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Date: Thu, 14 Aug 2008 10:46:06 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Fix the race between walk_tg_tree and
	sched_create_group
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> On Wed, 2030-08-14 at 15:56 +0800, Zhang, Yanmin wrote:
> > With 2.6.27-rc3, I hit a kernel panic when running volanoMark on my
> > new x86_64 machine. I also hit it with other 2.6.27-rc kernels.
> > See below log.
> > 
> > Basically, function walk_tg_tree and sched_create_group have a race between
> > accessing and initiating tg->children. Below patch fixes it by moving 
> > tg->children initiation to the front of linking tg->siblings to parent->children.
> > 
> > Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
> 
> Nice catch
> 
> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

applied to tip/sched/urgent - thanks.

	Ingo