On Mon, Feb 26, 2024 at 02:03:32PM -0500, Paolo Bonzini wrote:
> From: Sean Christopherson <seanjc@xxxxxxxxxx>
>
> Leave SEV and SEV_ES '0' in kvm_cpu_caps by default, and instead set them
> in sev_set_cpu_caps() if SEV and SEV-ES support are fully enabled. Aside
> from the fact that sev_set_cpu_caps() is wildly misleading when it *clears*
> capabilities, this will allow compiling out sev.c without falsely
> advertising SEV/SEV-ES support in KVM_GET_SUPPORTED_CPUID.
>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Reviewed-by: Michael Roth <michael.roth@xxxxxxx>
> ---
> arch/x86/kvm/cpuid.c | 2 +-
> arch/x86/kvm/svm/sev.c | 8 ++++----
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index adba49afb5fe..bde4df13a7e8 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -761,7 +761,7 @@ void kvm_set_cpu_caps(void)
> kvm_cpu_cap_mask(CPUID_8000_000A_EDX, 0);
>
> kvm_cpu_cap_mask(CPUID_8000_001F_EAX,
> - 0 /* SME */ | F(SEV) | 0 /* VM_PAGE_FLUSH */ | F(SEV_ES) |
> + 0 /* SME */ | 0 /* SEV */ | 0 /* VM_PAGE_FLUSH */ | 0 /* SEV_ES */ |
> F(SME_COHERENT));
>
> kvm_cpu_cap_mask(CPUID_8000_0021_EAX,
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index f06f9e51ad9d..aec3453fd73c 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -2178,10 +2178,10 @@ void sev_vm_destroy(struct kvm *kvm)
>
> void __init sev_set_cpu_caps(void)
> {
> - if (!sev_enabled)
> - kvm_cpu_cap_clear(X86_FEATURE_SEV);
> - if (!sev_es_enabled)
> - kvm_cpu_cap_clear(X86_FEATURE_SEV_ES);
> + if (sev_enabled)
> + kvm_cpu_cap_set(X86_FEATURE_SEV);
> + if (sev_es_enabled)
> + kvm_cpu_cap_set(X86_FEATURE_SEV_ES);
> }
>
> void __init sev_hardware_setup(void)
> --
> 2.39.1
>
>
