From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964836AbWLULUJ (ORCPT ); Thu, 21 Dec 2006 06:20:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964845AbWLULUJ (ORCPT ); Thu, 21 Dec 2006 06:20:09 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:42042 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964836AbWLULUH (ORCPT ); Thu, 21 Dec 2006 06:20:07 -0500 Date: Thu, 21 Dec 2006 12:15:33 +0100 From: Ingo Molnar To: Muli Ben-Yehuda Cc: Linus Torvalds , linux-kernel@vger.kernel.org, Dave Jones , Andrew Morton Subject: Re: [patch] x86_64: fix boot hang caused by CALGARY_IOMMU_ENABLED_BY_DEFAULT Message-ID: <20061221111533.GA31433@elte.hu> References: <20061220102846.GA17139@elte.hu> <20061220113052.GA30145@rhun.ibm.com> <20061220162338.GC11804@elte.hu> <20061220180953.GM30145@rhun.ibm.com> <20061221103702.GA19451@elte.hu> <20061221110914.GY30145@rhun.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061221110914.GY30145@rhun.ibm.com> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -5.9 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-5.9 required=5.9 tests=ALL_TRUSTED,BAYES_00 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Muli Ben-Yehuda wrote: > > but i still /strongly/ disagree with your attitude that mainline is > > 'experimental' and hence there's nothing to see here, move over. > > We can agree to disagree about how "experimental" mainline should be. > [...] there's not much to disagree about. Mainline early bootup _must not break_, and if it breaks, it must be easy for the tester to figure it out. Simple as that. If it ever breaks and the user cannot give us other feedback but: "my laptop hung", we screwed up the process! once the system has booted up into a minimal state, up to the stage where say netconsole works, we've got an exponentially increasing number of measures to find /all the other bugs/. But early bootup is like sacred. It's not experimental at all. Really. Having a system that doesnt even boot and gives no feedback at all is an absolute showstopper and a lost tester to us. if we need draconian measures such as having two versions of early bootup code present in the kernel and a runtime boot switch to trigger between the old-trusted and the new-unknown one [perhaps even automatically, via the help of Grub] then so it be - but we cannot tolerate hung bootups. Ingo