Re: [PATCH 51/61] KVM: x86: Use kvm_cpu_caps to detect Intel PT support

From: Vitaly Kuznetsov
Date: Tue Feb 25 2020 - 09:07:07 EST


Sean Christopherson <sean.j.christopherson@xxxxxxxxx> writes:

> Check for Intel PT using kvm_cpu_cap_has() to pave the way toward
> eliminating ->pt_supported().
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> ---
> arch/x86/kvm/cpuid.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index a37cb6fda979..3d287fc6eb6e 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -507,7 +507,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
> {
> struct kvm_cpuid_entry2 *entry;
> int r, i, max_idx;
> - unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0;
>
> /* all calls to cpuid_count() should be made on the same cpu */
> get_cpu();
> @@ -687,7 +686,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
> break;
> /* Intel PT */
> case 0x14:
> - if (!f_intel_pt) {
> + if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT)) {
> entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
> break;
> }

Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

--
Vitaly