From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934161AbXGKWwn (ORCPT ); Wed, 11 Jul 2007 18:52:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757855AbXGKWwf (ORCPT ); Wed, 11 Jul 2007 18:52:35 -0400 Received: from 216-99-217-87.dsl.aracnet.com ([216.99.217.87]:34910 "EHLO sous-sol.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757369AbXGKWwf (ORCPT ); Wed, 11 Jul 2007 18:52:35 -0400 Date: Wed, 11 Jul 2007 15:51:39 -0700 From: Chris Wright To: Linus Torvalds Cc: Thomas Gleixner , Ingo Molnar , Andi Kleen , Andrew Morton , linux-kernel@vger.kernel.org, Arjan van de Ven , Chris Wright Subject: Re: x86 status was Re: -mm merge plans for 2.6.23 Message-ID: <20070711225139.GB4306@sequoia.sous-sol.org> References: <20070710013152.ef2cd200.akpm@linux-foundation.org> <20070711174252.GA16793@elte.hu> <1184191488.12353.160.camel@chaos> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.14 (2007-02-12) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Linus Torvalds (torvalds@linux-foundation.org) wrote: > For example, we can make sure that the code in question that actually > touches the hardware stays exactly the same, and then just move the > interfaces around - and basically guarantee that _zero_ hardware-specific > issues pop up when you switch over, for example. That's not quite right. Leaving the code unchanged caused breakage already. The PIT is damn stupid and can be sensitive to how quickly it's programmed. So code that enable/disable didn't change, but frequency with which it is called did and broke some random boxes. > The other approach (which would be nice _too_) is to actually try to > convert one clock source at a time. Why is that not an option? It was that way for x86_64, that's the first thing I fixed (since it was done by fully disabling all other timers but the one coverted ;-)