Re: [PATCH v10 03/15] x86/alternatives: Disable LASS when patching kernel alternatives

From: Peter Zijlstra

Date: Wed Oct 22 2025 - 06:23:22 EST


On Wed, Oct 22, 2025 at 11:40:19AM +0200, Borislav Petkov wrote:

> > But that's not the same, stac() and clac() are FEATURE_SMAP, these are
> > FEATURE_LASS.
>
> So?

That's confusing. Just keep them separate alternatives.

> Are you thinking of toggling features and then something else getting disabled
> in the process?

I'm thinking that machines without LASS don't need the clac/stac in
these places. And when reading the asm, the FEATURE_LASS is a clue.