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