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Date: Fri, 24 Sep 2010 10:45:09 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Jeremy Fitzhardinge <jeremy@goop.org>
cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Potential race in irq_chip_set_defaults()?
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Jeremy

On Thu, 23 Sep 2010, Jeremy Fitzhardinge wrote:

>  irq_chip_set_defaults() modifies the irq_chip structure in-place when
> setting up an irq.  If that happens on multiple CPUs at once then it
> could leave the irq_chip structure in an inconsistent state.
> 
> Is there anything preventing that case from happening?  There's no
> locking, and as far as I know there's no rule forbidding concurrent
> calls to set_irq_chip()/irq_chip_set_defaults().

that's true. Never thought about that. Will have a look.

Thanks,

	tglx