[PATCH 1/3] arm64/fpsimd: ptrace: Fix SVE writes on !SME systems

[Mark Brown]

On Tue, Jan 20, 2026 at 02:51:05PM +0000, Mark Rutland wrote:

> Fix this by removing the system_supports_sme() check. This ensures that
> TIF_SVE is set for (SVE-formatted) writes to NT_ARM_SVE, at the cost of
> unconditionally manipulating the tracee's saved svcr value. The
> manipulation of svcr is benign and inexpensive, and we already do
> similar elsewhere (e.g. during signal handling), so I don't think it's
> worth guarding this with system_supports_sme() checks.

This is much more sensible, IIRC this switch statement was doing
something more expensive in some older out of tree version but now
there's no need for the guard:

Reviewed-by: Mark Brown <broonie at kernel.org>
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