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Merge tag 'trace-v4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
[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 or 57-bit in the
130 * canonical address checks; exit if it is ever changed.
131 */
132 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
133 if (best) {
134 int vaddr_bits = (best->eax & 0xff00) >> 8;
135
136 if (vaddr_bits != 48 && vaddr_bits != 57 && vaddr_bits != 0)
137 return -EINVAL;
138 }
139
140 /* Update physical-address width */
141 vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
142 kvm_mmu_reset_context(vcpu);
143
144 kvm_pmu_refresh(vcpu);
145 return 0;
146 }
147
148 static int is_efer_nx(void)
149 {
150 unsigned long long efer = 0;
151
152 rdmsrl_safe(MSR_EFER, &efer);
153 return efer & EFER_NX;
154 }
155
156 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
157 {
158 int i;
159 struct kvm_cpuid_entry2 *e, *entry;
160
161 entry = NULL;
162 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
163 e = &vcpu->arch.cpuid_entries[i];
164 if (e->function == 0x80000001) {
165 entry = e;
166 break;
167 }
168 }
169 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
170 entry->edx &= ~F(NX);
171 printk(KERN_INFO "kvm: guest NX capability removed\n");
172 }
173 }
174
175 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
176 {
177 struct kvm_cpuid_entry2 *best;
178
179 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
180 if (!best || best->eax < 0x80000008)
181 goto not_found;
182 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
183 if (best)
184 return best->eax & 0xff;
185 not_found:
186 return 36;
187 }
188 EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
189
190 /* when an old userspace process fills a new kernel module */
191 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
192 struct kvm_cpuid *cpuid,
193 struct kvm_cpuid_entry __user *entries)
194 {
195 int r, i;
196 struct kvm_cpuid_entry *cpuid_entries = NULL;
197
198 r = -E2BIG;
199 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
200 goto out;
201 r = -ENOMEM;
202 if (cpuid->nent) {
203 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) *
204 cpuid->nent);
205 if (!cpuid_entries)
206 goto out;
207 r = -EFAULT;
208 if (copy_from_user(cpuid_entries, entries,
209 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
210 goto out;
211 }
212 for (i = 0; i < cpuid->nent; i++) {
213 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
214 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
215 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
216 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
217 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
218 vcpu->arch.cpuid_entries[i].index = 0;
219 vcpu->arch.cpuid_entries[i].flags = 0;
220 vcpu->arch.cpuid_entries[i].padding[0] = 0;
221 vcpu->arch.cpuid_entries[i].padding[1] = 0;
222 vcpu->arch.cpuid_entries[i].padding[2] = 0;
223 }
224 vcpu->arch.cpuid_nent = cpuid->nent;
225 cpuid_fix_nx_cap(vcpu);
226 kvm_apic_set_version(vcpu);
227 kvm_x86_ops->cpuid_update(vcpu);
228 r = kvm_update_cpuid(vcpu);
229
230 out:
231 vfree(cpuid_entries);
232 return r;
233 }
234
235 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
236 struct kvm_cpuid2 *cpuid,
237 struct kvm_cpuid_entry2 __user *entries)
238 {
239 int r;
240
241 r = -E2BIG;
242 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
243 goto out;
244 r = -EFAULT;
245 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
246 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
247 goto out;
248 vcpu->arch.cpuid_nent = cpuid->nent;
249 kvm_apic_set_version(vcpu);
250 kvm_x86_ops->cpuid_update(vcpu);
251 r = kvm_update_cpuid(vcpu);
252 out:
253 return r;
254 }
255
256 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
257 struct kvm_cpuid2 *cpuid,
258 struct kvm_cpuid_entry2 __user *entries)
259 {
260 int r;
261
262 r = -E2BIG;
263 if (cpuid->nent < vcpu->arch.cpuid_nent)
264 goto out;
265 r = -EFAULT;
266 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
267 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
268 goto out;
269 return 0;
270
271 out:
272 cpuid->nent = vcpu->arch.cpuid_nent;
273 return r;
274 }
275
276 static void cpuid_mask(u32 *word, int wordnum)
277 {
278 *word &= boot_cpu_data.x86_capability[wordnum];
