Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933026Ab1CWPEu (ORCPT ); Wed, 23 Mar 2011 11:04:50 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:40680 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932625Ab1CWPEs (ORCPT ); Wed, 23 Mar 2011 11:04:48 -0400 Date: Wed, 23 Mar 2011 11:04:47 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Herbert Poetzl cc: linux-kernel@vger.kernel.org, Bernhard Kaindl , Andi Kleen , Subject: Re: debugging a modern laptop ... In-Reply-To: <20110323034214.GC15541@MAIL.13thfloor.at> 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 Content-Length: 1195 Lines: 32 On Wed, 23 Mar 2011, Herbert Poetzl wrote: > > Greetings! > > I'm trying to evaluate my options on debugging a recent > laptop/notebook/table (and the Linux kernel on it of course) > from early bootup to diagnostics when the machine has locked > up ... > > normally the first thing I would do is to attach a serial > console to monitor the early bootup and have some way to > send sysrq triggers ... but here is the first problem, > the thing might not even have a serial port at all ... > > most modern devices have at least one usb port, but as far > as I could figure out via google, there is no support for > console or similar over usb (serial or not) atm > (please feel free to correct me here :) There _is_ support for a USB console (see CONFIG_USB_SERIAL_CONSOLE). However it may not be useful for diagnosing problems during boot, because obviously the console won't operate until the USB stack is in place and running. 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/