From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755053AbYHYMdn (ORCPT ); Mon, 25 Aug 2008 08:33:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753577AbYHYMdf (ORCPT ); Mon, 25 Aug 2008 08:33:35 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:45912 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753449AbYHYMde (ORCPT ); Mon, 25 Aug 2008 08:33:34 -0400 Date: Mon, 25 Aug 2008 13:16:20 +0100 From: Alan Cox To: Sitsofe Wheeler Cc: linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org Subject: Re: Reproducible rRootage segfault with 2.6.25 and above (regression?) Message-ID: <20080825131620.1d6aa87f@lxorguk.ukuu.org.uk> In-Reply-To: References: X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.11; x86_64-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > The issue is fiddly but reproducible. All help in pinpointing the > problem source is appreciated. For the kernel bisect if you get stuck at a point it fails remember that point and then lie either yes/no to it working and carry on. If need be you can go back the other way. Another completely off the wall guess would be that your client code is causing gcc to generate something where it is using data which has ended up below the stack pointer and the timings have changed. Either through gcc bug or passing around the address of an object that is out of context. At that point a signal will rewrite the data in fun ways producing results like you describe. Alan