From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756295AbZKBQ7p (ORCPT ); Mon, 2 Nov 2009 11:59:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756274AbZKBQ7m (ORCPT ); Mon, 2 Nov 2009 11:59:42 -0500 Received: from mail.ihtiyat.org ([212.108.130.11]:2480 "EHLO ebim.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756255AbZKBQ7l (ORCPT ); Mon, 2 Nov 2009 11:59:41 -0500 X-Greylist: delayed 1823 seconds by postgrey-1.27 at vger.kernel.org; Mon, 02 Nov 2009 11:59:40 EST Subject: Faulty MTRR setups in Toshiba laptops crash video drivers From: Mehmet Giritli Reply-To: mehmet@giritli.eu To: linux-kernel@vger.kernel.org Content-Type: text/plain Date: Mon, 02 Nov 2009 18:28:48 +0200 Message-Id: <1257179328.13327.34.camel@frodo.giritli.eu> Mime-Version: 1.0 X-Mailer: Evolution 2.26.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello all, On some laptops using ATI 3650HD radeon chipsets and 4GB ram (and may be others as well), it is impossible to start any xserver due to (faulty?) mtrr setups on the machine. The computer locks up or just gives an unresponsive black screen. There are various drivers for radeon cards and the crash occurs in all of these drivers in the very same way! This bug seems to occur mostly on Toshiba laptops with ATI graphic cards. For some people, CONFIG_MTRR_SANITIZER seemed to cure the issue but made no difference for many others like me. RadeonHD people seem to have problems in understanding the nature of this bug. Please have a look at the threads: http://lists.opensuse.org/radeonhd/2009-05/msg00040.html and, http://bugs.freedesktop.org/show_bug.cgi?id=20645 for problem reports and dev responses. RadeonHD devs suggest that some laptops have weird mtrr setups and this must be fixed in the kernel code and not the driver code. Currently, the only way that could make the driver work is to reduce the 4GB ram to 2GB. dmesg from my affected machine when it has 4GB ram installed can be found here: http://bugzilla.kernel.org/attachment.cgi?id=22856 Also, look at the report here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/341681 in order to see how many people are being affected by this bug! Kind Regards, M. Giritli