279 }
280
281 static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
282 u32 index)
283 {
284 entry->function = function;
285 entry->index = index;
286 cpuid_count(entry->function, entry->index,
287 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
288 entry->flags = 0;
289 }
290
291 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
292 u32 func, u32 index, int *nent, int maxnent)
293 {
294 switch (func) {
295 case 0:
296 entry->eax = 1; /* only one leaf currently */
297 ++*nent;
298 break;
299 case 1:
300 entry->ecx = F(MOVBE);
301 ++*nent;
302 break;
303 default:
304 break;
305 }
306
307 entry->function = func;
308 entry->index = index;
309
310 return 0;
311 }
312
313 static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
314 u32 index, int *nent, int maxnent)
315 {
316 int r;
317 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
318 #ifdef CONFIG_X86_64
319 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
320 ? F(GBPAGES) : 0;
321 unsigned f_lm = F(LM);
322 #else
323 unsigned f_gbpages = 0;
324 unsigned f_lm = 0;
325 #endif
326 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
327 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
328 unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
329 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
330
331 /* cpuid 1.edx */
332 const u32 kvm_cpuid_1_edx_x86_features =
333 F(FPU) | F(VME) | F(DE) | F(PSE) |
334 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
335 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
336 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
337 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
338 0 /* Reserved, DS, ACPI */ | F(MMX) |
339 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
340 0 /* HTT, TM, Reserved, PBE */;
341 /* cpuid 0x80000001.edx */
342 const u32 kvm_cpuid_8000_0001_edx_x86_features =
343 F(FPU) | F(VME) | F(DE) | F(PSE) |
344 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
345 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) |
346 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
347 F(PAT) | F(PSE36) | 0 /* Reserved */ |
348 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
349 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
350 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
351 /* cpuid 1.ecx */
352 const u32 kvm_cpuid_1_ecx_x86_features =
353 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
354 * but *not* advertised to guests via CPUID ! */
355 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
356 0 /* DS-CPL, VMX, SMX, EST */ |
357 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
358 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
359 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
360 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
361 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
362 F(F16C) | F(RDRAND);
363 /* cpuid 0x80000001.ecx */
364 const u32 kvm_cpuid_8000_0001_ecx_x86_features =
365 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
366 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
367 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
368 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
369
370 /* cpuid 0xC0000001.edx */
371 const u32 kvm_cpuid_C000_0001_edx_x86_features =
372 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
373 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
374 F(PMM) | F(PMM_EN);
375
376 /* cpuid 7.0.ebx */
377 const u32 kvm_cpuid_7_0_ebx_x86_features =
378 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
379 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
380 F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) |
381 F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) |
382 F(SHA_NI) | F(AVX512BW) | F(AVX512VL);
383
384 /* cpuid 0xD.1.eax */
385 const u32 kvm_cpuid_D_1_eax_x86_features =
386 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
387
388 /* cpuid 7.0.ecx*/
389 const u32 kvm_cpuid_7_0_ecx_x86_features =
390 F(AVX512VBMI) | F(LA57) | F(PKU) |
391 0 /*OSPKE*/ | F(AVX512_VPOPCNTDQ);
392
393 /* cpuid 7.0.edx*/
394 const u32 kvm_cpuid_7_0_edx_x86_features =
395 KF(AVX512_4VNNIW) | KF(AVX512_4FMAPS);
396
397 /* all calls to cpuid_count() should be made on the same cpu */
398 get_cpu();
399
400 r = -E2BIG;
401
