Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752214AbZAZH2R (ORCPT ); Mon, 26 Jan 2009 02:28:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751326AbZAZH2A (ORCPT ); Mon, 26 Jan 2009 02:28:00 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:49125 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751296AbZAZH17 (ORCPT ); Mon, 26 Jan 2009 02:27:59 -0500 Date: Sun, 25 Jan 2009 23:27:53 -0800 From: Andrew Morton To: "Thomas Tuttle" Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: System hang (and other problems) with cdc_acm Message-Id: <20090125232753.db40c160.akpm@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1148 Lines: 27 (cc linux-usb) On Mon, 19 Jan 2009 15:20:13 -0500 "Thomas Tuttle" wrote: > Hi. > > I've got a Lenovo X200 with an Ericsson F3507g Mobile Broadband Module > (a 3G cellular data card with built-in GPS), which uses the cdc_acm > driver. I've experienced a couple of problems with it. First, it > tends to hang the system after I've been using it for a while. This > occurs whenever it's sending a lot of data to/from the computer, > whether it's a PPP connection or a GPS data stream. I'm not sure how > to debug this; the Caps Lock light isn't flashing, so I'm not sure if > it's a panic or just a hang. Second, if I read one of the TTYs using > "cat", I get a ton of blank lines. To make any sense of the data > stream, I have to do cat /dev/ttyACM0 | grep -v "^$". > > If anyone could help me debug this, I'd be greatly appreciative. > > Thanks, > > Thomas Tuttle -- 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/