Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759927AbXKUQbY (ORCPT ); Wed, 21 Nov 2007 11:31:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755103AbXKUQbQ (ORCPT ); Wed, 21 Nov 2007 11:31:16 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:46711 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754581AbXKUQbP (ORCPT ); Wed, 21 Nov 2007 11:31:15 -0500 Date: Wed, 21 Nov 2007 11:31:13 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Markus Rechberger cc: Oliver Neukum , Laurent Pinchart , Mark Lord , , Subject: Re: [linux-usb-devel] USB deadlock after resume In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1420 Lines: 37 On Wed, 21 Nov 2007, Markus Rechberger wrote: > > > it's not just usb_set_interface that hangs actually. > > > It seems to hang at > > > > > > wait_event(usb_kill_urb_queue, atomic_read(&urb->use_count) == 0); > > > > > > in drivers/usb/core/urb.c after resuming. I disabled access to the usb > > > subsystem in the uvc driver, although connecting any other usb storage > > > fails too, just at the same point. > > > > Which URB is usb_kill_urb() called for? > > > > it's the usb_control_message which calls usb_kill_urb if I haven't got > it wrong. (if you're looking for some other information please let me > know) > Although, I got a bit further with it. The error seems to happen > earlier already. > If I load the driver, and do not access the device after suspending > all usb_control commands fail with -71 eproto. That's very strange. Getting -71 errors is understandable; it indicates that the device can't handle being suspended. But the wait_event() line still shouldn't hang. If it does, it indicates that there's something wrong with the USB host controller, not just the device. Can you try testing this on a different sort of computer? Alan Stern - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/