| /* |
| * Kernel-based Virtual Machine driver for Linux |
| * cpuid support routines |
| * |
| * derived from arch/x86/kvm/x86.c |
| * |
| * Copyright 2011 Red Hat, Inc. and/or its affiliates. |
| * Copyright IBM Corporation, 2008 |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2. See |
| * the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include <linux/kvm_host.h> |
| #include <linux/module.h> |
| #include <linux/vmalloc.h> |
| #include <linux/uaccess.h> |
| #include <asm/user.h> |
| #include <asm/xsave.h> |
| #include "cpuid.h" |
| #include "lapic.h" |
| #include "mmu.h" |
| #include "trace.h" |
| |
| void kvm_update_cpuid(struct kvm_vcpu *vcpu) |
| { |
| struct kvm_cpuid_entry2 *best; |
| struct kvm_lapic *apic = vcpu->arch.apic; |
| |
| best = kvm_find_cpuid_entry(vcpu, 1, 0); |
| if (!best) |
| return; |
| |
| /* Update OSXSAVE bit */ |
| if (cpu_has_xsave && best->function == 0x1) { |
| best->ecx &= ~(bit(X86_FEATURE_OSXSAVE)); |
| if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) |
| best->ecx |= bit(X86_FEATURE_OSXSAVE); |
| } |
| |
| if (apic) { |
| if (best->ecx & bit(X86_FEATURE_TSC_DEADLINE_TIMER)) |
| apic->lapic_timer.timer_mode_mask = 3 << 17; |
| else |
| apic->lapic_timer.timer_mode_mask = 1 << 17; |
| } |
| |
| kvm_pmu_cpuid_update(vcpu); |
| } |
| |
| static int is_efer_nx(void) |
| { |
| unsigned long long efer = 0; |
| |
| rdmsrl_safe(MSR_EFER, &efer); |
| return efer & EFER_NX; |
| } |
| |
| static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu) |
| { |
| int i; |
| struct kvm_cpuid_entry2 *e, *entry; |
| |
| entry = NULL; |
| for (i = 0; i < vcpu->arch.cpuid_nent; ++i) { |
| e = &vcpu->arch.cpuid_entries[i]; |
| if (e->function == 0x80000001) { |
| entry = e; |
| break; |
| } |
| } |
| if (entry && (entry->edx & (1 << 20)) && !is_efer_nx()) { |
| entry->edx &= ~(1 << 20); |
| printk(KERN_INFO "kvm: guest NX capability removed\n"); |
| } |
| } |
| |
| /* when an old userspace process fills a new kernel module */ |
| int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, |
| struct kvm_cpuid *cpuid, |
| struct kvm_cpuid_entry __user *entries) |
| { |
| int r, i; |
| struct kvm_cpuid_entry *cpuid_entries; |
| |
| r = -E2BIG; |
| if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) |
| goto out; |
| r = -ENOMEM; |
| cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) * cpuid->nent); |
| if (!cpuid_entries) |
| goto out; |
| r = -EFAULT; |
| if (copy_from_user(cpuid_entries, entries, |
| cpuid->nent * sizeof(struct kvm_cpuid_entry))) |
| goto out_free; |
| for (i = 0; i < cpuid->nent; i++) { |
| vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function; |
| vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax; |
| vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx; |
| vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx; |
| vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx; |
| vcpu->arch.cpuid_entries[i].index = 0; |
| vcpu->arch.cpuid_entries[i].flags = 0; |
| vcpu->arch.cpuid_entries[i].padding[0] = 0; |
| vcpu->arch.cpuid_entries[i].padding[1] = 0; |
| vcpu->arch.cpuid_entries[i].padding[2] = 0; |
| } |
| vcpu->arch.cpuid_nent = cpuid->nent; |
| cpuid_fix_nx_cap(vcpu); |
| r = 0; |
| kvm_apic_set_version(vcpu); |
| kvm_x86_ops->cpuid_update(vcpu); |
| kvm_update_cpuid(vcpu); |
| |
| out_free: |
| vfree(cpuid_entries); |
| out: |
| return r; |
| } |
| |
| int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, |
| struct kvm_cpuid2 *cpuid, |
| struct kvm_cpuid_entry2 __user *entries) |
| { |
| int r; |
| |
| r = -E2BIG; |
| if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) |
| goto out; |
| r = -EFAULT; |
| if (copy_from_user(&vcpu->arch.cpuid_entries, entries, |
| cpuid->nent * sizeof(struct kvm_cpuid_entry2))) |
| goto out; |
| vcpu->arch.cpuid_nent = cpuid->nent; |
| kvm_apic_set_version(vcpu); |
| kvm_x86_ops->cpuid_update(vcpu); |
| kvm_update_cpuid(vcpu); |
