Re: [PATCH RFC v7 03/64] KVM: SVM: Advertise private memory support to KVM

From: Sean Christopherson
Date: Wed Jan 18 2023 - 16:34:05 EST


On Wed, Jan 18, 2023, Huang, Kai wrote:
> On Wed, 2022-12-14 at 13:39 -0600, Michael Roth wrote:
> > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> > index 91352d692845..7f3e4d91c0c6 100644
> > --- a/arch/x86/kvm/svm/svm.c
> > +++ b/arch/x86/kvm/svm/svm.c
> > @@ -4694,6 +4694,14 @@ static int svm_vm_init(struct kvm *kvm)
> > return 0;
> > }
> >
> > +static int svm_private_mem_enabled(struct kvm *kvm)
> > +{
> > + if (sev_guest(kvm))
> > + return kvm->arch.upm_mode ? 1 : 0;
> > +
> > + return IS_ENABLED(CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING) ? 1 : 0;
> > +}
> > +
>
> Is this new callback really needed?

Probably not. For anything in this series that gets within spitting distance of
CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING, my recommendation is to make a mental note
but otherwise ignore things like this for now. I suspect it will be much, much
more efficient to sort all of this out when I smush UPM+SNP+TDX together in a few
weeks.