Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756735AbXFTW4N (ORCPT ); Wed, 20 Jun 2007 18:56:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752660AbXFTWz6 (ORCPT ); Wed, 20 Jun 2007 18:55:58 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:44324 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751541AbXFTWz5 (ORCPT ); Wed, 20 Jun 2007 18:55:57 -0400 Date: Wed, 20 Jun 2007 15:54:37 -0700 (PDT) From: Linus Torvalds To: Ian McDonald cc: Andrew Morton , LKML , Miklos Szeredi , Ingo Molnar , "Darrick J. Wong" , Andi Kleen , Bj?rn Steinbrink , William Cohen , "S. P. Prasanna" , Antonino Daplas , Olaf Hering , Ville Syrj?l? , Jean Delvare , Rudolf Marek , Soeren Sonnenburg , Michal Piotrowski Subject: Re: [1/2] 2.6.22-rc5: known regressions with patches In-Reply-To: <5640c7e00706201541g3ecaf8c5i524d8b464d8fcc2d@mail.gmail.com> Message-ID: References: <467543FA.60905@googlemail.com> <5640c7e00706201508g3c1fc40eq82a1db05c9156b5d@mail.gmail.com> <5640c7e00706201541g3ecaf8c5i524d8b464d8fcc2d@mail.gmail.com> 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: 1088 Lines: 29 On Thu, 21 Jun 2007, Ian McDonald wrote: > > It depends on the purpose of DEBUG_RODATA. If DEBUG_RODATA was for > security reasons then I agree, but it seems to be more to catch > accidental writes. Well, I'd say that it is *one* tool for debugging. Now, Kprobes is another tool - and I'm just saying that I don't see why you should really expect to break one tool with the other. They take different approaches. And yes, sometimes debugging *does* change what it debugs. In timing, if nothing else, but also in the kinds of things you can do. For example, we don't allow slab redzoning on data structures that have alignment restrictions not compatible with the redzoning, and I'd argue that this is more of the same: we just should not do DEBUG_RODATA if you expect to change read-only data. There's just no *point*. 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/