Re: [PATCH v7 1/9] KVM: x86: Define KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT

[Sean Christopherson]

On Fri, Mar 27, 2026, Jim Mattson wrote:
> diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
> index ff1e4b4dc998..74014110b550 100644
> --- a/arch/x86/kvm/svm/svm.h
> +++ b/arch/x86/kvm/svm/svm.h
> @@ -616,6 +616,17 @@ static inline bool nested_npt_enabled(struct vcpu_svm *svm)
>  	return svm->nested.ctl.misc_ctl & SVM_MISC_ENABLE_NP;
>  }
>  
> +static inline bool l2_has_separate_pat(struct vcpu_svm *svm)

Take @vcpu instead of @svm.  All of the callers have a "vcpu", but not all have
a local "svm".  That will shorten the quirk check far enough to let it poke out.

> +{
> +	/*
> +	 * If KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled while a vCPU
> +	 * is running, the L2 IA32_PAT semantics for that vCPU are undefined.
> +	 */
> +	return nested_npt_enabled(svm) &&
> +		!kvm_check_has_quirk(svm->vcpu.kvm,
> +				     KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT);

Align indentation.  With the @svm => @vcpu change, this becomes:

	return nested_npt_enabled(to_svm(vcpu)) &&
	       !kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT);

> +}
> +
>  static inline bool nested_vnmi_enabled(struct vcpu_svm *svm)
>  {
>  	return guest_cpu_cap_has(&svm->vcpu, X86_FEATURE_VNMI) &&
> -- 
> 2.53.0.1018.g2bb0e51243-goog
>