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From: David Brownell <david-b@pacbell.net>
To: Alan Stern <stern@rowland.harvard.edu>
Subject: Re: WARNING: at drivers/usb/host/ehci-hcd.c:287
Date: Tue, 4 Mar 2008 12:51:06 -0800
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Cc: Christian Kujau <lists@nerdbynature.de>,
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On Tuesday 04 March 2008, Alan Stern wrote:
> Dave, it seems to me that this must be an example of a race between the 
> iaa watchdog timer expiring and end_unlink_async() running. ?It's not 
> good enough for end_unlink_async() to call iaa_watchdog_done(), because 
> on an SMP system the timer may already have fired and the watchdog 
> routine may be spinning on ehci->lock.

Right.


> How about replacing the
> 
> ????????WARN_ON(!ehci->reclaim);

Or bettter yet, just removing it entirely.  ISTR doing that in some
patches I've not yet sent for merging, and expect that's what my
preferred fix will be ...

- Dave
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