From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753847AbXCTUeR (ORCPT ); Tue, 20 Mar 2007 16:34:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753832AbXCTUeR (ORCPT ); Tue, 20 Mar 2007 16:34:17 -0400 Received: from sccrmhc13.comcast.net ([63.240.77.83]:55197 "EHLO sccrmhc13.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753889AbXCTUeQ (ORCPT ); Tue, 20 Mar 2007 16:34:16 -0400 Subject: Re: BSOD From: Jim Gettys Reply-To: jg@laptop.org To: Paul Mackerras Cc: David Miller , jesse.barnes@intel.com, zaitcev@redhat.com, linux-kernel@vger.kernel.org In-Reply-To: <17919.42767.233797.860230@cargo.ozlabs.ibm.com> References: <20070319120807.af36ef5d.zaitcev@redhat.com> <20070319.123836.39155546.davem@davemloft.net> <200703191254.36373.jesse.barnes@intel.com> <20070319.130544.115907938.davem@davemloft.net> <17919.42767.233797.860230@cargo.ozlabs.ibm.com> Content-Type: text/plain Organization: OLPC Date: Tue, 20 Mar 2007 16:33:56 -0400 Message-Id: <1174422836.6832.313.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2007-03-20 at 20:19 +1100, Paul Mackerras wrote: > Anything is better than nothing. At the moment we get nothing if you > are in X when the panic occurs, even for the nicest, most well-behaved > panics. :) If we can change that to getting something sometimes, > that's a win. Treating the display as a frame buffer if at all possible is more likely to work than anything else. All the kernel needs to know is beginning address, stride (# bytes/line; not necessarily the same as the number of pixels on a row), number of rows, and depth of the display. Thereafter, it's just a SMOP as they say (and the sometimes maligned fbdev driver of course already has all this code, and usually oops messages do ok on fbdev). The other interesting headache that comes up sometimes is when the oops message is more than a screen-full long. One may also need to reset lookup tables to some sane value, and halt the GPU, and maybe worry about video overlays. - Jim -- Jim Gettys One Laptop Per Child