From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758556AbZB0TVR (ORCPT ); Fri, 27 Feb 2009 14:21:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755739AbZB0TVA (ORCPT ); Fri, 27 Feb 2009 14:21:00 -0500 Received: from terminus.zytor.com ([198.137.202.10]:52192 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755686AbZB0TU7 (ORCPT ); Fri, 27 Feb 2009 14:20:59 -0500 Message-ID: <49A83C52.5050801@zytor.com> Date: Fri, 27 Feb 2009 11:17:38 -0800 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Yinghai Lu , Ingo Molnar , the arch/x86 maintainers , Linux Kernel Mailing List Subject: Re: [PATCH RFC] x86: add brk allocation for very, very early allocations References: <49A829CE.9020509@goop.org> In-Reply-To: <49A829CE.9020509@goop.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge wrote: > > unsigned int boot_cpu_id __read_mostly; > +__initdata unsigned long _brk_start, _brk_end; > Better yet, initialize _brk_start and _brk_end statically: extern const char _end[]; __initdata unsigned long _brk_start = (unsigned long)&_end; __initdata unsigned long _brk_end = (unsigned long)&_end; That way it's available from the first instruction, and we can fully remove the x86-32 init_pg_tables_end and replace it with _brk_end (thus putting the initial page tables in the brk.) -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.