From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261868AbTKCKEx (ORCPT ); Mon, 3 Nov 2003 05:04:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261953AbTKCKEx (ORCPT ); Mon, 3 Nov 2003 05:04:53 -0500 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:57614 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S261868AbTKCKEw (ORCPT ); Mon, 3 Nov 2003 05:04:52 -0500 Date: Mon, 3 Nov 2003 10:04:49 +0000 From: Russell King To: Bradley Chapman Cc: "Randy.Dunlap" , linux-kernel@vger.kernel.org Subject: Re: What do frame pointers do? Message-ID: <20031103100449.A22719@flint.arm.linux.org.uk> Mail-Followup-To: Bradley Chapman , "Randy.Dunlap" , linux-kernel@vger.kernel.org References: <20031102204556.0c5b377a.rddunlap@osdl.org> <20031103092909.4955.qmail@web40907.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20031103092909.4955.qmail@web40907.mail.yahoo.com>; from kakadu_croc@yahoo.com on Mon, Nov 03, 2003 at 01:29:09AM -0800 X-Message-Flag: Your copy of Microsoft Outlook is vulnerable to viruses. See www.mutt.org for more details. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 03, 2003 at 01:29:09AM -0800, Bradley Chapman wrote: > > Frame pointers enable more deterministic back tracing of the stack, > > which can be helpful for tracking down bugs. I build with > > CONFIG_FRAME_POINTER enabled all of the time. On ARM, simply scanning the kernel stack for addresses in the kernels text segment or a module text tends to (or at least used to) return a large quantity of noise. This makes reading the backtrace nearly impossible - not only does it contain real function pointers and return addresses, but also pointers to literal pools and the like. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core