[PATCH v3] x86: treat pkey-0 special

[Thomas Gleixner]

On Thu, 15 Mar 2018, Dave Hansen wrote:

> On 03/15/2018 02:46 AM, Thomas Gleixner wrote:
> >> +	if (!pkey || !mm_pkey_is_allocated(mm, pkey))
> > Why this extra check? mm_pkey_is_allocated(mm, 0) should not return true
> > ever. If it does, then this wants to be fixed.
> 
> I was thinking that we _do_ actually want it to seem allocated.  It just
> get "allocated" implicitly when an mm is created.  I think that will
> simplify the code if we avoid treating it specially in as many places as
> possible.

That works as well.