Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754836AbZGJOpM (ORCPT ); Fri, 10 Jul 2009 10:45:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752244AbZGJOpA (ORCPT ); Fri, 10 Jul 2009 10:45:00 -0400 Received: from mail.gmx.net ([213.165.64.20]:41904 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751964AbZGJOo7 (ORCPT ); Fri, 10 Jul 2009 10:44:59 -0400 X-Authenticated: #23875046 X-Provags-ID: V01U2FsdGVkX18mZVYfnJcm0c+wtLaQ9U6F53sNANo+Q+rQFDwY8T 114CZ4ntErS0ag Message-ID: <4A5753E8.9040704@fisher-privat.net> Date: Fri, 10 Jul 2009 16:44:56 +0200 From: Alexey Fisher User-Agent: Thunderbird 2.0.0.22 (X11/20090616) MIME-Version: 1.0 To: Thomas Gleixner CC: Ingo Molnar , Matthew Garrett , "H. Peter Anvin" , Arjan van de Ven , "Pallipadi, Venkatesh" , Yinghai Lu , Suresh Siddha , "Rafael J. Wysocki" , Andrew Morton , Linus Torvalds , Linux Kernel Mailing List , Kernel Testers List , "Richard A. Holden III" Subject: Re: Intel BIOS - Corrupted low memory at ffff880000004200 References: <4A5210A2.2080301@fisher-privat.net> <4A52254F.8080103@fisher-privat.net> <20090708113949.GA8960@srcf.ucam.org> <20090710115238.GA8812@elte.hu> <4A573131.40601@fisher-privat.net> In-Reply-To: X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 X-FuHaFi: 0.51 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2275 Lines: 58 Thomas Gleixner schrieb: > On Fri, 10 Jul 2009, Alexey Fisher wrote: >> Ingo Molnar schrieb: >>> * Matthew Garrett wrote: >>> >>>> On Mon, Jul 06, 2009 at 06:24:47PM +0200, Alexey Fisher wrote: >>>>> Hallo Ingo, Richard. >>>>> >>>>> I'm getting "Corrupted low memory" trace with my Intel DG45ID board >>>>> after resume. This board has different dmi-bios-vendor... so probably it >>>>> will be nice to have it in your patch. >>>> I'm beginning to think that we should be doing this on all hardware, >>>> perhaps with a kernel option to disable it for embedded devices that >>>> really need that 64K. The low-memory corruption issue seems to be very >>>> widespread. >>> The problem is that the BIOS corrupted memory that it also marked as >>> 'usable' in its E820 map it gave to the kernel. If that memory is not >>> usable, it should not have been marked as such. Also, some of the reports >>> showed corruption beyond this range so the workaround is not universal. >>> >>> So i'd really like to know what is happening there, instead of just zapping >>> support for 64K of RAM on the majority of Linux systems. >>> >>> We might end up doing the same thing in the end (i.e. disable that 64k of >>> RAM) - but it should be an informed decision, not a wild stab in the dark. >>> >>> Ingo >> If i make memory dump like "dd if=/dev/mem of=memdump.dd bs=64k count=1" >> before and after suspend. Will it help you find out whats happening. > > The corrupted low memory printks contain the modifications. Can you > post them please ? > > Thanks, > > tglx I dumped all between 0000000 - 00ffff0 and there is changes at: 0004200 -> this know one 003c000 - 003fff0 -> this was empty and now it looks like VBIOS 00d18a0 -> i don't know cat /proc/iomem 00000000-0000ffff : reserved 00010000-0009e7ff : System RAM 0009e800-0009ffff : reserved 000e0000-000fffff : reserved 00100000-bd90dfff : System RAM 01000000-014b1f1b : Kernel code 014b1f1c-0171265f : Kernel data 01794000-01842c07 : Kernel bss ..... -- 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/