Re: [PATCH 05/11] x86/fpu: set PKRU state for kernel threads

From: Sebastian Andrzej Siewior
Date: Thu Oct 18 2018 - 17:24:31 EST


On 2018-10-18 13:56:24 [-0700], Dave Hansen wrote:
> > But this is not the only loophole: There is ptrace interface which is
> > used by gdb (just checked) and also bypasses PKRU. Soâ
>
> Bypassing protection keys is not a big deal IMNHO. In places where a
> sane one is not readily available, I'm totally fine with just
> effectively disabling it (PKRU=0) for the length of time it isn't available.

Okay, this makes things easier. Let document that for kernel threads we
use PKRU=0. This should be happening in my try right now. I double check
tomorrow just in caseâ

Sebastian