Re: [PATCH v3] x86/cpufeatures: Make X86_FEATURE_SHSTK clearcpuid-able

[Edgecombe, Rick P]

On Thu, 2026-05-14 at 10:30 -0700, Dave Hansen wrote:
> On 5/14/26 10:07, Edgecombe, Rick P wrote:
> > Also, have you ever thought about keeping a list of approved clearcpuid values
> > that are supported for normal runtime. People could use it to turn off features
> > without picking up a taint? 
> 
> What's wrong with taint?
> 
> "I got a bug report from Joe who has a system with feature $FOO and not
> feature $BAR. I don't have that CPU, so I used clearcpuid=$BAR to help
> reproduce the bug. Here's the oops I saw..."
> 
> We're not going to ignore that bug report. We're going to look at it a
> bit closer and make sure the taint does appear to be from
> clearcpuid=$BAR. But the taint is *FINE*.

For debugging I don't see a problem with the taint. But I meant instead of nofoo
for the cases where there is some other purpose. I just thought the clearcpuid
solution was kind of slick compared to nofoo.