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Date: Mon, 20 Dec 2010 21:54:32 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Jesper Juhl <jj@chaosbits.net>
Cc: linux-kernel@vger.kernel.org, Oleg Nesterov <oleg@redhat.com>,
        Roland McGrath <roland@redhat.com>, Ingo Molnar <mingo@elte.hu>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [PATCH][RFC] Always unlock 'tasklist_lock' in
 kernel/exit.c::do_wait()
Message-Id: <20101220215432.af5798d5.akpm@linux-foundation.org>
In-Reply-To: <alpine.LNX.2.00.1012202324540.23785@swampdragon.chaosbits.net>
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On Mon, 20 Dec 2010 23:30:38 +0100 (CET) Jesper Juhl <jj@chaosbits.net> wrote:

> The Coverity checker spotted this. I think it has a point, but I'm not 
> intimate with this code so there could be somethingI'm missing.
> 
> It seems that kernel/exit.c::do_wait() does not always release 
> 'tasklist_lock'.

do_wait_thread() and ptrace_do_wait() will have released tasklist_lock
if they returned non-zero.