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Date: Tue, 22 Jul 2008 12:55:52 +1000
From: Lachlan McIlroy <lachlan@sgi.com>
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Subject: Re: [PATCH] Do not access buffers after dropping reference count
References: <4885430D.7000506@sgi.com> <20080722022404.GH6761@disturbed>
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To: Lachlan McIlroy <lachlan@sgi.com>, xfs-dev <xfs-dev@sgi.com>, xfs-oss <xfs@oss.sgi.com>

Dave Chinner wrote:
> On Tue, Jul 22, 2008 at 12:16:45PM +1000, Lachlan McIlroy wrote:
>> We should not access a buffer after dropping it's reference count otherwise
>> we could race with another thread that releases the final reference count
>> and frees the buffer causing us to access potentially unmapped memory.
> 
> Looks OK. The commit message should point out this is a problem
> only for DEBUG kernels, though.

Okay, will do.