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Date: Wed, 2 Apr 2003 15:52:20 -0800
From: Andrew Morton <akpm@digeo.com>
To: Dave McCracken <dmccr@us.ibm.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2.5.66-mm2] Fix page_convert_anon locking issues
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Dave McCracken <dmccr@us.ibm.com> wrote:
>
> 
> Oops.  The pmd_present() check should be after the page_to_pfn() !=
> pte_pfn() check.
> 

hmmmm.  It also probably needs both compiler barriers and memory barriers.

It does give me creepy feelings.  I worry that because nobody uses
remap_file_pages() yet, we will hit 2.6.25 before discovering that we have
fundamental VM locking problems which affect $major$ applications.