From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752761AbYIJF7u (ORCPT ); Wed, 10 Sep 2008 01:59:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751288AbYIJF7n (ORCPT ); Wed, 10 Sep 2008 01:59:43 -0400 Received: from terminus.zytor.com ([198.137.202.10]:54568 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751145AbYIJF7m (ORCPT ); Wed, 10 Sep 2008 01:59:42 -0400 Message-ID: <48C76243.5010206@zytor.com> Date: Tue, 09 Sep 2008 22:59:31 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Ingo Molnar CC: heukelum@fastmail.fm, linux-kernel@vger.kernel.org, ak@suse.de Subject: Re: [RFC/PATCH] i386: handle all exceptions with interrupts off initially References: <1220990178-29773-1-git-send-email-heukelum@fastmail.fm> <48C73EB8.8020405@zytor.com> <20080910055337.GA9765@elte.hu> In-Reply-To: <20080910055337.GA9765@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > > the entry paths here are really short (we enable irqs almost > immediately) so it's a non-issue in terms of worst-case latencies. > >> In other words, it's not something we want to do "just because", but >> to the extent that it provides real benefit, it makes sense. > > this is historically pretty fragile code so bringing the 32-bit and > 64-bit variants more in line sounds like a good reason to me. For > example we had various long-living irq state annotation bugs (the > combination of kprobes and lockdep, etc.) that remained unfixed partly > due to this assymetry. > Agreed completely. I certainly didn't mean to come across sounding negative. -hpa