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Subject: Re: [PATCH] slub: prevent validate_slab() error due to race
 condition
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Don Morris <don.morris@hp.com>
Cc: Waiman Long <Waiman.Long@hp.com>, cl@linux-foundation.org,
        penberg@kernel.org, mpm@selenic.com, linux-mm@kvack.org,
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Date: Thu, 26 Apr 2012 21:44:11 +0200
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On Thu, 2012-04-26 at 12:20 -0700, Don Morris wrote:

> Note that he sets n here, hence the if() block on 2458 can not
> be taken (!n fails) and the if(likely(!n)) is not taken for the
> same reason. As such, the code falls through to the returns for
> either the slab being empty (or not) where the node lock is
> released (2529 / 2543).

Ah yes, you're right, thanks for clarification.