From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753993Ab0BVP2j (ORCPT ); Mon, 22 Feb 2010 10:28:39 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:43427 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753857Ab0BVP2h (ORCPT ); Mon, 22 Feb 2010 10:28:37 -0500 Date: Mon, 22 Feb 2010 10:28:36 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Anssi Hannula cc: Oliver Neukum , Matthew Garrett , , , , Subject: Re: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang In-Reply-To: <201002220121.53882.anssi.hannula@iki.fi> Message-ID: MIME-Version: 1.0 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 Mon, 22 Feb 2010, Anssi Hannula wrote: > > > If I additionally insert a one-second delay before the fd is closed, I > > > get this usbmon log: > > > http://stuff.onse.fi/gobi2000/gobi-regression5.mon.log > > > > > > The firmware upload is still unsuccessful. > > > > If I use the option driver instead of qcserial, the firmware upload is > > always successful (without any added delays needed). The usbmon log for > > that case can be found here: > > http://stuff.onse.fi/gobi2000/gobi-regression6.mon.log > > I installed 2.6.31.12 to get a usbmon log with qcserial before the regression > as well (without delays, upload successful): > http://stuff.onse.fi/gobi2000/gobi-regression7.mon.log The major difference between the logs is in the way the data get divided up into packets. In both the successful logs, there are sequences of bulk-OUT packets with lengths like: 44, 1, 15, 1, 13 where the unsuccessful transfer just has a single packet of length 74. Also, the successful transfers show a lot of bulk-IN traffic where the unsuccessful transfer doesn't have any. I don't know if that is relevant, however. No other differences stand out. Alan Stern