From mboxrd@z Thu Jan  1 00:00:00 1970
From: Trond Myklebust <trond.myklebust@fys.uio.no>
Subject: Re: [patch] mm: close page_mkwrite races
Date: Wed, 01 Apr 2009 19:33:31 -0400
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Cc: Sage Weil <sage@newdream.net>, npiggin@suse.de,
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To: Andrew Morton <akpm@linux-foundation.org>
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On Wed, 2009-04-01 at 16:02 -0700, Andrew Morton wrote:
> What is "the problem"?  Can we get "the problem"'s description included
> in the changelog?
> 
> The patch is fairly ugly, somewhat costly and makes things (even) more
> complex.    Sigh.

The problem is that currently, pages can be marked as dirty after they
have been written out, or even during writeout.

IOW: the filesystem and the mm no longer agree on the state of the page,
which again triggers issues such as
  http://bugzilla.kernel.org/show_bug.cgi?id=12913

Trond