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Merge tag 'nfsd-4.6' of git://linux-nfs.org/~bfields/linux
[mirror_ubuntu-zesty-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/module.h>
17 #include <linux/vmalloc.h>
18 #include <linux/uaccess.h>
19 #include <asm/fpu/internal.h> /* For use_eager_fpu. Ugh! */
20 #include <asm/user.h>
21 #include <asm/fpu/xstate.h>
22 #include "cpuid.h"
23 #include "lapic.h"
24 #include "mmu.h"
25 #include "trace.h"
26 #include "pmu.h"
27
28 static u32 xstate_required_size(u64 xstate_bv, bool compacted)
29 {
30 int feature_bit = 0;
31 u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
32
33 xstate_bv &= XFEATURE_MASK_EXTEND;
34 while (xstate_bv) {
35 if (xstate_bv & 0x1) {
36 u32 eax, ebx, ecx, edx, offset;
37 cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx);
38 offset = compacted ? ret : ebx;
39 ret = max(ret, offset + eax);
40 }
41
42 xstate_bv >>= 1;
43 feature_bit++;
44 }
45
46 return ret;
47 }
48
49 bool kvm_mpx_supported(void)
50 {
51 return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
52 && kvm_x86_ops->mpx_supported());
53 }
54 EXPORT_SYMBOL_GPL(kvm_mpx_supported);
55
56 u64 kvm_supported_xcr0(void)
57 {
58 u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
59
60 if (!kvm_mpx_supported())
61 xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
62
63 return xcr0;
64 }
65
66 #define F(x) bit(X86_FEATURE_##x)
67
68 int kvm_update_cpuid(struct kvm_vcpu *vcpu)
69 {
70 struct kvm_cpuid_entry2 *best;
71 struct kvm_lapic *apic = vcpu->arch.apic;
72
73 best = kvm_find_cpuid_entry(vcpu, 1, 0);
74 if (!best)
75 return 0;
76
77 /* Update OSXSAVE bit */
78 if (cpu_has_xsave && best->function == 0x1) {
79 best->ecx &= ~F(OSXSAVE);
80 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
81 best->ecx |= F(OSXSAVE);
82 }
83
84 if (apic) {
85 if (best->ecx & F(TSC_DEADLINE_TIMER))
86 apic->lapic_timer.timer_mode_mask = 3 << 17;
87 else
88 apic->lapic_timer.timer_mode_mask = 1 << 17;
89 }
90
91 best = kvm_find_cpuid_entry(vcpu, 7, 0);
92 if (best) {
93 /* Update OSPKE bit */
94 if (boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) {
95 best->ecx &= ~F(OSPKE);
96 if (kvm_read_cr4_bits(vcpu, X86_CR4_PKE))
97 best->ecx |= F(OSPKE);
98 }
99 }
100
101 best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
102 if (!best) {
103 vcpu->arch.guest_supported_xcr0 = 0;
104 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
105 } else {
106 vcpu->arch.guest_supported_xcr0 =
107 (best->eax | ((u64)best->edx << 32)) &
108 kvm_supported_xcr0();
109 vcpu->arch.guest_xstate_size = best->ebx =
110 xstate_required_size(vcpu->arch.xcr0, false);
111 }
112
113 best = kvm_find_cpuid_entry(vcpu, 0xD, 1);
114 if (best && (best->eax & (F(XSAVES) | F(XSAVEC))))
115 best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
116
117 if (use_eager_fpu())
118 kvm_x86_ops->fpu_activate(vcpu);
119
120 /*
121 * The existing code assumes virtual address is 48-bit in the canonical
122 * address checks; exit if it is ever changed.
