419 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
420 case 2: {
421 int t, times = entry->eax & 0xff;
422
423 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
424 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
425 for (t = 1; t < times; ++t) {
426 if (*nent >= maxnent)
427 goto out;
428
429 do_cpuid_1_ent(&entry[t], function, 0);
430 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
431 ++*nent;
432 }
433 break;
434 }
435 /* function 4 has additional index. */
436 case 4: {
437 int i, cache_type;
438
439 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
440 /* read more entries until cache_type is zero */
441 for (i = 1; ; ++i) {
442 if (*nent >= maxnent)
443 goto out;
444
445 cache_type = entry[i - 1].eax & 0x1f;
446 if (!cache_type)
447 break;
448 do_cpuid_1_ent(&entry[i], function, i);
449 entry[i].flags |=
450 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
451 ++*nent;
452 }
453 break;
454 }
455 case 6: /* Thermal management */
456 entry->eax = 0x4; /* allow ARAT */
457 entry->ebx = 0;
458 entry->ecx = 0;
459 entry->edx = 0;
460 break;
461 case 7: {
462 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
463 /* Mask ebx against host capability word 9 */
464 if (index == 0) {
465 entry->ebx &= kvm_cpuid_7_0_ebx_x86_features;
466 cpuid_mask(&entry->ebx, CPUID_7_0_EBX);
467 // TSC_ADJUST is emulated
468 entry->ebx |= F(TSC_ADJUST);
469 entry->ecx &= kvm_cpuid_7_0_ecx_x86_features;
470 cpuid_mask(&entry->ecx, CPUID_7_ECX);
471 /* PKU is not yet implemented for shadow paging. */
472 if (!tdp_enabled)
473 entry->ecx &= ~F(PKU);
474 entry->edx &= kvm_cpuid_7_0_edx_x86_features;
475 entry->edx &= get_scattered_cpuid_leaf(7, 0, CPUID_EDX);
476 } else {
477 entry->ebx = 0;
478 entry->ecx = 0;
479 entry->edx = 0;
480 }
481 entry->eax = 0;
482 break;
483 }
484 case 9:
485 break;
486 case 0xa: { /* Architectural Performance Monitoring */
487 struct x86_pmu_capability cap;
488 union cpuid10_eax eax;
489 union cpuid10_edx edx;
490
491 perf_get_x86_pmu_capability(&cap);
492
493 /*
494 * Only support guest architectural pmu on a host
495 * with architectural pmu.
496 */
497 if (!cap.version)
498 memset(&cap, 0, sizeof(cap));
499
500 eax.split.version_id = min(cap.version, 2);
501 eax.split.num_counters = cap.num_counters_gp;
502 eax.split.bit_width = cap.bit_width_gp;
503 eax.split.mask_length = cap.events_mask_len;
504
505 edx.split.num_counters_fixed = cap.num_counters_fixed;
506 edx.split.bit_width_fixed = cap.bit_width_fixed;
507 edx.split.reserved = 0;
508
509 entry->eax = eax.full;
510 entry->ebx = cap.events_mask;
511 entry->ecx = 0;
512 entry->edx = edx.full;
513 break;
514 }
515 /* function 0xb has additional index. */
516 case 0xb: {
517 int i, level_type;
518
519 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
520 /* read more entries until level_type is zero */
521 for (i = 1; ; ++i) {
522 if (*nent >= maxnent)
523 goto out;
524
525 level_type = entry[i - 1].ecx & 0xff00;
526 if (!level_type)
527 break;
528 do_cpuid_1_ent(&entry[i], function, i);
529 entry[i].flags |=
530 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
531 ++*nent;
532 }
533 break;
534 }
535 case 0xd: {
536 int idx, i;
537 u64 supported = kvm_supported_xcr0();
538
539 entry->eax &= supported;
540 entry->ebx = xstate_required_size(supported, false);
541 entry->ecx = entry->ebx;
542 entry->edx &= supported >> 32;
543 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
544 if (!supported)
545 break;
546
547 for (idx = 1, i = 1; idx < 64; ++idx) {
548 u64 mask = ((u64)1 << idx);
549 if (*nent >= maxnent)
550 goto out;
551
552 do_cpuid_1_ent(&entry[i], function, idx);
553 if (idx == 1) {
554 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
555 cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
556 entry[i].ebx = 0;
557 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
558 entry[i].ebx =
559 xstate_required_size(supported,