402 if (*nent >= maxnent)
403 goto out;
404
405 do_cpuid_1_ent(entry, function, index);
406 ++*nent;
407
408 switch (function) {
409 case 0:
410 entry->eax = min(entry->eax, (u32)0xd);
411 break;
412 case 1:
413 entry->edx &= kvm_cpuid_1_edx_x86_features;
414 cpuid_mask(&entry->edx, CPUID_1_EDX);
415 entry->ecx &= kvm_cpuid_1_ecx_x86_features;
416 cpuid_mask(&entry->ecx, CPUID_1_ECX);
417 /* we support x2apic emulation even if host does not support
418 * it since we emulate x2apic in software */
419 entry->ecx |= F(X2APIC);
420 break;
421 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
422 * may return different values. This forces us to get_cpu() before
423 * issuing the first command, and also to emulate this annoying behavior
424 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
425 case 2: {
426 int t, times = entry->eax & 0xff;
427
428 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
429 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
430 for (t = 1; t < times; ++t) {
431 if (*nent >= maxnent)
432 goto out;
433
434 do_cpuid_1_ent(&entry[t], function, 0);
435 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
436 ++*nent;
437 }
438 break;
439 }
440 /* function 4 has additional index. */
441 case 4: {
442 int i, cache_type;
443
444 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
445 /* read more entries until cache_type is zero */
446 for (i = 1; ; ++i) {
447 if (*nent >= maxnent)
448 goto out;
449
450 cache_type = entry[i - 1].eax & 0x1f;
451 if (!cache_type)
452 break;
453 do_cpuid_1_ent(&entry[i], function, i);
454 entry[i].flags |=
455 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
456 ++*nent;
457 }
458 break;
459 }
460 case 6: /* Thermal management */
461 entry->eax = 0x4; /* allow ARAT */
462 entry->ebx = 0;
463 entry->ecx = 0;
464 entry->edx = 0;
465 break;
466 case 7: {
467 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
468 /* Mask ebx against host capability word 9 */
469 if (index == 0) {
470 entry->ebx &= kvm_cpuid_7_0_ebx_x86_features;
471 cpuid_mask(&entry->ebx, CPUID_7_0_EBX);
472 // TSC_ADJUST is emulated
473 entry->ebx |= F(TSC_ADJUST);
474 entry->ecx &= kvm_cpuid_7_0_ecx_x86_features;
475 cpuid_mask(&entry->ecx, CPUID_7_ECX);
476 /* PKU is not yet implemented for shadow paging. */
477 if (!tdp_enabled || !boot_cpu_has(X86_FEATURE_OSPKE))
478 entry->ecx &= ~F(PKU);
479 entry->edx &= kvm_cpuid_7_0_edx_x86_features;
480 entry->edx &= get_scattered_cpuid_leaf(7, 0, CPUID_EDX);
481 } else {
482 entry->ebx = 0;
483 entry->ecx = 0;
484 entry->edx = 0;
485 }
486 entry->eax = 0;
487 break;
488 }
489 case 9:
490 break;
491 case 0xa: { /* Architectural Performance Monitoring */
492 struct x86_pmu_capability cap;
493 union cpuid10_eax eax;
494 union cpuid10_edx edx;
495
496 perf_get_x86_pmu_capability(&cap);
497
498 /*
499 * Only support guest architectural pmu on a host
500 * with architectural pmu.
501 */
502 if (!cap.version)
503 memset(&cap, 0, sizeof(cap));
504
505 eax.split.version_id = min(cap.version, 2);
506 eax.split.num_counters = cap.num_counters_gp;
507 eax.split.bit_width = cap.bit_width_gp;
508 eax.split.mask_length = cap.events_mask_len;
509
510 edx.split.num_counters_fixed = cap.num_counters_fixed;
511 edx.split.bit_width_fixed = cap.bit_width_fixed;
512 edx.split.reserved = 0;
513
514 entry->eax = eax.full;
515 entry->ebx = cap.events_mask;
516 entry->ecx = 0;
517 entry->edx = edx.full;
518 break;
519 }
520 /* function 0xb has additional index. */
521 case 0xb: {
522 int i, level_type;
523
524 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
525 /* read more entries until level_type is zero */
526 for (i = 1; ; ++i) {
527 if (*nent >= maxnent)
528 goto out;
529
530 level_type = entry[i - 1].ecx & 0xff00;
531 if (!level_type)
532 break;
533 do_cpuid_1_ent(&entry[i], function, i);
534 entry[i].flags |=
535 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
536 ++*nent;
537 }
538 break;
539 }
540 case 0xd: {
541 int idx, i;
542 u64 supported = kvm_supported_xcr0();
543
544 entry->eax &= supported;
545 entry->ebx = xstate_required_size(supported, false);
546 entry->ecx = entry->ebx;
547 entry->edx &= supported >> 32;
548 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
549 if (!supported)
550 break;
551
552 for (idx = 1, i = 1; idx < 64; ++idx) {
