From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: Kernel problem
Date: Thu, 26 Feb 2009 04:10:37 -0800 (PST)
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 26 Feb 2009 19:56:04 +0800

> On Thu, Feb 26, 2009 at 10:56:16AM +0000, Jarek Poplawski wrote:
> > 
> > netconsole. It's a known issue, btw.
> 
> I see.  So the problem in this case appears to be that we're
> processing incoming packets in netpoll_poll.  So the obvious
> question can we just not do that since all we need to do is
> transmit packets?

netpoll supports receiving packets and has a trap handler to eat them
to avoid packets it is interested in going into the real stack.
(netpoll_receive_skb, netpoll_rx_skb, etc.)

I'm pretty sure this has been discussed before. :-)

If I'm not mistaken, we only see this with certain drivers, and the
issue therefore likely has to do with how such drivers implement their
poll handler.

If you do your ->poll_controller() handler without taking IRQ locks,
you're fine.  Or something like that...