From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751346AbXBVRdM (ORCPT ); Thu, 22 Feb 2007 12:33:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751385AbXBVRdL (ORCPT ); Thu, 22 Feb 2007 12:33:11 -0500 Received: from adsl-70-250-156-241.dsl.austtx.swbell.net ([70.250.156.241]:59550 "EHLO gw.microgate.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751346AbXBVRdL (ORCPT ); Thu, 22 Feb 2007 12:33:11 -0500 Message-ID: <45DDD395.1050502@microgate.com> Date: Thu, 22 Feb 2007 11:32:05 -0600 From: Paul Fulghum User-Agent: Thunderbird 1.5.0.8 (Windows/20061025) MIME-Version: 1.0 To: Jose Goncalves , Frederik Deweerdt , akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: Serial related oops References: <20070219143520.GB27370@flint.arm.linux.org.uk> <20070220144814.GJ566@slug> <20070219150508.GD27370@flint.arm.linux.org.uk> <45D9D073.7020701@inov.pt> <20070219164200.GF27370@flint.arm.linux.org.uk> <45D9E46C.4030408@inov.pt> <20070219212347.GA4258@flint.arm.linux.org.uk> <45DC537B.6020108@inov.pt> <20070221230503.GA28156@flint.arm.linux.org.uk> <45DDB096.2020807@inov.pt> <20070222170354.GB633@flint.arm.linux.org.uk> In-Reply-To: <20070222170354.GB633@flint.arm.linux.org.uk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 22, 2007 at 03:02:46PM +0000, Jose Goncalves wrote: > What I find real hard to understand is why a hardware fault happens > always in the same software instruction! I would expect a hardware fault > to hit randomly... I've experienced just such a hardware fault. The Infineon DSCC4 serial controller has a hardware bug in the PCI request/grant handling that can lead to the device driving the PCI bus in conflict with another device. While the results were random (as the oops in this problem seem to be), the trigger was always activating certain devices in combination. In your case, altering the timing/behavior of the serial device during open may be provoking the hardware fault. -- Paul Fulghum Microgate Systems, Ltd.