From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753727AbXLCNar (ORCPT ); Mon, 3 Dec 2007 08:30:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751789AbXLCNak (ORCPT ); Mon, 3 Dec 2007 08:30:40 -0500 Received: from public.id2-vpn.continvity.gns.novell.com ([195.33.99.129]:48037 "EHLO public.id2-vpn.continvity.gns.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751454AbXLCNaj convert rfc822-to-8bit (ORCPT ); Mon, 3 Dec 2007 08:30:39 -0500 Message-Id: <4754132B.76E4.0078.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0.2 HP Date: Mon, 03 Dec 2007 13:31:07 +0000 From: "Jan Beulich" To: , , Cc: , , , , , Subject: Re: x86: optimize page faults like all other achitectures and kill notifier cruft Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ever since I started to try to get at least some fundamental infrastructure pieces merged for using NLKD on Linux I was told that direct calls out of exception handlers for the sake of an individual (and perhaps even small) sub-system is undesirable. Making the exception notifiers report the right (correct) information (and, specific to x86, ensuring they get called in the right place) was one of the fundamental things, and just now I see that this is being reverted for (in my eyes) no good reason: Instead of adding direct calls to x86, all the other architectures should have followed the notifier model in order for the infrastructure to be usable by external components, especially if these aren't allowed into the kernel. Am I to conclude that replacing direct calls elsewhere in the tree (in order to e.g. avoid all kinds of small sub-components leaving their footprint in core files like kernel/fork.c) is no longer a desirable goal, thereby making it almost impossible to ever host a kernel debugger *without* having to patch core files. Thanks, Jan