From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
Subject: Re: [PATCH net] openvswitch: fix a possible deadlock and
 lockdep warning
Date: Fri, 28 Mar 2014 16:36:39 -0400 (EDT)
Message-ID: <20140328.163639.788185926435545136.davem@davemloft.net>
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From: Flavio Leitner <fbl-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Date: Thu, 27 Mar 2014 09:53:56 -0300

> There are two problematic situations.
> 
> A deadlock can happen when is_percpu is false because it can get
> interrupted while holding the spinlock. Then it executes
> ovs_flow_stats_update() in softirq context which tries to get
> the same lock.
> 
> The second sitation is that when is_percpu is true, the code
> correctly disables BH only for the local CPU, but that confuses
> lockdep enough to trigger the warning below.
> 
> This patch disables BH for both cases fixing the real deadlock
> and the lockdep warning message.
 ...
> Signed-off-by: Flavio Leitner <fbl-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

I'll let Jesse review and pick this up.