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Date: Fri, 30 Dec 2005 01:59:15 +0100
From: Francois Romieu <romieu@fr.zoreil.com>
To: Dave Airlie <airlied@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>, netdev@vger.kernel.org
Subject: Re: spinlock BUG on b44 netconsole
Message-ID: <20051230005915.GA16587@electric-eye.fr.zoreil.com>
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(netdev Cced)

Dave Airlie <airlied@gmail.com> :
[...]

Replace the spinlock in b44_start_xmit by the irq_{save/restore} version.
Do the same around for spin_lock(&np->dev->xmit_lock); in netpoll_send_skb.

If it helps, it's an ugly, buggy, bandaid and you should consider
capturing the messages through a serial cable instead.

If you want to read the details, see the thread "Netconsole violates
dev->hard_start_xmit synch rules" started the 06/09/2005 on
netdev@vger.kernel.org.

--
Ueimor