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KVM: x86: add support for UMIP
[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kvm / cpuid.c
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CommitLineData
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
30static 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
51bool kvm_mpx_supported(void)
52{
53 return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
54 && kvm_x86_ops->mpx_supported());
55}
56EXPORT_SYMBOL_GPL(kvm_mpx_supported);
57
58u64 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/* For scattered features from cpufeatures.h; we currently expose none */
71#define KF(x) bit(KVM_CPUID_BIT_##x)
72
73int kvm_update_cpuid(struct kvm_vcpu *vcpu)
74{
75 struct kvm_cpuid_entry2 *best;
76 struct kvm_lapic *apic = vcpu->arch.apic;
77
78 best = kvm_find_cpuid_entry(vcpu, 1, 0);
79 if (!best)
80 return 0;
81
82 /* Update OSXSAVE bit */
83 if (boot_cpu_has(X86_FEATURE_XSAVE) && best->function == 0x1) {
84 best->ecx &= ~F(OSXSAVE);
85 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
86 best->ecx |= F(OSXSAVE);
87 }
88
89 best->edx &= ~F(APIC);
90 if (vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE)
91 best->edx |= F(APIC);
92
93 if (apic) {
94 if (best->ecx & F(TSC_DEADLINE_TIMER))
95 apic->lapic_timer.timer_mode_mask = 3 << 17;
96 else
97 apic->lapic_timer.timer_mode_mask = 1 << 17;
98 }
99
100 best = kvm_find_cpuid_entry(vcpu, 7, 0);
101 if (best) {
102 /* Update OSPKE bit */
103 if (boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) {
104 best->ecx &= ~F(OSPKE);
105 if (kvm_read_cr4_bits(vcpu, X86_CR4_PKE))
106 best->ecx |= F(OSPKE);
107 }
108 }
109
110 best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
111 if (!best) {
112 vcpu->arch.guest_supported_xcr0 = 0;
113 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
114 } else {
115 vcpu->arch.guest_supported_xcr0 =
116 (best->eax | ((u64)best->edx << 32)) &
117 kvm_supported_xcr0();
118 vcpu->arch.guest_xstate_size = best->ebx =
119 xstate_required_size(vcpu->arch.xcr0, false);
120 }
121
122 best = kvm_find_cpuid_entry(vcpu, 0xD, 1);
123 if (best && (best->eax & (F(XSAVES) | F(XSAVEC))))
124 best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
125
126 /*
127 * The existing code assumes virtual address is 48-bit or 57-bit in the
128 * canonical address checks; exit if it is ever changed.
129 */
130 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
131 if (best) {
132 int vaddr_bits = (best->eax & 0xff00) >> 8;
133
134 if (vaddr_bits != 48 && vaddr_bits != 57 && vaddr_bits != 0)
135 return -EINVAL;
136 }
137
138 /* Update physical-address width */
139 vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
140 kvm_mmu_reset_context(vcpu);
141
142 kvm_pmu_refresh(vcpu);
143 return 0;
144}
145
146static int is_efer_nx(void)
147{
148 unsigned long long efer = 0;
149
150 rdmsrl_safe(MSR_EFER, &efer);
151 return efer & EFER_NX;
152}
153
154static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
155{
156 int i;
157 struct kvm_cpuid_entry2 *e, *entry;
158
159 entry = NULL;
160 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
161 e = &vcpu->arch.cpuid_entries[i];
162 if (e->function == 0x80000001) {
163 entry = e;
164 break;
165 }
166 }
167 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
168 entry->edx &= ~F(NX);
169 printk(KERN_INFO "kvm: guest NX capability removed\n");
170 }
171}
172
173int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
174{
175 struct kvm_cpuid_entry2 *best;
176
177 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
178 if (!best || best->eax < 0x80000008)
179 goto not_found;
180 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
181 if (best)
182 return best->eax & 0xff;
183not_found:
184 return 36;
185}
186EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
187
188/* when an old userspace process fills a new kernel module */
189int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
190 struct kvm_cpuid *cpuid,
191 struct kvm_cpuid_entry __user *entries)
192{
193 int r, i;
194 struct kvm_cpuid_entry *cpuid_entries = NULL;
195
196 r = -E2BIG;
197 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
198 goto out;
199 r = -ENOMEM;
200 if (cpuid->nent) {
201 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) *
202 cpuid->nent);
203 if (!cpuid_entries)
204 goto out;
205 r = -EFAULT;
206 if (copy_from_user(cpuid_entries, entries,
207 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
208 goto out;
209 }
210 for (i = 0; i < cpuid->nent; i++) {
211 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
