diff options
| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2020-03-03 00:56:26 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-16 17:58:11 +0100 |
| commit | 7392079c4e740572a5af72a7223ef5e162e442c9 (patch) | |
| tree | 69bdea208fcc16adee95d2e44689a233692b744e /arch/x86/kvm/cpuid.c | |
| parent | KVM: x86: Make kvm_mpx_supported() an inline function (diff) | |
| download | linux-7392079c4e740572a5af72a7223ef5e162e442c9.tar.xz linux-7392079c4e740572a5af72a7223ef5e162e442c9.zip | |
KVM: x86: Clear output regs for CPUID 0x14 if PT isn't exposed to guest
Clear the output regs for the main CPUID 0x14 leaf (index=0) if Intel PT
isn't exposed to the guest. Leaf 0x14 enumerates Intel PT capabilities
and should return zeroes if PT is not supported. Incorrectly reporting
PT capabilities is essentially a cosmetic error, i.e. doesn't negatively
affect any known userspace/kernel, as the existence of PT itself is
correctly enumerated via CPUID 0x7.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 1ff16300a468..c194e49622b9 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -663,8 +663,10 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) break; /* Intel PT */ case 0x14: - if (!f_intel_pt) + if (!f_intel_pt) { + entry->eax = entry->ebx = entry->ecx = entry->edx = 0; break; + } for (i = 1, max_idx = entry->eax; i <= max_idx; ++i) { if (!do_host_cpuid(array, function, i)) |