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Subject: Re: sungem hangs in atomic if netconsole enabled but no carrier
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Francois Romieu <romieu@fr.zoreil.com>
Cc: Johannes Berg <johannes@sipsolutions.net>, linux-kernel@vger.kernel.org,
       "David S. Miller" <davem@redhat.com>,
       Eric Lemoine <eric.lemoine@gmail.com>
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Date: Wed, 21 Dec 2005 09:59:14 +1100
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On Tue, 2005-12-20 at 23:19 +0100, Francois Romieu wrote:

> net/core/netpoll.c::netpoll_send_skb() notices that the queue is stopped
> and decides to try the usual NAPI poll(). A few function calls later, the
> driver ends in drivers/net/sungem.c::gem_poll() where it takes so many
> (irq-)locks that I do not even want to verify that it has a chance
> to play nice with the pending gem_link_timer().

I'm not fan of the locking in sungem, I think I wrote a big fat comment
about it and why it is like that for now, better ideas are welcome :)

Ben.