212 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
213 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
214 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
215 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
216 vcpu->arch.cpuid_entries[i].index = 0;
217 vcpu->arch.cpuid_entries[i].flags = 0;
218 vcpu->arch.cpuid_entries[i].padding[0] = 0;
219 vcpu->arch.cpuid_entries[i].padding[1] = 0;
220 vcpu->arch.cpuid_entries[i].padding[2] = 0;
221 }
222 vcpu->arch.cpuid_nent = cpuid->nent;
223 cpuid_fix_nx_cap(vcpu);
224 kvm_apic_set_version(vcpu);
225 kvm_x86_ops->cpuid_update(vcpu);
226 r = kvm_update_cpuid(vcpu);
227
228out:
229 vfree(cpuid_entries);
230 return r;
231}
232
233int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
234 struct kvm_cpuid2 *cpuid,
235 struct kvm_cpuid_entry2 __user *entries)
236{
237 int r;
238
239 r = -E2BIG;
240 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
241 goto out;
242 r = -EFAULT;
243 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
244 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
245 goto out;
246 vcpu->arch.cpuid_nent = cpuid->nent;
247 kvm_apic_set_version(vcpu);
248 kvm_x86_ops->cpuid_update(vcpu);
249 r = kvm_update_cpuid(vcpu);
250out:
251 return r;
252}
253
254int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
255 struct kvm_cpuid2 *cpuid,
256 struct kvm_cpuid_entry2 __user *entries)
257{
258 int r;
259
260 r = -E2BIG;
261 if (cpuid->nent < vcpu->arch.cpuid_nent)
262 goto out;
263 r = -EFAULT;
264 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
265 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
266 goto out;
267 return 0;
268
269out:
270 cpuid->nent = vcpu->arch.cpuid_nent;
271 return r;
272}
273
274static void cpuid_mask(u32 *word, int wordnum)
275{
276 *word &= boot_cpu_data.x86_capability[wordnum];
277}
278
279static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
280 u32 index)
281{
282 entry->function = function;
283 entry->index = index;
284 cpuid_count(entry->function, entry->index,
285 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
286 entry->flags = 0;
287}
288
289static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
290 u32 func, u32 index, int *nent, int maxnent)
291{
292 switch (func) {
293 case 0:
294 entry->eax = 1; /* only one leaf currently */
295 ++*nent;
296 break;
297 case 1:
298 entry->ecx = F(MOVBE);
299 ++*nent;
300 break;
301 default:
302 break;
303 }
304
305 entry->function = func;
306 entry->index = index;
307
308 return 0;
309}
310
311static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
312 u32 index, int *nent, int maxnent)
313{
314 int r;
315 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
316#ifdef CONFIG_X86_64
317 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
318 ? F(GBPAGES) : 0;
319 unsigned f_lm = F(LM);
320#else
321 unsigned f_gbpages = 0;
322 unsigned f_lm = 0;
323#endif
324 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
325 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
326 unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
327 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
328
329 /* cpuid 1.edx */
330 const u32 kvm_cpuid_1_edx_x86_features =
331 F(FPU) | F(VME) | F(DE) | F(PSE) |
332 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
333 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
334 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
335 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
336 0 /* Reserved, DS, ACPI */ | F(MMX) |
337 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
338 0 /* HTT, TM, Reserved, PBE */;
339 /* cpuid 0x80000001.edx */
340 const u32 kvm_cpuid_8000_0001_edx_x86_features =
341 F(FPU) | F(VME) | F(DE) | F(PSE) |
342 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
343 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) |
344 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
345 F(PAT) | F(PSE36) | 0 /* Reserved */ |
346 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
347 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
348 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
349 /* cpuid 1.ecx */
350 const u32 kvm_cpuid_1_ecx_x86_features =
351 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
352 * but *not* advertised to guests via CPUID ! */
353 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
354 0 /* DS-CPL, VMX, SMX, EST */ |
355 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
356 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
357 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
