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Date:   Thu, 15 Mar 2018 17:13:16 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Dave Hansen <dave.hansen@intel.com>
cc:     Ram Pai <linuxram@us.ibm.com>, mingo@redhat.com,
        mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org,
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Subject: Re: [PATCH v3] x86: treat pkey-0 special
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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.