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Subject: Re: [PATCH v3] x86: treat pkey-0 special
To:     Thomas Gleixner <tglx@linutronix.de>, Ram Pai <linuxram@us.ibm.com>
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From:   Dave Hansen <dave.hansen@intel.com>
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Date:   Thu, 15 Mar 2018 08:55:31 -0700
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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.