From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Date: Sat, 13 Nov 2010 12:57:58 +0000
Subject: Re: [BUG 2.6.27-rc1] find_busiest_group() LOCKUP
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To: Wu Fengguang <fengguang.wu@intel.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>, Nikanth Karthikesan <knikanth@suse.de>, Yinghai Lu <yinghai@kernel.org>, David Rientjes <rientjes@google.com>, "Zheng, Shaohui" <shaohui.zheng@intel.com>, Andrew Morton <akpm@linux-foundation.org>, "linux-hotplug@vger.kernel.org" <linux-hotplug@vger.kernel.org>, Eric Dumazet <eric.dumazet@gmail.com>, Bjorn Helgaas <bjorn.helgaas@hp.com>, Venkatesh Pallipadi <venki@google.com>, Nikhil Rao <ncrao@google.com>, Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>

On Sat, 2010-11-13 at 20:00 +0800, Wu Fengguang wrote:
> On Sat, Nov 13, 2010 at 06:30:24PM +0800, Peter Zijlstra wrote:
> > On Sat, 2010-11-13 at 16:40 +0800, Wu Fengguang wrote:
> > > > Will try and figure out how the heck that's happening, Ingo any clue?
> > > 
> > > It's back to normal on 2.6.37-rc1 when reverting commit 50f2d7f682f9
> > > ("x86, numa: Assign CPUs to nodes in round-robin manner on fake NUMA").
> > > 
> > > The interesting part is, the commit was introduced in 
> > > 2.6.36-rc7..2.6.36, however 2.6.36 boots OK, while 2.6.37-rc1 panics.
> > 
> > Argh, that commit again..
> > 
> > Does this fix it: http://lkml.org/lkml/2010/11/12/8
> 
> No it still panics. Here is the dmesg.

OK, I'll let Nikanth have a look, if all else fails we can always revert
that patch.