From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <amwang@redhat.com>
Subject: Re: [PATCH] net/802/mrp: fix lockdep splat
Date: Tue, 14 May 2013 09:12:20 +0800
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	 <1368447851.13473.119.camel@edumazet-glaptop>
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Cc: Denys Fedoryshchenko <denys@visp.net.lb>,
	David Ward <david.ward@ll.mit.edu>,
	hayeswang <hayeswang@realtek.com>,
	Francois Romieu <romieu@fr.zoreil.com>, netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Mon, 2013-05-13 at 05:24 -0700, Eric Dumazet wrote:
>         del_timer_sync(&app->join_timer);
>  
> -       spin_lock(&app->lock);
> +       spin_lock_bh(&app->lock); 

But we just have removed the join timer before taking this spin lock, so
it is not possible to race with timer, but we still have race condition
with mrp_rcv() which is called in BH context too. However, this is not
what Denys reported, so I have no idea on this.