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From: Oliver Neukum <oliver@neukum.org>
Organization: NOvell
To: Jiri Kosina <jkosina@suse.cz>
Subject: Re: [PATCH] USB: fix deadlock in HCD code
Date: Wed, 21 May 2008 15:47:45 +0200
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Cc: Greg KH <greg@kroah.com>, linux-usb@vger.kernel.org,
       Alan Stern <stern@rowland.harvard.edu>, lchiquitto@novell.com,
       linux-kernel@vger.kernel.org
References: <Pine.LNX.4.64.0805211405520.6718@jikos.suse.cz> <200805211533.00221.oliver@neukum.org> <Pine.LNX.4.64.0805211533500.6718@jikos.suse.cz>
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Am Mittwoch 21 Mai 2008 15:36:49 schrieb Jiri Kosina:
> On Wed, 21 May 2008, Oliver Neukum wrote:
> 
> > This turns out not to be the case. Interrupts are disabled.
> 
> You're right, this callchain can't cause the deadlock indeed. I'll go 
> through the other possibilities.

usb_hcd_flush_endpoint() is an obvious case. Used in the suspend code.
Your patch is indeed correct, but I fear there might be a second bug caused
by wrong calling conditions.

	Regards
		Oliver