123 */
124 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
125 if (best && ((best->eax & 0xff00) >> 8) != 48 &&
126 ((best->eax & 0xff00) >> 8) != 0)
127 return -EINVAL;
128
129 /* Update physical-address width */
130 vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
131
132 kvm_pmu_refresh(vcpu);
133 return 0;
134 }
135
136 static int is_efer_nx(void)
137 {
138 unsigned long long efer = 0;
139
140 rdmsrl_safe(MSR_EFER, &efer);
141 return efer & EFER_NX;
142 }
143
144 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
145 {
146 int i;
147 struct kvm_cpuid_entry2 *e, *entry;
148
149 entry = NULL;
150 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
151 e = &vcpu->arch.cpuid_entries[i];
152 if (e->function == 0x80000001) {
153 entry = e;
154 break;
155 }
156 }
157 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
158 entry->edx &= ~F(NX);
159 printk(KERN_INFO "kvm: guest NX capability removed\n");
160 }
161 }
162
163 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
164 {
165 struct kvm_cpuid_entry2 *best;
166
167 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
168 if (!best || best->eax < 0x80000008)
169 goto not_found;
170 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
171 if (best)
172 return best->eax & 0xff;
173 not_found:
174 return 36;
175 }
176 EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
177
178 /* when an old userspace process fills a new kernel module */
179 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
180 struct kvm_cpuid *cpuid,
181 struct kvm_cpuid_entry __user *entries)
182 {
183 int r, i;
184 struct kvm_cpuid_entry *cpuid_entries;
185
186 r = -E2BIG;
187 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
188 goto out;
189 r = -ENOMEM;
190 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) * cpuid->nent);
191 if (!cpuid_entries)
192 goto out;
193 r = -EFAULT;
194 if (copy_from_user(cpuid_entries, entries,
195 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
196 goto out_free;
197 for (i = 0; i < cpuid->nent; i++) {
198 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
199 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
200 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
201 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
202 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
203 vcpu->arch.cpuid_entries[i].index = 0;
204 vcpu->arch.cpuid_entries[i].flags = 0;
205 vcpu->arch.cpuid_entries[i].padding[0] = 0;
206 vcpu->arch.cpuid_entries[i].padding[1] = 0;
207 vcpu->arch.cpuid_entries[i].padding[2] = 0;
208 }
209 vcpu->arch.cpuid_nent = cpuid->nent;
210 cpuid_fix_nx_cap(vcpu);
211 kvm_apic_set_version(vcpu);
212 kvm_x86_ops->cpuid_update(vcpu);
213 r = kvm_update_cpuid(vcpu);
214
215 out_free:
216 vfree(cpuid_entries);
217 out:
218 return r;
219 }
220
221 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
222 struct kvm_cpuid2 *cpuid,
223 struct kvm_cpuid_entry2 __user *entries)
224 {
225 int r;
226
227 r = -E2BIG;
228 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
229 goto out;
230 r = -EFAULT;
231 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
232 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
233 goto out;
234 vcpu->arch.cpuid_nent = cpuid->nent;
235 kvm_apic_set_version(vcpu);
236 kvm_x86_ops->cpuid_update(vcpu);
237 r = kvm_update_cpuid(vcpu);
238 out:
239 return r;
240 }
241
242 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
243 struct kvm_cpuid2 *cpuid,
244 struct kvm_cpuid_entry2 __user *entries)
245 {
246 int r;
247
248 r = -E2BIG;
249 if (cpuid->nent < vcpu->arch.cpuid_nent)
250 goto out;
251 r = -EFAULT;
252 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
253 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
254 goto out;
255 return 0;
256
257 out:
258 cpuid->nent = vcpu->arch.cpuid_nent;
259 return r;
260 }
261
262 static void cpuid_mask(u32 *word, int wordnum)
263 {
264 *word &= boot_cpu_data.x86_capability[wordnum];
265 }
266
267 static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
268 u32 index)
269 {
270 entry->function = function;
