Re: [PATCH 6/6] x86: Fix stray A/D bit setting into non-present PTEs

From: Linus Torvalds
Date: Fri Jul 01 2016 - 01:50:14 EST


On Thu, Jun 30, 2016 at 9:39 PM, Dave Hansen <dave@xxxxxxxx> wrote:
>
> I think what you suggest will work if we don't consider A/D in
> pte_none(). I think there are a bunch of code path where assume that
> !pte_present() && !pte_none() means swap.

Yeah, we would need to change pte_none() to mask off D/A, but I think
that might be the only real change needed (other than making sure that
we don't use the bits in the swap entries, I didn't look at that part
at all)

Linus