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Subject: Re: preempt crash in 2.6.18
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Vitaly Bordug <vbordug@ru.mvista.com>
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Date: Sat, 14 Oct 2006 09:14:38 +1000
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On Sat, 2006-10-14 at 01:21 +0400, Vitaly Bordug wrote:
> On Fri, 13 Oct 2006 09:16:52 -0500
> Rune Torgersen wrote:
> 
> > 
> > This is from a Freescale 8265 running 2.6.18
> > Anyone have any idea what this is and how to fix it?
> > 
> Yes. Actually, I recall alike thing and used to fix with proper spin-locking if the 
> cascade PCI irq, which apparently does do_irq that seems to confuse preempt counters.
> 
> Just a pure guess.

How so ? Cascades shouldn't do do_IRQ with the new irq code anyway
unless this is still arch/ppc, they should do either __do_IRQ or better,
generic_handle_irq().

Ben.