271 entry->index = index;
272 cpuid_count(entry->function, entry->index,
273 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
274 entry->flags = 0;
275 }
276
277 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
278 u32 func, u32 index, int *nent, int maxnent)
279 {
280 switch (func) {
281 case 0:
282 entry->eax = 1; /* only one leaf currently */
283 ++*nent;
284 break;
285 case 1:
286 entry->ecx = F(MOVBE);
287 ++*nent;
288 break;
289 default:
290 break;
291 }
292
293 entry->function = func;
294 entry->index = index;
295
296 return 0;
297 }
298
299 static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
300 u32 index, int *nent, int maxnent)
301 {
302 int r;
303 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
304 #ifdef CONFIG_X86_64
305 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
306 ? F(GBPAGES) : 0;
307 unsigned f_lm = F(LM);
308 #else
309 unsigned f_gbpages = 0;
310 unsigned f_lm = 0;
311 #endif
312 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
313 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
314 unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
315 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
316
317 /* cpuid 1.edx */
318 const u32 kvm_cpuid_1_edx_x86_features =
319 F(FPU) | F(VME) | F(DE) | F(PSE) |
320 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
321 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
322 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
323 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
324 0 /* Reserved, DS, ACPI */ | F(MMX) |
325 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
326 0 /* HTT, TM, Reserved, PBE */;
327 /* cpuid 0x80000001.edx */
328 const u32 kvm_cpuid_8000_0001_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(SYSCALL) |
332 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
333 F(PAT) | F(PSE36) | 0 /* Reserved */ |
334 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
335 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
336 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
337 /* cpuid 1.ecx */
338 const u32 kvm_cpuid_1_ecx_x86_features =
339 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
340 * but *not* advertised to guests via CPUID ! */
341 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
342 0 /* DS-CPL, VMX, SMX, EST */ |
343 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
344 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
345 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
346 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
347 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
348 F(F16C) | F(RDRAND);
349 /* cpuid 0x80000001.ecx */
350 const u32 kvm_cpuid_8000_0001_ecx_x86_features =
351 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
352 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
353 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
354 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
355
356 /* cpuid 0xC0000001.edx */
357 const u32 kvm_cpuid_C000_0001_edx_x86_features =
358 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
359 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
360 F(PMM) | F(PMM_EN);
361
362 /* cpuid 7.0.ebx */
363 const u32 kvm_cpuid_7_0_ebx_x86_features =
364 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
365 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
366 F(ADX) | F(SMAP) | F(AVX512F) | F(AVX512PF) | F(AVX512ER) |
367 F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(PCOMMIT);
368
369 /* cpuid 0xD.1.eax */
370 const u32 kvm_cpuid_D_1_eax_x86_features =
371 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
372
373 /* cpuid 7.0.ecx*/
374 const u32 kvm_cpuid_7_0_ecx_x86_features = F(PKU) | 0 /*OSPKE*/;
375
376 /* all calls to cpuid_count() should be made on the same cpu */
377 get_cpu();
378
379 r = -E2BIG;
380
381 if (*nent >= maxnent)
382 goto out;
383
384 do_cpuid_1_ent(entry, function, index);
385 ++*nent;
386
387 switch (function) {
388 case 0:
389 entry->eax = min(entry->eax, (u32)0xd);
390 break;
391 case 1:
392 entry->edx &= kvm_cpuid_1_edx_x86_features;