560 true);
561 } else {
562 if (entry[i].eax == 0 || !(supported & mask))
563 continue;
564 if (WARN_ON_ONCE(entry[i].ecx & 1))
565 continue;
566 }
567 entry[i].ecx = 0;
568 entry[i].edx = 0;
569 entry[i].flags |=
570 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
571 ++*nent;
572 ++i;
573 }
574 break;
575 }
576 case KVM_CPUID_SIGNATURE: {
577 static const char signature[12] = "KVMKVMKVM\0\0";
578 const u32 *sigptr = (const u32 *)signature;
579 entry->eax = KVM_CPUID_FEATURES;
580 entry->ebx = sigptr[0];
581 entry->ecx = sigptr[1];
582 entry->edx = sigptr[2];
583 break;
584 }
585 case KVM_CPUID_FEATURES:
586 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
587 (1 << KVM_FEATURE_NOP_IO_DELAY) |
588 (1 << KVM_FEATURE_CLOCKSOURCE2) |
589 (1 << KVM_FEATURE_ASYNC_PF) |
590 (1 << KVM_FEATURE_PV_EOI) |
591 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
592 (1 << KVM_FEATURE_PV_UNHALT);
593
594 if (sched_info_on())
595 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
596
597 entry->ebx = 0;
598 entry->ecx = 0;
599 entry->edx = 0;
600 break;
601 case 0x80000000:
602 entry->eax = min(entry->eax, 0x8000001a);
603 break;
604 case 0x80000001:
605 entry->edx &= kvm_cpuid_8000_0001_edx_x86_features;
606 cpuid_mask(&entry->edx, CPUID_8000_0001_EDX);
607 entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features;
608 cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX);
609 break;
610 case 0x80000007: /* Advanced power management */
611 /* invariant TSC is CPUID.80000007H:EDX[8] */
612 entry->edx &= (1 << 8);
613 /* mask against host */
614 entry->edx &= boot_cpu_data.x86_power;
615 entry->eax = entry->ebx = entry->ecx = 0;
616 break;
617 case 0x80000008: {
618 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
619 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
620 unsigned phys_as = entry->eax & 0xff;
621
622 if (!g_phys_as)
623 g_phys_as = phys_as;
624 entry->eax = g_phys_as | (virt_as << 8);
625 entry->ebx = entry->edx = 0;
626 break;
627 }
628 case 0x80000019:
629 entry->ecx = entry->edx = 0;
630 break;
631 case 0x8000001a:
632 break;
633 case 0x8000001d:
634 break;
635 /*Add support for Centaur's CPUID instruction*/
636 case 0xC0000000:
637 /*Just support up to 0xC0000004 now*/
638 entry->eax = min(entry->eax, 0xC0000004);
639 break;
640 case 0xC0000001:
641 entry->edx &= kvm_cpuid_C000_0001_edx_x86_features;
642 cpuid_mask(&entry->edx, CPUID_C000_0001_EDX);
643 break;
644 case 3: /* Processor serial number */
645 case 5: /* MONITOR/MWAIT */
646 case 0xC0000002:
647 case 0xC0000003:
648 case 0xC0000004:
649 default:
650 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
651 break;
652 }
653
654 kvm_x86_ops->set_supported_cpuid(function, entry);
655
656 r = 0;
657
658 out:
659 put_cpu();
660
661 return r;
662 }
663
664 static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
665 u32 idx, int *nent, int maxnent, unsigned int type)
666 {
667 if (type == KVM_GET_EMULATED_CPUID)
668 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
669
670 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
671 }
672
673 #undef F
674
675 struct kvm_cpuid_param {
676 u32 func;
677 u32 idx;
678 bool has_leaf_count;
679 bool (*qualifier)(const struct kvm_cpuid_param *param);
680 };
681
682 static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
683 {
684 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
685 }
686
687 static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
688 __u32 num_entries, unsigned int ioctl_type)
689 {
690 int i;
691 __u32 pad[3];
692
693 if (ioctl_type != KVM_GET_EMULATED_CPUID)
694 return false;
695
696 /*
697 * We want to make sure that ->padding is being passed clean from
698 * userspace in case we want to use it for something in the future.
699 *
700 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
701 * have to give ourselves satisfied only with the emulated side. /me
702 * sheds a tear.
