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Date: Fri, 4 Mar 2005 16:31:53 -0800
From: Andrew Morton <akpm@osdl.org>
To: pbadari@us.ibm.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] 2.6.11-mm1 "nobh" support for ext3 writeback mode
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Andrew Morton <akpm@osdl.org> wrote:
>
> page reclaim can come in, grab the page lock and
> whip the page off the mapping.

No it can't - we hold an additional ref on the page, so reclaim will back
off.  Still, it feels a bit flakey.

And we're not supposed to take lock_page() inside journal_start, because
that's a ranking violation.  Probably i_sem will prevent an actual deadlock
occurring, however.