Re: [PATCH v13 16/40] KVM: arm64: Manage GCS access and registers for guests

[Marc Zyngier]

On Wed, 02 Oct 2024 01:24:25 +0100,
Marc Zyngier <maz@xxxxxxxxxx> wrote:
> 
> On Tue, 01 Oct 2024 23:58:55 +0100,
> Mark Brown <broonie@xxxxxxxxxx> wrote:
> 
> > @@ -4714,6 +4735,10 @@ void kvm_calculate_traps(struct kvm_vcpu *vcpu)
> >  		kvm->arch.fgu[HFGxTR_GROUP] |= (HFGxTR_EL2_nPOR_EL1 |
> >  						HFGxTR_EL2_nPOR_EL0);
> >  
> > +	if (!kvm_has_gcs(kvm))
> > +		kvm->arch.fgu[HFGxTR_GROUP] |= (HFGxTR_EL2_nGCS_EL0 |
> > +						HFGxTR_EL2_nGCS_EL1);
> > +
> 
> Why are you still allowing the GCS instructions when GCS isn't
> enabled?

Scratch that, they are NOPs when GCS isn't enabled, so there shouldn't
be any need for extra traps.

	M.

-- 
Without deviation from the norm, progress is not possible.