553 u64 mask = ((u64)1 << idx);
554 if (*nent >= maxnent)
555 goto out;
556
557 do_cpuid_1_ent(&entry[i], function, idx);
558 if (idx == 1) {
559 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
560 cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
561 entry[i].ebx = 0;
562 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
563 entry[i].ebx =
564 xstate_required_size(supported,
565 true);
566 } else {
567 if (entry[i].eax == 0 || !(supported & mask))
568 continue;
569 if (WARN_ON_ONCE(entry[i].ecx & 1))
570 continue;
571 }
572 entry[i].ecx = 0;
573 entry[i].edx = 0;
574 entry[i].flags |=
575 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
576 ++*nent;
577 ++i;
578 }
579 break;
580 }
581 case KVM_CPUID_SIGNATURE: {
582 static const char signature[12] = "KVMKVMKVM\0\0";
583 const u32 *sigptr = (const u32 *)signature;
584 entry->eax = KVM_CPUID_FEATURES;
585 entry->ebx = sigptr[0];
586 entry->ecx = sigptr[1];
587 entry->edx = sigptr[2];
588 break;
589 }
590 case KVM_CPUID_FEATURES:
591 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
592 (1 << KVM_FEATURE_NOP_IO_DELAY) |
593 (1 << KVM_FEATURE_CLOCKSOURCE2) |
594 (1 << KVM_FEATURE_ASYNC_PF) |
595 (1 << KVM_FEATURE_PV_EOI) |
596 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
597 (1 << KVM_FEATURE_PV_UNHALT);
598
599 if (sched_info_on())
600 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
601
602 entry->ebx = 0;
603 entry->ecx = 0;
604 entry->edx = 0;
605 break;
606 case 0x80000000:
607 entry->eax = min(entry->eax, 0x8000001a);
608 break;
609 case 0x80000001:
610 entry->edx &= kvm_cpuid_8000_0001_edx_x86_features;
611 cpuid_mask(&entry->edx, CPUID_8000_0001_EDX);
612 entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features;
613 cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX);
614 break;
615 case 0x80000007: /* Advanced power management */
616 /* invariant TSC is CPUID.80000007H:EDX[8] */
617 entry->edx &= (1 << 8);
618 /* mask against host */
619 entry->edx &= boot_cpu_data.x86_power;
620 entry->eax = entry->ebx = entry->ecx = 0;
621 break;
622 case 0x80000008: {
623 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
624 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
625 unsigned phys_as = entry->eax & 0xff;
626
627 if (!g_phys_as)
628 g_phys_as = phys_as;
629 entry->eax = g_phys_as | (virt_as << 8);
630 entry->ebx = entry->edx = 0;
631 break;
632 }
633 case 0x80000019:
634 entry->ecx = entry->edx = 0;
635 break;
636 case 0x8000001a:
637 break;
638 case 0x8000001d:
639 break;
640 /*Add support for Centaur's CPUID instruction*/
641 case 0xC0000000:
642 /*Just support up to 0xC0000004 now*/
643 entry->eax = min(entry->eax, 0xC0000004);
644 break;
645 case 0xC0000001:
646 entry->edx &= kvm_cpuid_C000_0001_edx_x86_features;
647 cpuid_mask(&entry->edx, CPUID_C000_0001_EDX);
648 break;
649 case 3: /* Processor serial number */
650 case 5: /* MONITOR/MWAIT */
651 case 0xC0000002:
652 case 0xC0000003:
653 case 0xC0000004:
654 default:
655 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
656 break;
657 }
658
659 kvm_x86_ops->set_supported_cpuid(function, entry);
660
661 r = 0;
662
663 out:
664 put_cpu();
665
666 return r;
667 }
668
669 static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
670 u32 idx, int *nent, int maxnent, unsigned int type)
671 {
672 if (type == KVM_GET_EMULATED_CPUID)
673 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
674
675 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
676 }
677
678 #undef F
679
680 struct kvm_cpuid_param {
681 u32 func;
682 u32 idx;
683 bool has_leaf_count;
684 bool (*qualifier)(const struct kvm_cpuid_param *param);
685 };
686
687 static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
688 {
689 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
690 }
691
692 static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
693 __u32 num_entries, unsigned int ioctl_type)
694 {
695 int i;
696 __u32 pad[3];
697
698 if (ioctl_type != KVM_GET_EMULATED_CPUID)
699 return false;
700
701 /*
702 * We want to make sure that ->padding is being passed clean from
703 * userspace in case we want to use it for something in the future.
704 *
705 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
706 * have to give ourselves satisfied only with the emulated side. /me
707 * sheds a tear.