393 cpuid_mask(&entry->edx, CPUID_1_EDX);
394 entry->ecx &= kvm_cpuid_1_ecx_x86_features;
395 cpuid_mask(&entry->ecx, CPUID_1_ECX);
396 /* we support x2apic emulation even if host does not support
397 * it since we emulate x2apic in software */
398 entry->ecx |= F(X2APIC);
399 break;
400 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
401 * may return different values. This forces us to get_cpu() before
402 * issuing the first command, and also to emulate this annoying behavior
403 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
404 case 2: {
405 int t, times = entry->eax & 0xff;
406
407 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
408 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
409 for (t = 1; t < times; ++t) {
410 if (*nent >= maxnent)
411 goto out;
412
413 do_cpuid_1_ent(&entry[t], function, 0);
414 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
415 ++*nent;
416 }
417 break;
418 }
419 /* function 4 has additional index. */
420 case 4: {
421 int i, cache_type;
422
423 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
424 /* read more entries until cache_type is zero */
425 for (i = 1; ; ++i) {
426 if (*nent >= maxnent)
427 goto out;
428
429 cache_type = entry[i - 1].eax & 0x1f;
430 if (!cache_type)
431 break;
432 do_cpuid_1_ent(&entry[i], function, i);
433 entry[i].flags |=
434 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
435 ++*nent;
436 }
437 break;
438 }
439 case 6: /* Thermal management */
440 entry->eax = 0x4; /* allow ARAT */
441 entry->ebx = 0;
442 entry->ecx = 0;
443 entry->edx = 0;
444 break;
445 case 7: {
446 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
447 /* Mask ebx against host capability word 9 */
448 if (index == 0) {
449 entry->ebx &= kvm_cpuid_7_0_ebx_x86_features;
450 cpuid_mask(&entry->ebx, CPUID_7_0_EBX);
451 // TSC_ADJUST is emulated
452 entry->ebx |= F(TSC_ADJUST);
453 entry->ecx &= kvm_cpuid_7_0_ecx_x86_features;
454 cpuid_mask(&entry->ecx, CPUID_7_ECX);
455 /* PKU is not yet implemented for shadow paging. */
456 if (!tdp_enabled)
457 entry->ecx &= ~F(PKU);
458 } else {
459 entry->ebx = 0;
460 entry->ecx = 0;
461 }
462 entry->eax = 0;
463 entry->edx = 0;
464 break;
465 }
466 case 9:
467 break;
468 case 0xa: { /* Architectural Performance Monitoring */
469 struct x86_pmu_capability cap;
470 union cpuid10_eax eax;
471 union cpuid10_edx edx;
472
473 perf_get_x86_pmu_capability(&cap);
474
475 /*
476 * Only support guest architectural pmu on a host
477 * with architectural pmu.
478 */
479 if (!cap.version)
480 memset(&cap, 0, sizeof(cap));
481
482 eax.split.version_id = min(cap.version, 2);
483 eax.split.num_counters = cap.num_counters_gp;
484 eax.split.bit_width = cap.bit_width_gp;
485 eax.split.mask_length = cap.events_mask_len;
486
487 edx.split.num_counters_fixed = cap.num_counters_fixed;
488 edx.split.bit_width_fixed = cap.bit_width_fixed;
489 edx.split.reserved = 0;
490
491 entry->eax = eax.full;
492 entry->ebx = cap.events_mask;
493 entry->ecx = 0;
494 entry->edx = edx.full;
495 break;
496 }
497 /* function 0xb has additional index. */
498 case 0xb: {
499 int i, level_type;
500
501 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
502 /* read more entries until level_type is zero */
503 for (i = 1; ; ++i) {
504 if (*nent >= maxnent)
505 goto out;
506
507 level_type = entry[i - 1].ecx & 0xff00;
508 if (!level_type)
509 break;
510 do_cpuid_1_ent(&entry[i], function, i);
511 entry[i].flags |=
512 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
513 ++*nent;
514 }
515 break;
516 }
517 case 0xd: {
518 int idx, i;
519 u64 supported = kvm_supported_xcr0();
520
521 entry->eax &= supported;
522 entry->ebx = xstate_required_size(supported, false);
523 entry->ecx = entry->ebx;
524 entry->edx &= supported >> 32;
525 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
526 if (!supported)
527 break;
528
529 for (idx = 1, i = 1; idx < 64; ++idx) {
530 u64 mask = ((u64)1 << idx);
531 if (*nent >= maxnent)
532 goto out;
533
534 do_cpuid_1_ent(&entry[i], function, idx);
535 if (idx == 1) {
536 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
