Re: [PATCH] x86/fpu: Correct pkru/xstate inconsistency

[Dave Hansen]

On 2/15/22 08:19, Brian Geffon wrote:
> This only applies before 5.13, so 5.10.y and 5.4.y, the behavior
> decoupled PKRU from xstate in a long series from Thomas Gleixner, but
> the first commit where this would have been fixed in 5.13 would be:
> 
>   commit 954436989cc550dd91aab98363240c9c0a4b7e23
>   Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>   Date:   Wed Jun 23 14:02:21 2021 +0200
> 
>     x86/fpu: Remove PKRU handling from switch_fpu_finish()

Could you also describe why the >=5.13 fix for this isn't suitable for
older kernels?