From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pekka Enberg <penberg@kernel.org>
Subject: Re: [Bugme-new] [Bug 33502] New: Caught 64-bit read from uninitialized
 memory in __alloc_skb
Date: Mon, 9 May 2011 22:44:18 +0300 (EEST)
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Cc: Christoph Lameter <cl@linux.com>,
	Pekka Enberg <penberg@cs.helsinki.fi>,
	casteyde.christian@free.fr,
	Andrew Morton <akpm@linux-foundation.org>,
	netdev@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org,
	bugme-daemon@bugzilla.kernel.org,
	Vegard Nossum <vegardno@ifi.uio.no>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Wed, 20 Apr 2011, Eric Dumazet wrote:
> [PATCH v4] slub: dont use cmpxchg_double if KMEMCHECK or DEBUG_PAGEALLOC
>
> Christian Casteyde reported a KMEMCHECK splat in slub code.
>
> Problem is now we are lockless and allow IRQ in slab_alloc(), the object
> we manipulate from freelist can be allocated and freed right before we
> try to read object->next.
>
> Same problem can happen with DEBUG_PAGEALLOC
>
> Just dont use cmpxchg_double() if either CONFIG_KMEMCHECK or
> CONFIG_DEBUG_PAGEALLOC is defined.

Christoph, Eric, is this still relevant after commit 1759415 ("slub: 
Remove CONFIG_CMPXCHG_LOCAL ifdeffery") in slab/next of slab.git?

 			Pekka