From mboxrd@z Thu Jan  1 00:00:00 1970
From: Colin Leroy <colin@colino.net>
Subject: Re: [PATCH] Prevent netpoll hanging when link is down
Date: Mon, 11 Oct 2004 22:45:42 +0200
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Cc: Andi Kleen <ak@suse.de>, "David S. Miller" <davem@davemloft.net>,
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To: Matt Mackall <mpm@selenic.com>
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On 11 Oct 2004 at 11h10, Matt Mackall wrote:

Hi, 

> Ergh, you deleted the context. Again, imagine we're originally in
> ->poll() for _a non-netpoll-related reason_. In other words, the
> console sem is not taken, because we're just doing routine network
> I/O. While in poll(), we take a private driver lock. Then for whatever
> reason, we printk -> netconsole -> netpoll -> poll() again where we
> attempt to retake the private driver lock.
> 
> > P.S.: I made the same mistake long ago, but akpm set me straight.
> 
> I'm pretty sure this case is different.

I tried replacing spin_lock by spin_trylock in poll() and a few other
functions (and returning accordingly), but it didn't help. I'm beginning
to think I won't be able to debug this one! ;)

-- 
Colin
  "When in doubt, do the right thing."