Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751338AbWI3Vdw (ORCPT ); Sat, 30 Sep 2006 17:33:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751981AbWI3Vdw (ORCPT ); Sat, 30 Sep 2006 17:33:52 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:63926 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751338AbWI3Vdv (ORCPT ); Sat, 30 Sep 2006 17:33:51 -0400 Date: Sat, 30 Sep 2006 23:25:24 +0200 From: Ingo Molnar To: Linus Torvalds Cc: Andi Kleen , Eric Rannaud , Linux Kernel Mailing List , Andrew Morton , nagar@watson.ibm.com, Chandra Seetharaman , Jan Beulich Subject: Re: BUG-lockdep and freeze (was: Arrr! Linux 2.6.18) Message-ID: <20060930212524.GA6332@elte.hu> References: <5f3c152b0609301220p7a487c7dw456d007298578cd7@mail.gmail.com> <200609302230.24070.ak@suse.de> <20060930204900.GA576@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -2.8 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.8 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.5 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.4999] -0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 933 Lines: 26 * Linus Torvalds wrote: > It could - and _should_ dammit! - do some basic sanity tests like "is > the thing even in the same stack page"? But nooo... It seems > _designed_ to be fragile and broken. > > Here's a simple test: if the next stack-slot isn't on the same page, > the unwind information is bogus unless you had the IRQ stack-switch > signature there. Does the code do that? No. It just assumes that > unwind information is complete and perfect. fully agreed - i have pointed out areas of conceptual fragility to Jan early on: http://lkml.org/lkml/2006/6/2/59 (but AFAICS i got no reply to that mail - i missed that in the lockdep flurry.) Ingo - 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/