703 */
704 for (i = 0; i < num_entries; i++) {
705 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
706 return true;
707
708 if (pad[0] || pad[1] || pad[2])
709 return true;
710 }
711 return false;
712 }
713
714 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
715 struct kvm_cpuid_entry2 __user *entries,
716 unsigned int type)
717 {
718 struct kvm_cpuid_entry2 *cpuid_entries;
719 int limit, nent = 0, r = -E2BIG, i;
720 u32 func;
721 static const struct kvm_cpuid_param param[] = {
722 { .func = 0, .has_leaf_count = true },
723 { .func = 0x80000000, .has_leaf_count = true },
724 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
725 { .func = KVM_CPUID_SIGNATURE },
726 { .func = KVM_CPUID_FEATURES },
727 };
728
729 if (cpuid->nent < 1)
730 goto out;
731 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
732 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
733
734 if (sanity_check_entries(entries, cpuid->nent, type))
735 return -EINVAL;
736
737 r = -ENOMEM;
738 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
739 if (!cpuid_entries)
740 goto out;
741
742 r = 0;
743 for (i = 0; i < ARRAY_SIZE(param); i++) {
744 const struct kvm_cpuid_param *ent = &param[i];
745
746 if (ent->qualifier && !ent->qualifier(ent))
747 continue;
748
749 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
750 &nent, cpuid->nent, type);
751
752 if (r)
753 goto out_free;
754
755 if (!ent->has_leaf_count)
756 continue;
757
758 limit = cpuid_entries[nent - 1].eax;
759 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
760 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
761 &nent, cpuid->nent, type);
762
763 if (r)
764 goto out_free;
765 }
766
767 r = -EFAULT;
768 if (copy_to_user(entries, cpuid_entries,
769 nent * sizeof(struct kvm_cpuid_entry2)))
770 goto out_free;
771 cpuid->nent = nent;
772 r = 0;
773
774 out_free:
775 vfree(cpuid_entries);
776 out:
777 return r;
778 }
779
780 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
781 {
782 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
783 struct kvm_cpuid_entry2 *ej;
784 int j = i;
785 int nent = vcpu->arch.cpuid_nent;
786
787 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
788 /* when no next entry is found, the current entry[i] is reselected */
789 do {
790 j = (j + 1) % nent;
791 ej = &vcpu->arch.cpuid_entries[j];
792 } while (ej->function != e->function);
793
794 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
795
796 return j;
797 }
798
799 /* find an entry with matching function, matching index (if needed), and that
800 * should be read next (if it's stateful) */
801 static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
802 u32 function, u32 index)
803 {
804 if (e->function != function)
805 return 0;
806 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
807 return 0;
808 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
809 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
810 return 0;
811 return 1;
812 }
813
814 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
815 u32 function, u32 index)
816 {
817 int i;
818 struct kvm_cpuid_entry2 *best = NULL;
819
820 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
821 struct kvm_cpuid_entry2 *e;
822
823 e = &vcpu->arch.cpuid_entries[i];
824 if (is_matching_cpuid_entry(e, function, index)) {
825 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
826 move_to_next_stateful_cpuid_entry(vcpu, i);
827 best = e;
828 break;
829 }
830 }
831 return best;
832 }
833 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
834
835 /*
836 * If no match is found, check whether we exceed the vCPU's limit
837 * and return the content of the highest valid _standard_ leaf instead.
838 * This is to satisfy the CPUID specification.
839 */
840 static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
841 u32 function, u32 index)
842 {
843 struct kvm_cpuid_entry2 *maxlevel;
844
845 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
846 if (!maxlevel || maxlevel->eax >= function)
847 return NULL;
848 if (function & 0x80000000) {
849 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
850 if (!maxlevel)
851 return NULL;
852 }
853 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
854 }
855
856 void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
857 {
858 u32 function = *eax, index = *ecx;
859 struct kvm_cpuid_entry2 *best;
860
861 best = kvm_find_cpuid_entry(vcpu, function, index);
862
863 if (!best)
864 best = check_cpuid_limit(vcpu, function, index);
865
866 if (best) {
867 *eax = best->eax;
868 *ebx = best->ebx;
869 *ecx = best->ecx;
870 *edx = best->edx;
871 } else
872 *eax = *ebx = *ecx = *edx = 0;
873 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx);
874 }
875 EXPORT_SYMBOL_GPL(kvm_cpuid);
876
877 int kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
878 {
879 u32 eax, ebx, ecx, edx;
880
881 if (cpuid_fault_enabled(vcpu) && !kvm_require_cpl(vcpu, 0))
882 return 1;
883
884 eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
885 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
886 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx);
887 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
888 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
889 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
890 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
891 return kvm_skip_emulated_instruction(vcpu);
892 }
893 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
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