| return 0; |
| |
| out: |
| return r; |
| } |
| |
| int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, |
| struct kvm_cpuid2 *cpuid, |
| struct kvm_cpuid_entry2 __user *entries) |
| { |
| int r; |
| |
| r = -E2BIG; |
| if (cpuid->nent < vcpu->arch.cpuid_nent) |
| goto out; |
| r = -EFAULT; |
| if (copy_to_user(entries, &vcpu->arch.cpuid_entries, |
| vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2))) |
| goto out; |
| return 0; |
| |
| out: |
| cpuid->nent = vcpu->arch.cpuid_nent; |
| return r; |
| } |
| |
| static void cpuid_mask(u32 *word, int wordnum) |
| { |
| *word &= boot_cpu_data.x86_capability[wordnum]; |
| } |
| |
| static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function, |
| u32 index) |
| { |
| entry->function = function; |
| entry->index = index; |
| cpuid_count(entry->function, entry->index, |
| &entry->eax, &entry->ebx, &entry->ecx, &entry->edx); |
| entry->flags = 0; |
| } |
| |
| static bool supported_xcr0_bit(unsigned bit) |
| { |
| u64 mask = ((u64)1 << bit); |
| |
| return mask & (XSTATE_FP | XSTATE_SSE | XSTATE_YMM) & host_xcr0; |
| } |
| |
| #define F(x) bit(X86_FEATURE_##x) |
| |
| static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, |
| u32 index, int *nent, int maxnent) |
| { |
| int r; |
| unsigned f_nx = is_efer_nx() ? F(NX) : 0; |
| #ifdef CONFIG_X86_64 |
| unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL) |
| ? F(GBPAGES) : 0; |
| unsigned f_lm = F(LM); |
| #else |
| unsigned f_gbpages = 0; |
| unsigned f_lm = 0; |
| #endif |
| unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0; |
| unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0; |
| |
| /* cpuid 1.edx */ |
| const u32 kvm_supported_word0_x86_features = |
| F(FPU) | F(VME) | F(DE) | F(PSE) | |
| F(TSC) | F(MSR) | F(PAE) | F(MCE) | |
| F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) | |
| F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | |
| F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLSH) | |
| 0 /* Reserved, DS, ACPI */ | F(MMX) | |
| F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) | |
| 0 /* HTT, TM, Reserved, PBE */; |
| /* cpuid 0x80000001.edx */ |
| const u32 kvm_supported_word1_x86_features = |
| F(FPU) | F(VME) | F(DE) | F(PSE) | |
| F(TSC) | F(MSR) | F(PAE) | F(MCE) | |
| F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) | |
| F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | |
| F(PAT) | F(PSE36) | 0 /* Reserved */ | |
| f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) | |
| F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp | |
| 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW); |
| /* cpuid 1.ecx */ |
| const u32 kvm_supported_word4_x86_features = |
| F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ | |
| 0 /* DS-CPL, VMX, SMX, EST */ | |
| 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ | |
| F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ | |
| F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) | |
| F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) | |
| 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) | |
| F(F16C) | F(RDRAND); |
| /* cpuid 0x80000001.ecx */ |
| const u32 kvm_supported_word6_x86_features = |
| F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ | |
| F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) | |
| F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) | |
| 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM); |
| |
| /* cpuid 0xC0000001.edx */ |
| const u32 kvm_supported_word5_x86_features = |
| F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) | |
| F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) | |
| F(PMM) | F(PMM_EN); |
| |
| /* cpuid 7.0.ebx */ |
| const u32 kvm_supported_word9_x86_features = |
| F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) | |
| F(BMI2) | F(ERMS) | f_invpcid | F(RTM); |
| |
