Re: [PATCH v5 26/39] x86: Introduce userspace API for shadow stack

On Thu, Jan 19, 2023 at 01:23:04PM -0800, Rick Edgecombe wrote:

From: "Kirill A. Shutemov" <redacted>

Add three new arch_prctl() handles:

 - ARCH_SHSTK_ENABLE/DISABLE enables or disables the specified
   feature. Returns 0 on success or an error.

 - ARCH_SHSTK_LOCK prevents future disabling or enabling of the
   specified feature. Returns 0 on success or an error

The features are handled per-thread and inherited over fork(2)/clone(2),
but reset on exec().

This is preparation patch. It does not implement any features.

Tested-by: Pengfei Xu <redacted>
Tested-by: John Allen <john.allen@amd.com>
Signed-off-by: Kirill A. Shutemov <redacted>

Reviewed-by: Kees Cook <redacted>

-- 
Kees Cook