358 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
359 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
360 F(F16C) | F(RDRAND);
361 /* cpuid 0x80000001.ecx */
362 const u32 kvm_cpuid_8000_0001_ecx_x86_features =
363 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
364 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
365 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
366 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
367
368 /* cpuid 0x80000008.ebx */
369 const u32 kvm_cpuid_8000_0008_ebx_x86_features =
370 F(IBPB) | F(IBRS);
371
372 /* cpuid 0xC0000001.edx */
373 const u32 kvm_cpuid_C000_0001_edx_x86_features =
374 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
375 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
376 F(PMM) | F(PMM_EN);
377
378 /* cpuid 7.0.ebx */
379 const u32 kvm_cpuid_7_0_ebx_x86_features =
380 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
381 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
382 F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) |
383 F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) |
384 F(SHA_NI) | F(AVX512BW) | F(AVX512VL);
385
386 /* cpuid 0xD.1.eax */
387 const u32 kvm_cpuid_D_1_eax_x86_features =
388 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
389
390 /* cpuid 7.0.ecx*/
391 const u32 kvm_cpuid_7_0_ecx_x86_features =
392 F(AVX512VBMI) | F(LA57) | F(PKU) | 0 /*OSPKE*/ |
393 F(AVX512_VPOPCNTDQ) | F(UMIP);
394
395 /* cpuid 7.0.edx*/
396 const u32 kvm_cpuid_7_0_edx_x86_features =
397 F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |
398 F(ARCH_CAPABILITIES);
399
400 /* all calls to cpuid_count() should be made on the same cpu */
401 get_cpu();
402
403 r = -E2BIG;
404
405 if (*nent >= maxnent)
406 goto out;
407
408 do_cpuid_1_ent(entry, function, index);
409 ++*nent;
410
411 switch (function) {
412 case 0:
413 entry->eax = min(entry->eax, (u32)0xd);
414 break;
415 case 1:
416 entry->edx &= kvm_cpuid_1_edx_x86_features;
417 cpuid_mask(&entry->edx, CPUID_1_EDX);
418 entry->ecx &= kvm_cpuid_1_ecx_x86_features;
419 cpuid_mask(&entry->ecx, CPUID_1_ECX);
420 /* we support x2apic emulation even if host does not support
421 * it since we emulate x2apic in software */
422 entry->ecx |= F(X2APIC);
423 break;
424 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
425 * may return different values. This forces us to get_cpu() before
426 * issuing the first command, and also to emulate this annoying behavior
427 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
428 case 2: {
429 int t, times = entry->eax & 0xff;
430
431 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
432 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
433 for (t = 1; t < times; ++t) {
434 if (*nent >= maxnent)
435 goto out;
436
437 do_cpuid_1_ent(&entry[t], function, 0);
438 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
439 ++*nent;
440 }
441 break;
442 }
443 /* function 4 has additional index. */
444 case 4: {
445 int i, cache_type;
446
447 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
448 /* read more entries until cache_type is zero */
449 for (i = 1; ; ++i) {
450 if (*nent >= maxnent)
451 goto out;
452
453 cache_type = entry[i - 1].eax & 0x1f;
454 if (!cache_type)
455 break;
456 do_cpuid_1_ent(&entry[i], function, i);
457 entry[i].flags |=
458 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
459 ++*nent;
460 }
461 break;
462 }
463 case 6: /* Thermal management */
464 entry->eax = 0x4; /* allow ARAT */
465 entry->ebx = 0;
466 entry->ecx = 0;
467 entry->edx = 0;
468 break;
469 case 7: {
470 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
471 /* Mask ebx against host capability word 9 */
472 if (index == 0) {
473 entry->ebx &= kvm_cpuid_7_0_ebx_x86_features;
474 cpuid_mask(&entry->ebx, CPUID_7_0_EBX);
475 // TSC_ADJUST is emulated
476 entry->ebx |= F(TSC_ADJUST);
477 entry->ecx &= kvm_cpuid_7_0_ecx_x86_features;
478 cpuid_mask(&entry->ecx, CPUID_7_ECX);
479 /* PKU is not yet implemented for shadow paging. */
480 if (!tdp_enabled || !boot_cpu_has(X86_FEATURE_OSPKE))
481 entry->ecx &= ~F(PKU);
482 entry->edx &= kvm_cpuid_7_0_edx_x86_features;
483 cpuid_mask(&entry->edx, CPUID_7_EDX);
484 } else {
485 entry->ebx = 0;
486 entry->ecx = 0;
487 entry->edx = 0;
488 }
489 entry->eax = 0;
490 break;
491 }
492 case 9:
493 break;
494 case 0xa: { /* Architectural Performance Monitoring */
495 struct x86_pmu_capability cap;
496 union cpuid10_eax eax;
497 union cpuid10_edx edx;
498
499 perf_get_x86_pmu_capability(&cap);
500
501 /*
502 * Only support guest architectural pmu on a host
503 * with architectural pmu.
