Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763454AbYHFDIc (ORCPT ); Tue, 5 Aug 2008 23:08:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751018AbYHFDIY (ORCPT ); Tue, 5 Aug 2008 23:08:24 -0400 Received: from one.firstfloor.org ([213.235.205.2]:48182 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751173AbYHFDIX (ORCPT ); Tue, 5 Aug 2008 23:08:23 -0400 To: Nick Piggin Cc: jmerkey@wolfmountaingroup.com, "Geert Uytterhoeven" , "Stefan Richter" , "Josh Boyer" , linux-kernel@vger.kernel.org Subject: Re: [ANNOUNCE] Merkey's Kernel Debugger From: Andi Kleen References: <17494.166.70.238.46.1217784156.squirrel@webmail.wolfmountaingroup.com> <33030.166.70.238.45.1217948565.squirrel@webmail.wolfmountaingroup.com> <200808060133.10457.nickpiggin@yahoo.com.au> Date: Wed, 06 Aug 2008 05:08:20 +0200 In-Reply-To: <200808060133.10457.nickpiggin@yahoo.com.au> (Nick Piggin's message of "Wed, 6 Aug 2008 01:33:10 +1000") Message-ID: <87r6926dsr.fsf@basil.nowhere.org> User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2271 Lines: 48 Nick Piggin writes: > > Seriously? Because it doesn't seem to have had enough peer review, > it hasn't had widespread testing in somewhere like linux-next or > -mm, and we already have kgdb so you have to also explain why you > can't improve kgdb in the areas it trails mdb. > > But the ideal outcome would be if you could contribute patches to > kgdb to the point where it is as good as mdb. It is already in the I don't think kgdb and a simple assembler debugger are directly comparable. kgdb always requires a remote machine, which has many advantages, but is also often very inconvenient or impossible to arrange. An low overhead assembler debugger can be always compiled in just in case. Also at least for the x86 port the debugger interfaces should be general enough now (see die hooks as a "debug vfs") that it would be quite possible to have a multitude of debuggers just using them. In fact that's already the cases, kprobes and kgdb and kdump are all kinds of debuggers using such hooks. As long as it doesn't impact the core code and the mdb code itself is considered merge worthy and has clean interfaces that would seem fine to me.It essentially would just live somewhere in its own directory using the existing interfaces. My standard test for seeing if a debugger has clean interfaces is to see if it can be loaded as a module. There are enough different debugging styles around that offering developers different tools of which they can pick whatever suits them is not a bad idea. Also as everyone knows debugging is often a major time eater and if more tools are available that can only help the kernel. That said I haven't read the mdb code, not judging on its general merge-worthiness or am really completely sure what are all the details of a "netware style debugger", just a general high level comment on debuggers. At least judging based on the patch sizes it at least doesn't seem particularly bloated. But of course it would need full proper review first. -Andi -- 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/