| /* all calls to cpuid_count() should be made on the same cpu */ |
| get_cpu(); |
| |
| r = -E2BIG; |
| |
| if (*nent >= maxnent) |
| goto out; |
| |
| do_cpuid_1_ent(entry, function, index); |
| ++*nent; |
| |
| switch (function) { |
| case 0: |
| entry->eax = min(entry->eax, (u32)0xd); |
| break; |
| case 1: |
| entry->edx &= kvm_supported_word0_x86_features; |
| cpuid_mask(&entry->edx, 0); |
| entry->ecx &= kvm_supported_word4_x86_features; |
| cpuid_mask(&entry->ecx, 4); |
| /* we support x2apic emulation even if host does not support |
| * it since we emulate x2apic in software */ |
| entry->ecx |= F(X2APIC); |
| break; |
| /* function 2 entries are STATEFUL. That is, repeated cpuid commands |
| * may return different values. This forces us to get_cpu() before |
| * issuing the first command, and also to emulate this annoying behavior |
| * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */ |
| case 2: { |
| int t, times = entry->eax & 0xff; |
| |
| entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; |
| entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; |
| for (t = 1; t < times; ++t) { |
| if (*nent >= maxnent) |
| goto out; |
| |
| do_cpuid_1_ent(&entry[t], function, 0); |
| entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; |
| ++*nent; |
| } |
| break; |
| } |
| /* function 4 has additional index. */ |
| case 4: { |
| int i, cache_type; |
| |
| entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| /* read more entries until cache_type is zero */ |
| for (i = 1; ; ++i) { |
| if (*nent >= maxnent) |
| goto out; |
| |
| cache_type = entry[i - 1].eax & 0x1f; |
| if (!cache_type) |
| break; |
| do_cpuid_1_ent(&entry[i], function, i); |
| entry[i].flags |= |
| KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| ++*nent; |
| } |
| break; |
| } |
| case 7: { |
| entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| /* Mask ebx against host capbability word 9 */ |
| if (index == 0) { |
| entry->ebx &= kvm_supported_word9_x86_features; |
| cpuid_mask(&entry->ebx, 9); |
| } else |
| entry->ebx = 0; |
| entry->eax = 0; |
| entry->ecx = 0; |
| entry->edx = 0; |
| break; |
| } |
| case 9: |
| break; |
| case 0xa: { /* Architectural Performance Monitoring */ |
| struct x86_pmu_capability cap; |
| union cpuid10_eax eax; |
| union cpuid10_edx edx; |
| |
| perf_get_x86_pmu_capability(&cap); |
| |
| /* |
| * Only support guest architectural pmu on a host |
| * with architectural pmu. |
| */ |
| if (!cap.version) |
| memset(&cap, 0, sizeof(cap)); |
| |
| eax.split.version_id = min(cap.version, 2); |
| eax.split.num_counters = cap.num_counters_gp; |
| eax.split.bit_width = cap.bit_width_gp; |
| eax.split.mask_length = cap.events_mask_len; |
| |
| edx.split.num_counters_fixed = cap.num_counters_fixed; |
| edx.split.bit_width_fixed = cap.bit_width_fixed; |
| edx.split.reserved = 0; |
| |
| entry->eax = eax.full; |
| entry->ebx = cap.events_mask; |
| entry->ecx = 0; |
| entry->edx = edx.full; |
| break; |
| } |
| /* function 0xb has additional index. */ |
| case 0xb: { |
| int i, level_type; |
| |
| entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| /* read more entries until level_type is zero */ |
| for (i = 1; ; ++i) { |
| if (*nent >= maxnent) |
| goto out; |
| |
| level_type = entry[i - 1].ecx & 0xff00; |
| if (!level_type) |
| break; |
| do_cpuid_1_ent(&entry[i], function, i); |
| entry[i].flags |= |
| KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| ++*nent; |
| } |
| break; |
| } |
| case 0xd: { |
| int idx, i; |
| |
| entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| for (idx = 1, i = 1; idx < 64; ++idx) { |
| if (*nent >= maxnent) |
| goto out; |
| |
| do_cpuid_1_ent(&entry[i], function, idx); |
| if (entry[i].eax == 0 || !supported_xcr0_bit(idx)) |
| continue; |
| entry[i].flags |= |
| KVM_CPUID_FLAG_SIGNIFCANT_INDEX; |
| ++*nent; |
| ++i; |
| } |
| break; |
| } |
| case KVM_CPUID_SIGNATURE: { |
| char signature[12] = "KVMKVMKVM\0\0"; |