537 entry[i].ebx = 0;
538 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
539 entry[i].ebx =
540 xstate_required_size(supported,
541 true);
542 } else {
543 if (entry[i].eax == 0 || !(supported & mask))
544 continue;
545 if (WARN_ON_ONCE(entry[i].ecx & 1))
546 continue;
547 }
548 entry[i].ecx = 0;
549 entry[i].edx = 0;
550 entry[i].flags |=
551 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
552 ++*nent;
553 ++i;
554 }
555 break;
556 }
557 case KVM_CPUID_SIGNATURE: {
558 static const char signature[12] = "KVMKVMKVM\0\0";
559 const u32 *sigptr = (const u32 *)signature;
560 entry->eax = KVM_CPUID_FEATURES;
561 entry->ebx = sigptr[0];
562 entry->ecx = sigptr[1];
563 entry->edx = sigptr[2];
564 break;
565 }
566 case KVM_CPUID_FEATURES:
567 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
568 (1 << KVM_FEATURE_NOP_IO_DELAY) |
569 (1 << KVM_FEATURE_CLOCKSOURCE2) |
570 (1 << KVM_FEATURE_ASYNC_PF) |
571 (1 << KVM_FEATURE_PV_EOI) |
572 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
573 (1 << KVM_FEATURE_PV_UNHALT);
574
575 if (sched_info_on())
576 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
577
578 entry->ebx = 0;
579 entry->ecx = 0;
580 entry->edx = 0;
581 break;
582 case 0x80000000:
583 entry->eax = min(entry->eax, 0x8000001a);
584 break;
585 case 0x80000001:
586 entry->edx &= kvm_cpuid_8000_0001_edx_x86_features;
587 cpuid_mask(&entry->edx, CPUID_8000_0001_EDX);
588 entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features;
589 cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX);
590 break;
591 case 0x80000007: /* Advanced power management */
592 /* invariant TSC is CPUID.80000007H:EDX[8] */
593 entry->edx &= (1 << 8);
594 /* mask against host */
595 entry->edx &= boot_cpu_data.x86_power;
596 entry->eax = entry->ebx = entry->ecx = 0;
597 break;
598 case 0x80000008: {
599 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
600 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
601 unsigned phys_as = entry->eax & 0xff;
602
603 if (!g_phys_as)
604 g_phys_as = phys_as;
605 entry->eax = g_phys_as | (virt_as << 8);
606 entry->ebx = entry->edx = 0;
607 break;
608 }
609 case 0x80000019:
610 entry->ecx = entry->edx = 0;
611 break;
612 case 0x8000001a:
613 break;
614 case 0x8000001d:
615 break;
616 /*Add support for Centaur's CPUID instruction*/
617 case 0xC0000000:
618 /*Just support up to 0xC0000004 now*/
619 entry->eax = min(entry->eax, 0xC0000004);
620 break;
621 case 0xC0000001:
622 entry->edx &= kvm_cpuid_C000_0001_edx_x86_features;
623 cpuid_mask(&entry->edx, CPUID_C000_0001_EDX);
624 break;
625 case 3: /* Processor serial number */
626 case 5: /* MONITOR/MWAIT */
627 case 0xC0000002:
628 case 0xC0000003:
629 case 0xC0000004:
630 default:
631 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
632 break;
633 }
634
635 kvm_x86_ops->set_supported_cpuid(function, entry);
636
637 r = 0;
638
639 out:
640 put_cpu();
641
642 return r;
643 }
644
645 static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
646 u32 idx, int *nent, int maxnent, unsigned int type)
647 {
648 if (type == KVM_GET_EMULATED_CPUID)
649 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
650
651 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
652 }
653
654 #undef F
655
656 struct kvm_cpuid_param {
657 u32 func;
658 u32 idx;
659 bool has_leaf_count;
660 bool (*qualifier)(const struct kvm_cpuid_param *param);
661 };
662
663 static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
664 {
665 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
666 }
667
668 static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
669 __u32 num_entries, unsigned int ioctl_type)
670 {
671 int i;
672 __u32 pad[3];
673
674 if (ioctl_type != KVM_GET_EMULATED_CPUID)
675 return false;
676
677 /*
678 * We want to make sure that ->padding is being passed clean from
679 * userspace in case we want to use it for something in the future.
680 *
681 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
682 * have to give ourselves satisfied only with the emulated side. /me
683 * sheds a tear.
