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Subject: Re: [PATCH 11/26] x86, pkeys: add functions for set/fetch PKRU
To: Thomas Gleixner <tglx@linutronix.de>
References: <20150916174903.E112E464@viggo.jf.intel.com>
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 <alpine.DEB.2.11.1509222204020.5606@nanos>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
From: Dave Hansen <dave@sr71.net>
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Date: Tue, 22 Sep 2015 13:22:43 -0700
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On 09/22/2015 01:05 PM, Thomas Gleixner wrote:
> On Wed, 16 Sep 2015, Dave Hansen wrote:
>> This adds the raw instructions to access PKRU as well as some
>> accessor functions that correctly handle when the CPU does
>> not support the instruction.  We don't use them here, but
>> we will use read_pkru() in the next patch.
>>
>> I do not see an immediate use for write_pkru().  But, we put it
>> here for partity with its twin.
> 
> So that read_pkru() doesn't feel so lonely? I can't follow that logic.

I was actually using it in a few places, but it fell out of later
versions of the patch.  I'm happy to kill it.