From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] bridge: fix race with topology change timer
Date: Fri, 03 May 2013 16:11:37 -0400 (EDT)
Message-ID: <20130503.161137.1979947914410869390.davem@davemloft.net>
References: <20130502172328.2ff0273f@nehalam.linuxnetplumber.net>
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From: Stephen Hemminger <stephen@networkplumber.org>
Date: Thu, 2 May 2013 17:23:28 -0700

> A bridge should only send topology change notice if it is not
> the root bridge. It is possible for message age timer to elect itself
> as a new root bridge, and still have a topology change timer running
> but waiting for bridge lock on other CPU.
> 
> Solve the race by checking if we are root bridge before continuing.
> This was the root cause of the cases where br_send_tcn_bpdu would OOPS.
> 
> Reported-by: JerryKang <jerry.kang@samsung.com>
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>

Applied and queued up for -stable.