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Date: Wed, 10 Sep 2014 15:00:17 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Toshi Kani <toshi.kani@hp.com>
CC: Andy Lutomirski <luto@amacapital.net>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Juergen Gross <jgross@suse.com>,
        Stefan Bader <stefan.bader@canonical.com>,
        Henrique de Moraes Holschuh <hmh@hmh.eng.br>,
        Yigal Korman <yigal@plexistor.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH v2 2/6] x86, mm, pat: Change reserve_memtype() to handle
 WT
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On 09/10/2014 02:47 PM, Toshi Kani wrote:
>>
>> Yes.  Don't think of it as PAT vs non-PAT.  Think of it as a specific
>> set of cache types available on different processors.  The fact that you
>> may have to frob an MSR to initialize it is almost trivial in comparison.
> 
> Right.
> 

In that sense the Xen "fixed PAT" fits right in.

	-hpa