| u32 *sigptr = (u32 *)signature; |
| entry->eax = KVM_CPUID_FEATURES; |
| entry->ebx = sigptr[0]; |
| entry->ecx = sigptr[1]; |
| entry->edx = sigptr[2]; |
| break; |
| } |
| case KVM_CPUID_FEATURES: |
| entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) | |
| (1 << KVM_FEATURE_NOP_IO_DELAY) | |
| (1 << KVM_FEATURE_CLOCKSOURCE2) | |
| (1 << KVM_FEATURE_ASYNC_PF) | |
| (1 << KVM_FEATURE_PV_EOI) | |
| (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT); |
| |
| if (sched_info_on()) |
| entry->eax |= (1 << KVM_FEATURE_STEAL_TIME); |
| |
| entry->ebx = 0; |
| entry->ecx = 0; |
| entry->edx = 0; |
| break; |
| case 0x80000000: |
| entry->eax = min(entry->eax, 0x8000001a); |
| break; |
| case 0x80000001: |
| entry->edx &= kvm_supported_word1_x86_features; |
| cpuid_mask(&entry->edx, 1); |
| entry->ecx &= kvm_supported_word6_x86_features; |
| cpuid_mask(&entry->ecx, 6); |
| break; |
| case 0x80000008: { |
| unsigned g_phys_as = (entry->eax >> 16) & 0xff; |
| unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U); |
| unsigned phys_as = entry->eax & 0xff; |
| |
| if (!g_phys_as) |
| g_phys_as = phys_as; |
| entry->eax = g_phys_as | (virt_as << 8); |
| entry->ebx = entry->edx = 0; |
| break; |
| } |
| case 0x80000019: |
| entry->ecx = entry->edx = 0; |
| break; |
| case 0x8000001a: |
| break; |
| case 0x8000001d: |
| break; |
| /*Add support for Centaur's CPUID instruction*/ |
| case 0xC0000000: |
| /*Just support up to 0xC0000004 now*/ |
| entry->eax = min(entry->eax, 0xC0000004); |
| break; |
| case 0xC0000001: |
| entry->edx &= kvm_supported_word5_x86_features; |
| cpuid_mask(&entry->edx, 5); |
| break; |
| case 3: /* Processor serial number */ |
| case 5: /* MONITOR/MWAIT */ |
| case 6: /* Thermal management */ |
| case 0x80000007: /* Advanced power management */ |
| case 0xC0000002: |
| case 0xC0000003: |
| case 0xC0000004: |
| default: |
| entry->eax = entry->ebx = entry->ecx = entry->edx = 0; |
| break; |
| } |
| |
| kvm_x86_ops->set_supported_cpuid(function, entry); |
| |
| r = 0; |
| |
| out: |
| put_cpu(); |
| |
| return r; |
| } |
| |
| #undef F |
| |
| struct kvm_cpuid_param { |
| u32 func; |
| u32 idx; |
| bool has_leaf_count; |
| bool (*qualifier)(struct kvm_cpuid_param *param); |
| }; |
| |
| static bool is_centaur_cpu(struct kvm_cpuid_param *param) |
| { |
| return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR; |
| } |
| |
| int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid, |
| struct kvm_cpuid_entry2 __user *entries) |
| { |
| struct kvm_cpuid_entry2 *cpuid_entries; |
| int limit, nent = 0, r = -E2BIG, i; |
| u32 func; |
| static struct kvm_cpuid_param param[] = { |
| { .func = 0, .has_leaf_count = true }, |
| { .func = 0x80000000, .has_leaf_count = true }, |
| { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true }, |
| { .func = KVM_CPUID_SIGNATURE }, |
| { .func = KVM_CPUID_FEATURES }, |
| }; |
| |
| if (cpuid->nent < 1) |
| goto out; |
| if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) |
| cpuid->nent = KVM_MAX_CPUID_ENTRIES; |
| r = -ENOMEM; |
| cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent); |
| if (!cpuid_entries) |
| goto out; |
| |
| r = 0; |
| for (i = 0; i < ARRAY_SIZE(param); i++) { |
| struct kvm_cpuid_param *ent = ¶m[i]; |
| |
| if (ent->qualifier && !ent->qualifier(ent)) |
| continue; |
| |
| r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx, |
| &nent, cpuid->nent); |
| |
| if (r) |
| goto out_free; |
| |
| if (!ent->has_leaf_count) |
| continue; |
| |
| limit = cpuid_entries[nent - 1].eax; |
| for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func) |
| r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx, |
| &nent, cpuid->nent); |
| |
| if (r) |
| goto out_free; |
| } |
| |
| r = -EFAULT; |
| if (copy_to_user(entries, cpuid_entries, |
| nent * sizeof(struct kvm_cpuid_entry2))) |
| goto out_free; |
| cpuid->nent = nent; |
| r = 0; |
| |
