Re: [patch 02/38] x86/cpu: Use native_wrmsrl() in load_percpu_segment()

From: Linus Torvalds
Date: Sun Jul 17 2022 - 11:21:11 EST


On Sat, Jul 16, 2022 at 5:22 PM Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx> wrote:
>
> It's only 32bit where the percpu pointer is tied to the GDT. On 64bit,
> gsbase is good before this, and remains good after.

That sounds sensible to me, but somebody should check that there's
nothing that accidentally relied on the MSR_GS_BASE setting (or the
segment selector clearing, for that matter).

Not that I can necessarily see how anything could work with it wrong, but..

Linus