684 */
685 for (i = 0; i < num_entries; i++) {
686 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
687 return true;
688
689 if (pad[0] || pad[1] || pad[2])
690 return true;
691 }
692 return false;
693 }
694
695 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
696 struct kvm_cpuid_entry2 __user *entries,
697 unsigned int type)
698 {
699 struct kvm_cpuid_entry2 *cpuid_entries;
700 int limit, nent = 0, r = -E2BIG, i;
701 u32 func;
702 static const struct kvm_cpuid_param param[] = {
703 { .func = 0, .has_leaf_count = true },
704 { .func = 0x80000000, .has_leaf_count = true },
705 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
706 { .func = KVM_CPUID_SIGNATURE },
707 { .func = KVM_CPUID_FEATURES },
708 };
709
710 if (cpuid->nent < 1)
711 goto out;
712 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
713 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
714
715 if (sanity_check_entries(entries, cpuid->nent, type))
716 return -EINVAL;
717
718 r = -ENOMEM;
719 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
720 if (!cpuid_entries)
721 goto out;
722
723 r = 0;
724 for (i = 0; i < ARRAY_SIZE(param); i++) {
725 const struct kvm_cpuid_param *ent = &param[i];
726
727 if (ent->qualifier && !ent->qualifier(ent))
728 continue;
729
730 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
731 &nent, cpuid->nent, type);
732
733 if (r)
734 goto out_free;
735
736 if (!ent->has_leaf_count)
737 continue;
738
739 limit = cpuid_entries[nent - 1].eax;
740 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
741 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
742 &nent, cpuid->nent, type);
743
744 if (r)
745 goto out_free;
746 }
747
748 r = -EFAULT;
749 if (copy_to_user(entries, cpuid_entries,
750 nent * sizeof(struct kvm_cpuid_entry2)))
751 goto out_free;
752 cpuid->nent = nent;
753 r = 0;
754
755 out_free:
756 vfree(cpuid_entries);
757 out:
758 return r;
759 }
760
761 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
762 {
763 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
764 int j, nent = vcpu->arch.cpuid_nent;
765
766 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
767 /* when no next entry is found, the current entry[i] is reselected */
768 for (j = i + 1; ; j = (j + 1) % nent) {
769 struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j];
770 if (ej->function == e->function) {
771 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
772 return j;
773 }
774 }
775 return 0; /* silence gcc, even though control never reaches here */
776 }
777
778 /* find an entry with matching function, matching index (if needed), and that
779 * should be read next (if it's stateful) */
780 static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
781 u32 function, u32 index)
782 {
783 if (e->function != function)
784 return 0;
785 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
786 return 0;
787 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
788 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
789 return 0;
790 return 1;
791 }
792
793 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
794 u32 function, u32 index)
795 {
796 int i;
797 struct kvm_cpuid_entry2 *best = NULL;
798
799 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
800 struct kvm_cpuid_entry2 *e;
801
802 e = &vcpu->arch.cpuid_entries[i];
803 if (is_matching_cpuid_entry(e, function, index)) {
804 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
805 move_to_next_stateful_cpuid_entry(vcpu, i);
806 best = e;
807 break;
808 }
809 }
810 return best;
811 }
812 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
813
814 /*
815 * If no match is found, check whether we exceed the vCPU's limit
816 * and return the content of the highest valid _standard_ leaf instead.
817 * This is to satisfy the CPUID specification.
818 */
819 static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
820 u32 function, u32 index)
821 {
822 struct kvm_cpuid_entry2 *maxlevel;
823
824 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
825 if (!maxlevel || maxlevel->eax >= function)
826 return NULL;
827 if (function & 0x80000000) {
828 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
829 if (!maxlevel)
830 return NULL;
831 }
832 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
833 }
834
835 void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
836 {
837 u32 function = *eax, index = *ecx;
838 struct kvm_cpuid_entry2 *best;
839
840 best = kvm_find_cpuid_entry(vcpu, function, index);
841
842 if (!best)
843 best = check_cpuid_limit(vcpu, function, index);
844
845 /*
846 * Perfmon not yet supported for L2 guest.
847 */
848 if (is_guest_mode(vcpu) && function == 0xa)
849 best = NULL;
850
851 if (best) {
852 *eax = best->eax;
853 *ebx = best->ebx;
854 *ecx = best->ecx;
855 *edx = best->edx;
856 } else
857 *eax = *ebx = *ecx = *edx = 0;
858 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx);
859 }
860 EXPORT_SYMBOL_GPL(kvm_cpuid);
861
862 void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
863 {
864 u32 function, eax, ebx, ecx, edx;
865
866 function = eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
867 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
868 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx);
869 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
870 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
871 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
872 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
873 kvm_x86_ops->skip_emulated_instruction(vcpu);
874 }
875 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
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