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Subject: Re: auro deadlock
From: Arjan van de Ven <arjan@infradead.org>
To: David Miller <davem@davemloft.net>
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Date: Fri, 07 Jul 2006 21:39:55 +0200
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On Fri, 2006-07-07 at 12:09 -0700, David Miller wrote:
> From: Arjan van de Ven <arjan@infradead.org>
> Date: Fri, 07 Jul 2006 20:13:09 +0200
> 
> > Now a question for netdev: what is the interrupt-or-softirq rules for
> > the sk_receive_queue.lock?
> > 
> > Anyway, the patch below fixes this deadlock; it may or may not be the
> > correct solution depending on the netdev answer, but the deadlock is
> > gone ;)
> 
> The lockdep fixes are starting to cause us to go in and start adding
> hard IRQ protection to many socket layer objects and I want this
> thinking to end quickly :)

that's why I asked the question ;)


> To reiterate, nothing socket or SKB level should be taking anything
> deeper than software IRQ locking.
> 
> If drivers manage local SKB queues in hard IRQ context, they need to
> use a seperate lockdep identifier for that queue's lock.

I'm not so sure that;s the case here, but.. if you have time today I
hope you can take a look at this one with a wider "network view" than I
can..