Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762065AbZLJWzV (ORCPT ); Thu, 10 Dec 2009 17:55:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762048AbZLJWzV (ORCPT ); Thu, 10 Dec 2009 17:55:21 -0500 Received: from terminus.zytor.com ([198.137.202.10]:45345 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762005AbZLJWzU (ORCPT ); Thu, 10 Dec 2009 17:55:20 -0500 Message-ID: <4B217C0E.9040801@zytor.com> Date: Thu, 10 Dec 2009 14:54:06 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.4pre) Gecko/20090922 Fedora/3.0-3.9.b4.fc12 Thunderbird/3.0b4 MIME-Version: 1.0 To: Yinghai Lu CC: Jens Axboe , Ingo Molnar , Thomas Gleixner , "linux-kernel@vger.kernel.org" , Randy Dunlap Subject: Re: Bisected regression (Was Re: current -git fails to boot on nehalem-ex) References: <20091210091040.GG8742@kernel.dk> <20091210103945.GI8742@kernel.dk> <20091210160640.GB27794@elte.hu> <67EA4830-231F-45C9-A1A6-CE1C6CD9493D@kernel.org> <20091210180727.GK8742@kernel.dk> <4B213F1F.2020305@kernel.org> <4B2140F8.3020201@kernel.org> <20091210184506.GP8742@kernel.dk> <20091210190742.GS8742@kernel.dk> <4B2149B4.9060900@kernel.org> <20091210192659.GV8742@kernel.dk> <4B21630A.6000308@kernel.org> <4B21789F.4030707@zytor.com> <4B2179FC.6090305@kernel.org> In-Reply-To: <4B2179FC.6090305@kernel.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1037 Lines: 29 On 12/10/2009 02:45 PM, Yinghai Lu wrote: > H. Peter Anvin wrote: >> On 12/10/2009 01:07 PM, Yinghai Lu wrote: >>> it turns out BIOS is using first 64k for mptable without reserve it. >>> >>> so try to find good range for it instead of hard code it. >>> in case some bios try to use that range for sth. >>> >> >> Is this an EFI BIOS? Otherwise, the first 64K would be clobbered anyway >> by the boot loader, so it is invalid anyway... If it is EFI, it is >> theoretically possible. > > Jens said acpi=off works with 2.6.32. > > can you specify the exact byte position that boot loader could touched? > A legacy-BIOS boot loader will typically clobber all memory from 0x600 (in theory 0x501) up to the FBM point; a pointer to the FBM mark is given by (*(uint16_t *)0x413) << 10. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/