diff options
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index c1a8d5744690..8fc07af8f72d 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -600,18 +600,37 @@ int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, return 0; } -/* Mask kvm_cpu_caps for @leaf with the raw CPUID capabilities of this CPU. */ -static __always_inline void __kvm_cpu_cap_mask(unsigned int leaf) +static __always_inline u32 raw_cpuid_get(struct cpuid_reg cpuid) { - const struct cpuid_reg cpuid = x86_feature_cpuid(leaf * 32); struct kvm_cpuid_entry2 entry; + u32 base; - reverse_cpuid_check(leaf); + /* + * KVM only supports features defined by Intel (0x0), AMD (0x80000000), + * and Centaur (0xc0000000). WARN if a feature for new vendor base is + * defined, as this and other code would need to be updated. + */ + base = cpuid.function & 0xffff0000; + if (WARN_ON_ONCE(base && base != 0x80000000 && base != 0xc0000000)) + return 0; + + if (cpuid_eax(base) < cpuid.function) + return 0; cpuid_count(cpuid.function, cpuid.index, &entry.eax, &entry.ebx, &entry.ecx, &entry.edx); - kvm_cpu_caps[leaf] &= *__cpuid_entry_get_reg(&entry, cpuid.reg); + return *__cpuid_entry_get_reg(&entry, cpuid.reg); +} + +/* Mask kvm_cpu_caps for @leaf with the raw CPUID capabilities of this CPU. */ +static __always_inline void __kvm_cpu_cap_mask(unsigned int leaf) +{ + const struct cpuid_reg cpuid = x86_feature_cpuid(leaf * 32); + + reverse_cpuid_check(leaf); + + kvm_cpu_caps[leaf] &= raw_cpuid_get(cpuid); } static __always_inline |