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| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2020-03-05 02:34:32 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-16 17:58:47 +0100 |
| commit | 15608ed03f10a1414188612b0ee9653e3c78bbd9 (patch) | |
| tree | ac09dad5dac942f2aece0e77a244c33326bdf0a8 /arch/x86/kvm/kvm_emulate.h | |
| parent | KVM: x86: Trace the original requested CPUID function in kvm_cpuid() (diff) | |
| download | linux-15608ed03f10a1414188612b0ee9653e3c78bbd9.tar.xz linux-15608ed03f10a1414188612b0ee9653e3c78bbd9.zip | |
KVM: x86: Add helpers to perform CPUID-based guest vendor check
Add helpers to provide CPUID-based guest vendor checks, i.e. to do the
ugly register comparisons. Use the new helpers to check for an AMD
guest vendor in guest_cpuid_is_amd() as well as in the existing emulator
flows.
Using the new helpers fixes a _very_ theoretical bug where
guest_cpuid_is_amd() would get a false positive on a non-AMD virtual CPU
with a vendor string beginning with "Auth" due to the previous logic
only checking EBX. It also fixes a marginally less theoretically bug
where guest_cpuid_is_amd() would incorrectly return false for a guest
CPU with "AMDisbetter!" as its vendor string.
Fixes: a0c0feb57992c ("KVM: x86: reserve bit 8 of non-leaf PDPEs and PML4Es in 64-bit mode on AMD")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/kvm_emulate.h')
| -rw-r--r-- | arch/x86/kvm/kvm_emulate.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h index f86fe6bf170d..b03a6a56e46e 100644 --- a/arch/x86/kvm/kvm_emulate.h +++ b/arch/x86/kvm/kvm_emulate.h @@ -396,6 +396,30 @@ struct x86_emulate_ctxt { #define X86EMUL_CPUID_VENDOR_GenuineIntel_ecx 0x6c65746e #define X86EMUL_CPUID_VENDOR_GenuineIntel_edx 0x49656e69 +static inline bool is_guest_vendor_intel(u32 ebx, u32 ecx, u32 edx) +{ + return ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx && + ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx && + edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx; +} + +static inline bool is_guest_vendor_amd(u32 ebx, u32 ecx, u32 edx) +{ + return (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx && + ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx && + edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx) || + (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx && + ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx && + edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx); +} + +static inline bool is_guest_vendor_hygon(u32 ebx, u32 ecx, u32 edx) +{ + return ebx == X86EMUL_CPUID_VENDOR_HygonGenuine_ebx && + ecx == X86EMUL_CPUID_VENDOR_HygonGenuine_ecx && + edx == X86EMUL_CPUID_VENDOR_HygonGenuine_edx; +} + enum x86_intercept_stage { X86_ICTP_NONE = 0, /* Allow zero-init to not match anything */ X86_ICPT_PRE_EXCEPT, |