From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760218AbYFYOqQ (ORCPT ); Wed, 25 Jun 2008 10:46:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760055AbYFYOpW (ORCPT ); Wed, 25 Jun 2008 10:45:22 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:44484 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751250AbYFYOpU (ORCPT ); Wed, 25 Jun 2008 10:45:20 -0400 Date: Wed, 25 Jun 2008 16:45:05 +0200 From: Ingo Molnar To: Yinghai Lu Cc: Thomas Gleixner , "H. Peter Anvin" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] x86: introduce init_memory_mapping for 32bit Message-ID: <20080625144504.GA18796@elte.hu> References: <200806231951.10898.yhlu.kernel@gmail.com> <200806240410.47856.yhlu.kernel@gmail.com> <20080624113049.GA7731@elte.hu> <86802c440806241222h574c2a1cidf4191f7f6f3f372@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <86802c440806241222h574c2a1cidf4191f7f6f3f372@mail.gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Yinghai Lu wrote: > On Tue, Jun 24, 2008 at 4:30 AM, Ingo Molnar wrote: > > > > * Yinghai Lu wrote: > > > >> so could use mem below max_low_pfn as early. could move several > >> function more early instead of waiting after paging_init including > >> moving relocate_initrd early, and kva related early done in > >> initmem_init > > > > applied to tip/x86/setup-memory - thanks Yinghai. > > > > a sidenote: > > > >> 6 files changed, 128 insertions(+), 74 deletions(-) > > > > this patch is too large - if it causes any problems it will not be very > > easy to figure out which exact change caused the problems. > > > > Lets hope it goes all fine - but in the future lets try doing > > more+smaller patches, especially if they change some known-dangerous > > area of the kernel. > > > > For example here a better splitup would have been to do 5 or more > > patches: > > > > 1) first introduce init_memory_mapping() [but dont use it anywhere] > > 2) add the init_memory_mapping() call to setup_arch() > > 3) move remap_numa_kva() > > 4) move relocate_initrd() > > 5) remove the now unnecessary setup from paging_init() > > > > ... or something like that. The point is to manage risk: if there's > > multiple problem areas that a change is touching, try to isolate them > > from each other and introduce the change gradually. > > > > The end result is still exactly the same, but much more > > reviewable/debuggable/bisectable. > > split into 3 patches, please use them to replace the old one if you > like. i've applied them to tip/x86/setup-memory, replacing the larger patch - thanks Yinghai. Ingo