Date: Wed, 20 Jan 2010 16:45:56 -0500
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>,
       linux-kernel@vger.kernel.org, linux-geode@lists.infradead.org,
       linux-usb@vger.kernel.org, linux-pci@vger.kernel.org
Subject: Re: Strange EHCI/OHCI IRQ and other PCI errors on boot with 2.6.32
	(which 2.6.26 did not see) on Geode LX/CS5536.
Message-ID: <20100120214556.GP24305@caffeine.csclub.uwaterloo.ca>
References: <20100120200125.GO24305@caffeine.csclub.uwaterloo.ca> <Pine.LNX.4.44L0.1001201515520.1672-100000@iolanthe.rowland.org>
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From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen)
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On Wed, Jan 20, 2010 at 03:20:46PM -0500, Alan Stern wrote:
> Okay, this means that something else is affecting the IRQ line.

Yep.  I went and disabled irq5 on the LPC bus, and that didn't help.

> > Interestingly the number of interrupts listed in /proc/interrupts is
> > exactly 300000.
> 
> That's probably because the kernel disabled the IRQ after 100000 
> unhandled interrupts, and re-enabled it each time a new device was
> registered for that IRQ.

Certainly seems to be the case.

> Or you could just stop using USB on the old box.  :-)

Well I just tried another box, and same thing.

If I boot with 'irqpoll' then everything seems fine.

Any idea how I can figure out why irqpoll makes it happy?  Does it give
any reports anywhere about misrouted irqs?

-- 
Len Sorensen
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