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Subject: Re: [PATCH 2.6.28-rc5 03/11] kmemleak: Add the memory
	allocation/freeing hooks
From: Catalin Marinas <catalin.marinas@arm.com>
To: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: linux-kernel@vger.kernel.org, Matt Mackall <mpm@selenic.com>,
       Christoph Lameter <cl@linux-foundation.org>
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Organization: ARM Ltd
Date: Mon, 24 Nov 2008 10:43:43 +0000
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On Mon, 2008-11-24 at 12:35 +0200, Pekka Enberg wrote:
> On Mon, 2008-11-24 at 10:18 +0000, Catalin Marinas wrote:
> > My understanding is that the ->s_mem value points to the slab itself but
> > the same pointer might actually be the beginning of an allocated memory
> > block, hence we get at least one reference to this block.
> 
> Yes, ->s_mem points to the first object in the slab if CONFIG_DEBUG_SLAB
> is disabled.
> 
> So if I understood this right, in case the first object in the slab is
> leaked (it's allocated but no one references to it), we want to make
> sure kmemleak doesn't see the ->s_mem link which would cause a false
> negative (i.e. a leak that is not reported).
> 
> Did I get it correct this time?

Yes.

-- 
Catalin