504 */
505 if (!cap.version)
506 memset(&cap, 0, sizeof(cap));
507
508 eax.split.version_id = min(cap.version, 2);
509 eax.split.num_counters = cap.num_counters_gp;
510 eax.split.bit_width = cap.bit_width_gp;
511 eax.split.mask_length = cap.events_mask_len;
512
513 edx.split.num_counters_fixed = cap.num_counters_fixed;
514 edx.split.bit_width_fixed = cap.bit_width_fixed;
515 edx.split.reserved = 0;
516
517 entry->eax = eax.full;
518 entry->ebx = cap.events_mask;
519 entry->ecx = 0;
520 entry->edx = edx.full;
521 break;
522 }
523 /* function 0xb has additional index. */
524 case 0xb: {
525 int i, level_type;
526
527 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
528 /* read more entries until level_type is zero */
529 for (i = 1; ; ++i) {
530 if (*nent >= maxnent)
531 goto out;
532
533 level_type = entry[i - 1].ecx & 0xff00;
534 if (!level_type)
535 break;
536 do_cpuid_1_ent(&entry[i], function, i);
537 entry[i].flags |=
538 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
539 ++*nent;
540 }
541 break;
542 }
543 case 0xd: {
544 int idx, i;
545 u64 supported = kvm_supported_xcr0();
546
547 entry->eax &= supported;
548 entry->ebx = xstate_required_size(supported, false);
549 entry->ecx = entry->ebx;
550 entry->edx &= supported >> 32;
551 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
552 if (!supported)
553 break;
554
555 for (idx = 1, i = 1; idx < 64; ++idx) {
556 u64 mask = ((u64)1 << idx);
557 if (*nent >= maxnent)
558 goto out;
559
560 do_cpuid_1_ent(&entry[i], function, idx);
561 if (idx == 1) {
562 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
563 cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
564 entry[i].ebx = 0;
565 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
566 entry[i].ebx =
567 xstate_required_size(supported,
568 true);
569 } else {
570 if (entry[i].eax == 0 || !(supported & mask))
571 continue;
572 if (WARN_ON_ONCE(entry[i].ecx & 1))
573 continue;
574 }
575 entry[i].ecx = 0;
576 entry[i].edx = 0;
577 entry[i].flags |=
578 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
579 ++*nent;
580 ++i;
581 }
582 break;
583 }
584 case KVM_CPUID_SIGNATURE: {
585 static const char signature[12] = "KVMKVMKVM\0\0";
586 const u32 *sigptr = (const u32 *)signature;
587 entry->eax = KVM_CPUID_FEATURES;
588 entry->ebx = sigptr[0];
589 entry->ecx = sigptr[1];
590 entry->edx = sigptr[2];
591 break;
592 }
593 case KVM_CPUID_FEATURES:
594 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
595 (1 << KVM_FEATURE_NOP_IO_DELAY) |
596 (1 << KVM_FEATURE_CLOCKSOURCE2) |
597 (1 << KVM_FEATURE_ASYNC_PF) |
598 (1 << KVM_FEATURE_PV_EOI) |
599 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
600 (1 << KVM_FEATURE_PV_UNHALT) |
601 (1 << KVM_FEATURE_ASYNC_PF_VMEXIT);
602
603 if (sched_info_on())
604 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
605
606 entry->ebx = 0;
607 entry->ecx = 0;
608 entry->edx = 0;
609 break;
610 case 0x80000000:
611 entry->eax = min(entry->eax, 0x8000001a);
612 break;
613 case 0x80000001:
