KVM: arm/arm64: vgic-new: Synchronize changes to active state
[cascardo/linux.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);