From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751386Ab3AJJml (ORCPT ); Thu, 10 Jan 2013 04:42:41 -0500 Received: from cantor2.suse.de ([195.135.220.15]:58572 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750800Ab3AJJmk (ORCPT ); Thu, 10 Jan 2013 04:42:40 -0500 From: Oliver Neukum To: Laurent Pinchart Cc: Josh Boyer , Alan Stern , gregkh@linuxfoundation.org, mdharm-usb@one-eyed-alien.net, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: USB autosuspend vs. URB submission Date: Thu, 10 Jan 2013 10:42:37 +0100 Message-ID: <1643419.R9VmOAX4j3@linux-5eaq.site> Organization: SUSE User-Agent: KMail/4.8.5 (Linux/3.4.11-2.16-desktop; KDE/4.8.5; x86_64; ; ) In-Reply-To: <2664900.viczl5BYBS@avalon> References: <20130107204220.GB12363@hansolo.jdub.homelinux.org> <20130108160321.GC12363@hansolo.jdub.homelinux.org> <2664900.viczl5BYBS@avalon> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 10 January 2013 00:05:55 Laurent Pinchart wrote: > I've had a quick look at the trace posted at > https://bugzilla.redhat.com/show_bug.cgi?id=879462 but usbmon only shows URBs > that are successfully submitted. I'm not sure what useful information I could > get from the trace. The test is at the very start of usb_submit_urb() if (!urb || !urb->complete) return -EINVAL; if (urb->hcpriv) { WARN_ONCE(1, "URB %p submitted while active\n", urb); return -EBUSY; } usbmon will never see such URBs I suggest that for debugging you change the WARN_ONCE into a WARN and compare the URB pointers of usbmon and dmesg. In the long run it is probably a good idea to pass duplicated URBs to usbmon by a special code path. Regards Oliver