diff options
| author | Sean Christopherson <[email protected]> | 2021-05-04 10:17:21 -0700 |
|---|---|---|
| committer | Paolo Bonzini <[email protected]> | 2021-05-07 06:06:15 -0400 |
| commit | 85d0011264da24be08ae907d7f29983a597ca9b1 (patch) | |
| tree | 337769183d8aad311c142ecef9eee3bbecb36225 | |
| parent | 8aec21c04caa2000f91cf8822ae0811e4b0c3971 (diff) | |
KVM: x86: Emulate RDPID only if RDTSCP is supported
Do not advertise emulation support for RDPID if RDTSCP is unsupported.
RDPID emulation subtly relies on MSR_TSC_AUX to exist in hardware, as
both vmx_get_msr() and svm_get_msr() will return an error if the MSR is
unsupported, i.e. ctxt->ops->get_msr() will fail and the emulator will
inject a #UD.
Note, RDPID emulation also relies on RDTSCP being enabled in the guest,
but this is a KVM bug and will eventually be fixed.
Fixes: fb6d4d340e05 ("KVM: x86: emulate RDPID")
Cc: [email protected]
Signed-off-by: Sean Christopherson <[email protected]>
Message-Id: <[email protected]>
Reviewed-by: Jim Mattson <[email protected]>
Reviewed-by: Reiji Watanabe <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 19606a341888..c0e8c5e92189 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -637,7 +637,8 @@ static int __do_cpuid_func_emulated(struct kvm_cpuid_array *array, u32 func) case 7: entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; entry->eax = 0; - entry->ecx = F(RDPID); + if (kvm_cpu_cap_has(X86_FEATURE_RDTSCP)) + entry->ecx = F(RDPID); ++array->nent; default: break; |