Re: [PATCH 26/28] KVM: SVM: enable GMET and set it in MMU role

From: Paolo Bonzini

Date: Fri May 01 2026 - 00:00:11 EST


On Thu, Apr 30, 2026 at 9:15 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
>
> On Thu, Apr 30, 2026, Paolo Bonzini wrote:
> > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> > index e7fdd7a9c280..3895d8794366 100644
> > --- a/arch/x86/kvm/svm/svm.c
> > +++ b/arch/x86/kvm/svm/svm.c
> > @@ -138,6 +138,9 @@ module_param(pause_filter_count_max, ushort, 0444);
> > bool __ro_after_init npt_enabled = true;
> > module_param_named(npt, npt_enabled, bool, 0444);
> >
> > +bool gmet_enabled = true;
>
> This really should be hardcoded false, with no module param, until "enable GMET
> for guests". Otherwise stopping here means KVM is over-reporting support.

Are module parameters reporting support of nested features? I thought
of these as "does KVM know about MBEC/GMET".

This is I think the only point where I disagree, I think. I'll fix up
patches 6/7/8/17.

Paolo