614 entry->edx &= kvm_cpuid_8000_0001_edx_x86_features;
615 cpuid_mask(&entry->edx, CPUID_8000_0001_EDX);
616 entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features;
617 cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX);
618 break;
619 case 0x80000007: /* Advanced power management */
620 /* invariant TSC is CPUID.80000007H:EDX[8] */
621 entry->edx &= (1 << 8);
622 /* mask against host */
623 entry->edx &= boot_cpu_data.x86_power;
624 entry->eax = entry->ebx = entry->ecx = 0;
625 break;
626 case 0x80000008: {
627 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
628 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
629 unsigned phys_as = entry->eax & 0xff;
630
631 if (!g_phys_as)
632 g_phys_as = phys_as;
633 entry->eax = g_phys_as | (virt_as << 8);
634 entry->edx = 0;
635 /* IBRS and IBPB aren't necessarily present in hardware cpuid */
636 if (boot_cpu_has(X86_FEATURE_IBPB))
637 entry->ebx |= F(IBPB);
638 if (boot_cpu_has(X86_FEATURE_IBRS))
639 entry->ebx |= F(IBRS);
640 entry->ebx &= kvm_cpuid_8000_0008_ebx_x86_features;
641 cpuid_mask(&entry->ebx, CPUID_8000_0008_EBX);
642 break;
643 }
644 case 0x80000019:
645 entry->ecx = entry->edx = 0;
646 break;
647 case 0x8000001a:
648 break;
649 case 0x8000001d:
650 break;
651 /*Add support for Centaur's CPUID instruction*/
652 case 0xC0000000:
653 /*Just support up to 0xC0000004 now*/
654 entry->eax = min(entry->eax, 0xC0000004);
655 break;
656 case 0xC0000001:
657 entry->edx &= kvm_cpuid_C000_0001_edx_x86_features;
658 cpuid_mask(&entry->edx, CPUID_C000_0001_EDX);
659 break;
660 case 3: /* Processor serial number */
661 case 5: /* MONITOR/MWAIT */
662 case 0xC0000002:
663 case 0xC0000003:
664 case 0xC0000004:
665 default:
666 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
667 break;
668 }
669
670 kvm_x86_ops->set_supported_cpuid(function, entry);
671
672 r = 0;
673
674out:
675 put_cpu();
676
677 return r;
678}
679
680static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
681 u32 idx, int *nent, int maxnent, unsigned int type)
682{
683 if (type == KVM_GET_EMULATED_CPUID)
684 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
685
686 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
687}
688
689#undef F
690
691struct kvm_cpuid_param {
692 u32 func;
693 u32 idx;
694 bool has_leaf_count;
695 bool (*qualifier)(const struct kvm_cpuid_param *param);
696};
697
698static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
699{
700 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
701}
702
703static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
704 __u32 num_entries, unsigned int ioctl_type)
705{
706 int i;
707 __u32 pad[3];
708
709 if (ioctl_type != KVM_GET_EMULATED_CPUID)
710 return false;
711
712 /*
713 * We want to make sure that ->padding is being passed clean from
714 * userspace in case we want to use it for something in the future.
715 *
716 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
717 * have to give ourselves satisfied only with the emulated side. /me
718 * sheds a tear.
