Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 19 Jun 2002 10:38:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 19 Jun 2002 10:38:47 -0400 Received: from delta.ds2.pg.gda.pl ([213.192.72.1]:56455 "EHLO delta.ds2.pg.gda.pl") by vger.kernel.org with ESMTP id ; Wed, 19 Jun 2002 10:38:47 -0400 Date: Wed, 19 Jun 2002 16:35:46 +0200 (MET DST) From: "Maciej W. Rozycki" To: Keith Owens cc: Robbert Kouprie , linux-kernel@vger.kernel.org Subject: Re: The buggy APIC of the Abit BP6 In-Reply-To: <25764.1024495399@ocs3.intra.ocs.com.au> Message-ID: Organization: Technical University of Gdansk 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 Content-Length: 958 Lines: 21 On Thu, 20 Jun 2002, Keith Owens wrote: > You do not have the data required to (a) detect the problem and (b) > recover even if you could detect the problem. The APIC bus has a > single bit checksum, the APIC hardware detects single bit errors and > does a retransmission. It _cannot_ detect double bit errors, the bad > data is accepted and processed with undefined side effects. Thanks to the way the checksum is calculated (a two-bit cumulative sum), about 75% of double-bit errors are detected as well. -- + Maciej W. Rozycki, Technical University of Gdansk, Poland + +--------------------------------------------------------------+ + e-mail: macro@ds2.pg.gda.pl, PGP key available + - 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/