Re: [PATCH 2/3] KVM: arm64: Teach address translation about access faults

[Marc Zyngier <maz@kernel.org>]

On Tue, 22 Apr 2025 21:54:26 +0100,
D Scott Phillips <scott@os.amperecomputing.com> wrote:
> 
> Marc Zyngier <maz@kernel.org> writes:
> 
> > It appears that our S1 PTW is completely oblivious of access faults.
> > Teach the S1 translation code about it.
> >
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> > ---
> >  arch/arm64/kvm/at.c | 26 +++++++++++++++++++++-----
> >  1 file changed, 21 insertions(+), 5 deletions(-)
> >
> > diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
> > index 3a4568e2de910..c40583edebc4f 100644
> > --- a/arch/arm64/kvm/at.c
> > +++ b/arch/arm64/kvm/at.c
> > @@ -456,6 +456,11 @@ static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
> >  	if (check_output_size(desc & GENMASK(47, va_bottom), wi))
> >  		goto addrsz;
> >  
> > +	if (!(desc & PTE_AF)) {
> 
> Shouldn't this depend on TCR_ELx.HA == 0?

Which is so far the only supported configuration for a guest under NV.

	M.

-- 
Jazz isn't dead. It just smells funny.