| out_free: |
| vfree(cpuid_entries); |
| out: |
| return r; |
| } |
| |
| static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i) |
| { |
| struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i]; |
| int j, nent = vcpu->arch.cpuid_nent; |
| |
| e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT; |
| /* when no next entry is found, the current entry[i] is reselected */ |
| for (j = i + 1; ; j = (j + 1) % nent) { |
| struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j]; |
| if (ej->function == e->function) { |
| ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; |
| return j; |
| } |
| } |
| return 0; /* silence gcc, even though control never reaches here */ |
| } |
| |
| /* find an entry with matching function, matching index (if needed), and that |
| * should be read next (if it's stateful) */ |
| static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e, |
| u32 function, u32 index) |
| { |
| if (e->function != function) |
| return 0; |
| if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index) |
| return 0; |
| if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) && |
| !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT)) |
| return 0; |
| return 1; |
| } |
| |
| struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, |
| u32 function, u32 index) |
| { |
| int i; |
| struct kvm_cpuid_entry2 *best = NULL; |
| |
| for (i = 0; i < vcpu->arch.cpuid_nent; ++i) { |
| struct kvm_cpuid_entry2 *e; |
| |
| e = &vcpu->arch.cpuid_entries[i]; |
| if (is_matching_cpuid_entry(e, function, index)) { |
| if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) |
| move_to_next_stateful_cpuid_entry(vcpu, i); |
| best = e; |
| break; |
| } |
| } |
| return best; |
| } |
| EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry); |
| |
| int cpuid_maxphyaddr(struct kvm_vcpu *vcpu) |
| { |
| struct kvm_cpuid_entry2 *best; |
| |
| best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0); |
| if (!best || best->eax < 0x80000008) |
| goto not_found; |
| best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0); |
| if (best) |
| return best->eax & 0xff; |
| not_found: |
| return 36; |
| } |
| |
| /* |
| * If no match is found, check whether we exceed the vCPU's limit |
| * and return the content of the highest valid _standard_ leaf instead. |
| * This is to satisfy the CPUID specification. |
| */ |
| static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu, |
| u32 function, u32 index) |
| { |
| struct kvm_cpuid_entry2 *maxlevel; |
| |
| maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0); |
| if (!maxlevel || maxlevel->eax >= function) |
| return NULL; |
| if (function & 0x80000000) { |
| maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0); |
| if (!maxlevel) |
| return NULL; |
| } |
| return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index); |
| } |
| |
| void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) |
| { |
| u32 function = *eax, index = *ecx; |
| struct kvm_cpuid_entry2 *best; |
| |
| best = kvm_find_cpuid_entry(vcpu, function, index); |
| |
| if (!best) |
| best = check_cpuid_limit(vcpu, function, index); |
| |
| if (best) { |
| *eax = best->eax; |
| *ebx = best->ebx; |
| *ecx = best->ecx; |
| *edx = best->edx; |
| } else |
| *eax = *ebx = *ecx = *edx = 0; |
| } |
| |
| void kvm_emulate_cpuid(struct kvm_vcpu *vcpu) |
| { |
| u32 function, eax, ebx, ecx, edx; |
| |
| function = eax = kvm_register_read(vcpu, VCPU_REGS_RAX); |
| ecx = kvm_register_read(vcpu, VCPU_REGS_RCX); |
| kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx); |
| kvm_register_write(vcpu, VCPU_REGS_RAX, eax); |
| kvm_register_write(vcpu, VCPU_REGS_RBX, ebx); |
| kvm_register_write(vcpu, VCPU_REGS_RCX, ecx); |
| kvm_register_write(vcpu, VCPU_REGS_RDX, edx); |
| kvm_x86_ops->skip_emulated_instruction(vcpu); |
| trace_kvm_cpuid(function, eax, ebx, ecx, edx); |
| } |
| EXPORT_SYMBOL_GPL(kvm_emulate_cpuid); |