[PATCH v7 02/39] prctl: arch-agnostic prctl for shadow stack

[Edgecombe, Rick P]

On Wed, 2023-11-22 at 09:42 +0000, Mark Brown wrote:
> These features are expected to be inherited by new threads and
> cleared
> on exec(), unknown features should be rejected for enable but
> accepted
> for locking (in order to allow for future proofing).

The reason why I stuck with arch_prctl when this came up is that CRIU
(and probably other ptracers) needs a way to unlock via ptrace. ptrace
arch_prctl() can do this. Did you have a plan for unlocking via ptrace?