[PATCH v1 1/3] KVM: arm64: Hide S1POE from guests when not supported by the host

[Marc Zyngier]

On Thu, 12 Feb 2026 18:53:05 +0000,
Fuad Tabba <tabba at google.com> wrote:

> Ouch! Yeah, no easy solutions here. For now, as a fix to be able to
> backport, would you like me to respin this without the change to
> kvm_has_s1poe(), or with that change as a separate patch?

I'll remove the hunk myself when applying the series, no need to
resend (unless I find another issue in the rest of the series, but it
looks good so far).

FWIW, I have an alternative set of hacks at [1], which appear to work,
but we need to collectively convince ourselves that this is the
correct thing to do (i.e. the required traps are always set,
irrespective of the configuration).

This affects PAuth, SVE, MTE and S1POE. SME and GCS are not supported
in KVM, and BTI has no additional state, so these shouldn't be
affected.

Thanks,

	M.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=arm64/ftr_config

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