From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Re: [PATCH 2/2] Linux support for hugepages as a
	Xen	PV guest
Date: Wed, 15 Oct 2008 14:48:22 -0700
Message-ID: <48F66526.9050807@goop.org>
References: <C515195F.1E0C5%keir.fraser@eu.citrix.com>	<200810101006.44389.dcm@mccr.org>
	<200810151201.06367.dcm@mccr.org>
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To: Dave McCracken <dcm@mccr.org>
Cc: xen-devel@lists.xensource.com, Keir Fraser <keir.fraser@eu.citrix.com>
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Dave McCracken wrote:
> For starters, Xen currently does remove PSE from the CPUID it returns to the 
> guest.  I'll add some code to allow PSE when hugepages are enabled.
>   

Yep.

> Second, in Linux for the x86_64 architecture the macro to check for PSE is 
> hard-wired to always be true.
>   

Not in current kernels.

> Third, hugepages in Linux makes no check whatsoever for the presence or 
> absence of PSE.  It assumes it's there.
>   

Not in current kernels.  But it does assume that if PSE is present, then 
physical memory can always be mapped with large pages.

> I'll look into the simplest way to make the various Linux parts obey the PSE 
> flag properly.
>   

No, use a current mainline git linux kernel.

    J