From mboxrd@z Thu Jan  1 00:00:00 1970
From: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Subject: Re: [PATCH] macb: Add support of the netpoll API
Date: Fri, 17 Apr 2009 11:07:03 +0200
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Cc: thomas.petazzoni@free-electrons.com, netdev@vger.kernel.org,
	michael@free-electrons.com
To: David Miller <davem@davemloft.net>
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David Miller wrote:
> And in response to this Haavard explained the potential deadlock
> (sorry I deleted that email) and suggested to use local_irq_save()
> 
> But that won't work either, because it doesn't prevent the interrupt
> handler from running on other cpus, it only prevents that on the
> local cpu.

The interrupt handler takes bp->lock. Isn't that sufficient to prevent
it from running on other cpus?

If you do local_irq_save() around the interrupt handler, the end result
will be identical to spin_lock_irqsave(), which is what the other
(non-interrupt) parts of the driver use.

Or am I misunderstanding something?

Haavard