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Date: Thu, 16 Mar 2006 16:50:08 -0800 (PST)
From: Christoph Lameter <clameter@sgi.com>
To: Hugh Dickins <hugh@veritas.com>
cc: linux-kernel@vger.kernel.org, akpm@osdl.org
Subject: Re: Race in pagevec_strip?
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On Thu, 16 Mar 2006, Hugh Dickins wrote:

> On Thu, 16 Mar 2006, Hugh Dickins wrote:
> > 
> > I can't see what protects the default drop_buffers case against this,
> > so can't argue that it's an XFS problem.
> 
> But I should add, I don't see what might be racing with what on the
> same page, to cause the problem in practice.

The page is on the inactive list at the time pagevec_strip is called 
(see refill_inactive_zone). So kswapd could get to it. Could filesystems 
get to the page via the mapping?