From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750915AbWDITX1 (ORCPT ); Sun, 9 Apr 2006 15:23:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750917AbWDITX1 (ORCPT ); Sun, 9 Apr 2006 15:23:27 -0400 Received: from khc.piap.pl ([195.187.100.11]:42512 "EHLO khc.piap.pl") by vger.kernel.org with ESMTP id S1750915AbWDITX0 (ORCPT ); Sun, 9 Apr 2006 15:23:26 -0400 To: James Courtier-Dutton Cc: linux list Subject: Re: Black box flight recorder for Linux References: <44379AB8.6050808@superbug.co.uk> From: Krzysztof Halasa Date: Sun, 09 Apr 2006 21:23:16 +0200 In-Reply-To: <44379AB8.6050808@superbug.co.uk> (James Courtier-Dutton's message of "Sat, 08 Apr 2006 12:12:56 +0100") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org James Courtier-Dutton writes: > Now, the question I have is, if I write values to RAM, do any of those > values survive a reset? If any did survive, one could use them to > store oops output in. I am currently only interested in Intel CPU and > AMD CPU based motherboards. If only some values survived, one could > use some sort of redundant encoding so the good values could be > recovered. > > The main advantage of something like this would be for newer > motherboards that are around now that don't have a serial port. Interesting idea. I think the most trivial and reliable way would be to solder some I^2 or similar EEPROM chip to, for example, parallel port connector. Most motherboards have an internal I^2C bus / SMBus (for reading RAM types and for other things) and I think it could be used to connect the EEPROM instead of external port. There are 512 Kbit (64 KB) and 1 Mbit (128 KB) EEPROMs available - there is plenty of space not only for crash dump but for whole dmesg. -- Krzysztof Halasa