Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755300AbWKMSAi (ORCPT ); Mon, 13 Nov 2006 13:00:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755301AbWKMSAi (ORCPT ); Mon, 13 Nov 2006 13:00:38 -0500 Received: from e3.ny.us.ibm.com ([32.97.182.143]:50570 "EHLO e3.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1755300AbWKMSAh (ORCPT ); Mon, 13 Nov 2006 13:00:37 -0500 Date: Mon, 13 Nov 2006 12:59:47 -0500 From: Vivek Goyal To: Andi Kleen Cc: linux kernel mailing list , Reloc Kernel List , ebiederm@xmission.com, akpm@osdl.org, hpa@zytor.com, magnus.damm@gmail.com, lwang@redhat.com, dzickus@redhat.com, pavel@suse.cz, "Rafael J. Wysocki" Subject: Re: [RFC] [PATCH 10/16] x86_64: 64bit PIC ACPI wakeup Message-ID: <20061113175947.GA13832@in.ibm.com> Reply-To: vgoyal@in.ibm.com References: <20061113162135.GA17429@in.ibm.com> <20061113164314.GK17429@in.ibm.com> <200611131822.44034.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200611131822.44034.ak@suse.de> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1170 Lines: 33 On Mon, Nov 13, 2006 at 06:22:43PM +0100, Andi Kleen wrote: [..] > > > +verify_cpu: > > + pushl $0 # Kill any dangerous flags > > + popfl > > + > > + /* minimum CPUID flags for x86-64 */ > > + /* see http://www.x86-64.org/lists/discuss/msg02971.html */ > > +#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\ > > + (1<<13)|(1<<15)|(1<<24)|(1<<25)|(1<<26)) > > +#define REQUIRED_MASK2 (1<<29) > > It would be much better if this least this CPUID code was in a common shared > file with head.S Hi Andi, This code (verify_cpu) is called while we are still in real mode. So it has to be present in low 1MB. Now in trampoline has been designed to switch to 64bit mode and then jump to the kernel hence kernel can be loaded anywhere even beyond (4G). So if we move this code into say arch/x86_64/kernel/head.S then we can't even call it. So I think we got to leave it in trampoline only. Thanks Vivek - 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/