[PATCH v15 2/6] KVM: arm64: Manage GCS access and registers for guests

[Mark Brown]

On Wed, Aug 20, 2025 at 10:06:49PM +0100, Marc Zyngier wrote:
> Mark Brown <broonie at kernel.org> wrote:

> > In order to allow userspace to control availability of the feature to
> > guests we enable writability for only ID_AA64PFR1_EL1.GCS, this is a
> > deliberately conservative choice to avoid errors due to oversights.
> > Further fields should be made writable in future.

> I'm not sure what you mean by that. Making the feature field writable
> is only allowable if we have some level of support (and otherwise we
> should prevent both the feature being exposed, and the field being
> writable).

> So future fields being writable will only happen when the features are
> fully supported, and only then.

> Please clarify, or drop this altogether.

That's bitrot from earlier versions where we needed to enable
ID_AA64PFR1_EL1, the other versions were similar.  I'll remove these
stale references.
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