Re: [PATCH] x86/shstk: Provide kernel command line knob to disable

[Edgecombe, Rick P]

On Thu, 2026-04-02 at 18:04 +0200, Peter Zijlstra wrote:
> > However, in at least one case the UEFI firmware was involved and I
> > had to test&debug on bare metal. Having such a knob allows ruling
> > out or pin-pointing CET as the cause more easily.
> 
> Fair enough, although this should probably have made it in the
> Changelog.
> 
> Other than that, 

Some firmwares use supervisor shadow stack in SMM and have had issues
with CR4.CET set. But these were BIOS crashes.

The other usefulness could be recovering from shadow stack crashes in
early userspace that block boot.

Acked-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>

Could we add something to the docs though?