719 */
720 for (i = 0; i < num_entries; i++) {
721 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
722 return true;
723
724 if (pad[0] || pad[1] || pad[2])
725 return true;
726 }
727 return false;
728}
729
730int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
731 struct kvm_cpuid_entry2 __user *entries,
732 unsigned int type)
733{
734 struct kvm_cpuid_entry2 *cpuid_entries;
735 int limit, nent = 0, r = -E2BIG, i;
736 u32 func;
737 static const struct kvm_cpuid_param param[] = {
738 { .func = 0, .has_leaf_count = true },
739 { .func = 0x80000000, .has_leaf_count = true },
740 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
741 { .func = KVM_CPUID_SIGNATURE },
742 { .func = KVM_CPUID_FEATURES },
743 };
744
745 if (cpuid->nent < 1)
746 goto out;
747 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
748 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
749
750 if (sanity_check_entries(entries, cpuid->nent, type))
751 return -EINVAL;
752
753 r = -ENOMEM;
754 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
755 if (!cpuid_entries)
756 goto out;
757
758 r = 0;
759 for (i = 0; i < ARRAY_SIZE(param); i++) {
760 const struct kvm_cpuid_param *ent = &param[i];
761
762 if (ent->qualifier && !ent->qualifier(ent))
763 continue;
764
765 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
766 &nent, cpuid->nent, type);
767
768 if (r)
769 goto out_free;
770
771 if (!ent->has_leaf_count)
772 continue;
773
774 limit = cpuid_entries[nent - 1].eax;
775 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
776 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
777 &nent, cpuid->nent, type);
778
779 if (r)
780 goto out_free;
781 }
782
783 r = -EFAULT;
784 if (copy_to_user(entries, cpuid_entries,
785 nent * sizeof(struct kvm_cpuid_entry2)))
786 goto out_free;
787 cpuid->nent = nent;
788 r = 0;
789
790out_free:
791 vfree(cpuid_entries);
792out:
793 return r;
794}
795
796static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
797{
798 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
799 struct kvm_cpuid_entry2 *ej;
800 int j = i;
801 int nent = vcpu->arch.cpuid_nent;
802
803 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
804 /* when no next entry is found, the current entry[i] is reselected */
805 do {
806 j = (j + 1) % nent;
807 ej = &vcpu->arch.cpuid_entries[j];
808 } while (ej->function != e->function);
809
810 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
811
812 return j;
813}
814
815/* find an entry with matching function, matching index (if needed), and that
816 * should be read next (if it's stateful) */
817static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
818 u32 function, u32 index)
819{
820 if (e->function != function)
821 return 0;
822 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
823 return 0;
824 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
825 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
826 return 0;
827 return 1;
828}
829
830struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
831 u32 function, u32 index)
832{
833 int i;
834 struct kvm_cpuid_entry2 *best = NULL;
835
836 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
837 struct kvm_cpuid_entry2 *e;
838
839 e = &vcpu->arch.cpuid_entries[i];
840 if (is_matching_cpuid_entry(e, function, index)) {
841 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
842 move_to_next_stateful_cpuid_entry(vcpu, i);
843 best = e;
844 break;
845 }
846 }
847 return best;
848}
849EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
850
851/*
852 * If no match is found, check whether we exceed the vCPU's limit
853 * and return the content of the highest valid _standard_ leaf instead.
854 * This is to satisfy the CPUID specification.
855 */
856static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
857 u32 function, u32 index)
858{
859 struct kvm_cpuid_entry2 *maxlevel;
860
861 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
862 if (!maxlevel || maxlevel->eax >= function)
863 return NULL;
864 if (function & 0x80000000) {
865 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
866 if (!maxlevel)
867 return NULL;
868 }
869 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
870}
871
872bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
873 u32 *ecx, u32 *edx, bool check_limit)
874{
875 u32 function = *eax, index = *ecx;
876 struct kvm_cpuid_entry2 *best;
877 bool entry_found = true;
878
879 best = kvm_find_cpuid_entry(vcpu, function, index);
880
881 if (!best) {
882 entry_found = false;
883 if (!check_limit)
884 goto out;
885
886 best = check_cpuid_limit(vcpu, function, index);
887 }
888
889out:
890 if (best) {
891 *eax = best->eax;
892 *ebx = best->ebx;
893 *ecx = best->ecx;
894 *edx = best->edx;
895 } else
896 *eax = *ebx = *ecx = *edx = 0;
897 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, entry_found);
898 return entry_found;
899}
900EXPORT_SYMBOL_GPL(kvm_cpuid);
901
902int kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
903{
904 u32 eax, ebx, ecx, edx;
905
906 if (cpuid_fault_enabled(vcpu) && !kvm_require_cpl(vcpu, 0))
907 return 1;
908
909 eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
910 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
911 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx, true);
912 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
913 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
914 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
915 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
916 return kvm_skip_emulated_instruction(vcpu);
917}
918EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
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