From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752603AbYFSElS (ORCPT ); Thu, 19 Jun 2008 00:41:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750950AbYFSElH (ORCPT ); Thu, 19 Jun 2008 00:41:07 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:36542 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750897AbYFSElG (ORCPT ); Thu, 19 Jun 2008 00:41:06 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: "Yinghai Lu" Cc: "Len Brown" , "Ingo Molnar" , "Thomas Gleixner" , "H. Peter Anvin" , "Andrew Morton" , "linux-kernel@vger.kernel.org" References: <200805041823.57198.yhlu.kernel@gmail.com> <200805191252.36814.yhlu.kernel@gmail.com> <200805251600.26325.yhlu.kernel@gmail.com> <200806011317.38622.yhlu.kernel@gmail.com> <86802c440806181532g348864e1u3d067f8366046a7f@mail.gmail.com> <86802c440806181749g2faf1892iea693717ea919631@mail.gmail.com> Date: Wed, 18 Jun 2008 21:32:01 -0700 In-Reply-To: <86802c440806181749g2faf1892iea693717ea919631@mail.gmail.com> (Yinghai Lu's message of "Wed, 18 Jun 2008 17:49:16 -0700") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SA-Exim-Connect-IP: 24.130.11.59 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-DCC: XMission; sa03 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;"Yinghai Lu" X-Spam-Relay-Country: X-Spam-Report: * -1.8 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% * [score: 0.0008] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa03 1397; Body=1 Fuz1=1 Fuz2=1] * 0.0 XM_SPF_Neutral SPF-Neutral Subject: Re: [PATCH] x86: update mptable v7 X-SA-Exim-Version: 4.2 (built Thu, 03 Mar 2005 10:44:12 +0100) X-SA-Exim-Scanned: Yes (on mgr1.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "Yinghai Lu" writes: > On Wed, Jun 18, 2008 at 5:33 PM, Len Brown wrote: >> >> >> On Wed, 18 Jun 2008, Yinghai Lu wrote: >> >>> On Wed, Jun 18, 2008 at 3:18 PM, Len Brown wrote: >>> > >>> > >>> > On Sun, 1 Jun 2008, Yinghai Lu wrote: >>> > >>> >> >>> >> make mptable to be consistent to acpi routing, so we could >>> >> 1. kexec kernel with acpi=off >>> >> 2. workaround BIOS that acpi routing is working, but mptable is not right. >>> >> so can use kernel/kexec to start other os that doesn't have good acpi > support >>> > >>> > Is this an effort to boot an ACPI-mode kernel, >>> > and then kexec a non-ACPI kernel? >>> >>> Yes, >> >> Why is this feature needed? >> There are a number of ways that the resulting kernel may fail, >> all platform specific. > > other os still doesn't have update acpi irq routing support. but has > broken mptable. Which is at least in part a reason to go back to the BIOS manufacturer and get them to fix their table. I can see a warning coming from the kernel if these two tables are inconsistent though. >>> > Doing so could confuse the heck out of the platform firmware, >>> > which will think that an ACPI-mode kernel is still running. >>> > >>> > Note that it is a historic artifact, now considered a bug, >>> > that ACPI uses the MPS code. We should be divorcing these >>> > two bodies of code rather than mixing them further. >>> >>> how about adding config option to not compile mptable related info? >> >> That's the idea. >> CONFIG_MPS=n CONFIG_ACPI=y should build and run on >> every PC built in this century. >> >> This was prototyped a long while back, but the >> tree has churned so much since then the old >> prototype is worthless. > > will look at it tonight. > > when EFI is popular, there is no reason to compile mps related stuff > in kernel again. esp for 64 bit. ? EFI has nothing to do with this. ACPI is popular today and EFI preserves EFI. > BTW, it is funny that Suse still has fallsafe boot entry with acpi=off. Silly question. Given that even writing to this table is platform specific. Any chance we can do this any a userspace utility writing through /dev/mem for the systems that need it? We can even bundle the utility in the kexec-tools package to make it easier to distribute. Eric