From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael Chan" <mchan@broadcom.com>
Subject: Re: tg3 reset_task question
Date: Wed, 04 Apr 2007 14:37:01 -0700
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Cc: netdev@vger.kernel.org
To: "Gagan Arneja" <gaagaan@gmail.com>
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On Wed, 2007-04-04 at 13:34 -0700, Gagan Arneja wrote:
> Can't this BUG_ON be hit very easily:
> 
> static void tg3_irq_quiesce(struct tg3 *tp)
> {
>         BUG_ON(tp->irq_sync);
> ...
> }
> 
> tg3_reset_task could easily be racing with another thread, that calls
> tg3_full_lock(tp, 1); e.g tg3_change_mtu. Maybe I'm missing something
> obvious.
> 

Yes, you're right.  Perhaps we should get the rtnl first before
tg3_full_lock(), or turn irq_sync into an atomic counter that allows
nesting.