Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751957AbWI3UtD (ORCPT ); Sat, 30 Sep 2006 16:49:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751964AbWI3UtB (ORCPT ); Sat, 30 Sep 2006 16:49:01 -0400 Received: from smtp.osdl.org ([65.172.181.4]:14215 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751935AbWI3UtA (ORCPT ); Sat, 30 Sep 2006 16:49:00 -0400 Date: Sat, 30 Sep 2006 13:47:13 -0700 (PDT) From: Linus Torvalds To: Andi Kleen cc: Eric Rannaud , Linux Kernel Mailing List , Ingo Molnar , Andrew Morton , nagar@watson.ibm.com, Chandra Seetharaman , Jan Beulich Subject: Re: BUG-lockdep and freeze (was: Arrr! Linux 2.6.18) In-Reply-To: <200609302230.24070.ak@suse.de> Message-ID: References: <5f3c152b0609301220p7a487c7dw456d007298578cd7@mail.gmail.com> <200609302230.24070.ak@suse.de> 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: 1246 Lines: 32 On Sat, 30 Sep 2006, Andi Kleen wrote: > > We didn't so far find any bug in the unwinder code itself (ok if you don't > count the performance issue Ingo found) just lots in the annotations and one > bug in the dwarf2 standard. I don't think it matters if it's a bug in the unwinding code or in the data generated for it. It's still a bug in the unwinder. Those bugs have been compiler bugs, manual annotation bugs, and it doesn't _matter_ what kind of bugs. The end result is the same: the unwinder is buggy. > If you kick the people who add more than three levels of callback > to core driver code to get their acts together too that's fine > to me. Unfortunately I don't think that's realistic. So we clearly > need better unwinding. I dispute the "clearly". We didn't have _that_ many problems with just manually filtering out obvious left-overs from some previous callchain. I mean, really: Andi, point me to anything that was a real problem when we had no unwinder at all? Linus - 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/