From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755504AbYAOM6m (ORCPT ); Tue, 15 Jan 2008 07:58:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750851AbYAOM6e (ORCPT ); Tue, 15 Jan 2008 07:58:34 -0500 Received: from terminus.zytor.com ([198.137.202.10]:53386 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750743AbYAOM6e (ORCPT ); Tue, 15 Jan 2008 07:58:34 -0500 Message-ID: <478CAC70.80309@zytor.com> Date: Tue, 15 Jan 2008 07:52:00 -0500 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: "Huang, Ying" CC: Ingo Molnar , venkatesh.pallipadi@intel.com, akpm@linux-foundation.org, Thomas Gleixner , Ingo Molnar , Andi Kleen , linux-kernel@vger.kernel.org Subject: Re: [PATCH -mm 0/3] i386 boot: replace boot_ioremap with enhanced bt_ioremap References: <1200375902.3505.29.camel@caritas-dev.intel.com> <20080115084417.GA16449@elte.hu> <1200390535.3505.62.camel@caritas-dev.intel.com> In-Reply-To: <1200390535.3505.62.camel@caritas-dev.intel.com> 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 Huang, Ying wrote: > > After checking the early_ioremap() implementation in > arch/x86/kernel/setup_32.c, I found that it is a duplication of > bt_ioremap() implementation in arch/x86/mm/ioremap_32.c. Both > implementations use set_fixmap(), so they can be used only after > paging_init(). > > The early_ioremap implementation provided in this patchset works as > follow: > > - Enhances bt_ioremap, make it usable before paging_init() via a > dedicated PTE page. > - Rename bt_ioremap to early_ioremap > > So I think maybe we should replace the early_ioremap() implementation in > PAT series with that of this series. > I did a quick scan over the patchset (not quite awake yet, so I may very well have missed something), but it looks like EFI (again!) is the only user of ioremapping before paging_init(). This makes me wonder if that code can't be restructured so that isn't necessary. -hpa