708 */
709 for (i = 0; i < num_entries; i++) {
710 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
711 return true;
712
713 if (pad[0] || pad[1] || pad[2])
714 return true;
715 }
716 return false;
717 }
718
719 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
720 struct kvm_cpuid_entry2 __user *entries,
721 unsigned int type)
722 {
723 struct kvm_cpuid_entry2 *cpuid_entries;
724 int limit, nent = 0, r = -E2BIG, i;
725 u32 func;
726 static const struct kvm_cpuid_param param[] = {
727 { .func = 0, .has_leaf_count = true },
728 { .func = 0x80000000, .has_leaf_count = true },
729 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
730 { .func = KVM_CPUID_SIGNATURE },
731 { .func = KVM_CPUID_FEATURES },
732 };
733
734 if (cpuid->nent < 1)
735 goto out;
736 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
737 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
738
739 if (sanity_check_entries(entries, cpuid->nent, type))
740 return -EINVAL;
741
742 r = -ENOMEM;
743 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
744 if (!cpuid_entries)
745 goto out;
746
747 r = 0;
748 for (i = 0; i < ARRAY_SIZE(param); i++) {
749 const struct kvm_cpuid_param *ent = &param[i];
750
751 if (ent->qualifier && !ent->qualifier(ent))
752 continue;
753
754 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
755 &nent, cpuid->nent, type);
756
757 if (r)
758 goto out_free;
759
760 if (!ent->has_leaf_count)
761 continue;
762
763 limit = cpuid_entries[nent - 1].eax;
764 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
765 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
766 &nent, cpuid->nent, type);
767
768 if (r)
769 goto out_free;
770 }
771
772 r = -EFAULT;
773 if (copy_to_user(entries, cpuid_entries,
774 nent * sizeof(struct kvm_cpuid_entry2)))
775 goto out_free;
776 cpuid->nent = nent;
777 r = 0;
778
779 out_free:
780 vfree(cpuid_entries);
781 out:
782 return r;
783 }
784
785 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
786 {
787 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
788 struct kvm_cpuid_entry2 *ej;
789 int j = i;
790 int nent = vcpu->arch.cpuid_nent;
791
792 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
793 /* when no next entry is found, the current entry[i] is reselected */
794 do {
795 j = (j + 1) % nent;
796 ej = &vcpu->arch.cpuid_entries[j];
797 } while (ej->function != e->function);
798
799 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
800
801 return j;
802 }
803
804 /* find an entry with matching function, matching index (if needed), and that
805 * should be read next (if it's stateful) */
806 static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
807 u32 function, u32 index)
808 {
809 if (e->function != function)
810 return 0;
811 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
812 return 0;
813 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
814 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
815 return 0;
816 return 1;
817 }
818
819 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
820 u32 function, u32 index)
821 {
822 int i;
823 struct kvm_cpuid_entry2 *best = NULL;
824
825 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
826 struct kvm_cpuid_entry2 *e;
827
828 e = &vcpu->arch.cpuid_entries[i];
829 if (is_matching_cpuid_entry(e, function, index)) {
830 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
831 move_to_next_stateful_cpuid_entry(vcpu, i);
832 best = e;
833 break;
834 }
835 }
836 return best;
837 }
838 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
839
840 /*
841 * If no match is found, check whether we exceed the vCPU's limit
842 * and return the content of the highest valid _standard_ leaf instead.
843 * This is to satisfy the CPUID specification.
844 */
845 static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
846 u32 function, u32 index)
847 {
848 struct kvm_cpuid_entry2 *maxlevel;
849
850 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
851 if (!maxlevel || maxlevel->eax >= function)
852 return NULL;
853 if (function & 0x80000000) {
854 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
855 if (!maxlevel)
856 return NULL;
857 }
858 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
859 }
860
861 bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
862 u32 *ecx, u32 *edx, bool check_limit)
863 {
864 u32 function = *eax, index = *ecx;
865 struct kvm_cpuid_entry2 *best;
866 bool entry_found = true;
867
868 best = kvm_find_cpuid_entry(vcpu, function, index);
869
870 if (!best) {
871 entry_found = false;
872 if (!check_limit)
873 goto out;
874
875 best = check_cpuid_limit(vcpu, function, index);
876 }
877
878 out:
879 if (best) {
880 *eax = best->eax;
881 *ebx = best->ebx;
882 *ecx = best->ecx;
883 *edx = best->edx;
884 } else
885 *eax = *ebx = *ecx = *edx = 0;
886 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, entry_found);
887 return entry_found;
888 }
889 EXPORT_SYMBOL_GPL(kvm_cpuid);
890
891 int kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
892 {
893 u32 eax, ebx, ecx, edx;
894
895 if (cpuid_fault_enabled(vcpu) && !kvm_require_cpl(vcpu, 0))
896 return 1;
897
898 eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
899 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
900 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx, true);
901 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
902 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
903 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
904 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
905 return kvm_skip_emulated_instruction(vcpu);
906 }
907 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
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