Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932315AbWJFTLl (ORCPT ); Fri, 6 Oct 2006 15:11:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932450AbWJFTLl (ORCPT ); Fri, 6 Oct 2006 15:11:41 -0400 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:44991 "EHLO ebiederm.dsl.xmission.com") by vger.kernel.org with ESMTP id S932315AbWJFTLj (ORCPT ); Fri, 6 Oct 2006 15:11:39 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: "H. Peter Anvin" Cc: vgoyal@in.ibm.com, Andrew Morton , linux kernel mailing list , Reloc Kernel List , ak@suse.de, horms@verge.net.au, lace@jankratochvil.net, magnus.damm@gmail.com, lwang@redhat.com, dzickus@redhat.com, maneesh@in.ibm.com Subject: Re: [PATCH 12/12] i386 boot: Add an ELF header to bzImage References: <20061003170032.GA30036@in.ibm.com> <20061003172511.GL3164@in.ibm.com> <20061003201340.afa7bfce.akpm@osdl.org> <20061004214403.e7d9f23b.akpm@osdl.org> <20061004233137.97451b73.akpm@osdl.org> <20061005235909.75178c09.akpm@osdl.org> <20061006183846.GF19756@in.ibm.com> <4526A66B.4030805@zytor.com> Date: Fri, 06 Oct 2006 13:09:34 -0600 In-Reply-To: <4526A66B.4030805@zytor.com> (H. Peter Anvin's message of "Fri, 06 Oct 2006 11:54:35 -0700") Message-ID: User-Agent: Gnus/5.110004 (No Gnus v0.4) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1316 Lines: 35 "H. Peter Anvin" writes: > Vivek Goyal wrote: >>> >> Hi Eric, >> I have added cld in the regenerated patch below. > > No, the cld needs to be earlier. It turns out this isn't the first use of > string instructions. Can we rely on the int calls not setting df? Otherwise we need to clear df at each use as we do with all of the later uses. > I think I am going to add DF=0 as a documented entry condition; it definitely > seems all current Linux kernels require it. > >> Also one more minor nit. stosb relies on being %es set properly. By the >> time control reaches loader_ok, i could not find %es being set explicitly >> hence I am assuming we are relying on bootloader to set it up for us. Maybe we >> can be little more paranoid and setup the %es before stosb. I >> have done this change too in the attached patch. Pleaese have a look. >> I know little about assembly code. > > %es being set is part of the requirements list, although it *would* be better to > not rely on any segment registers being set at all (only rely on %cs.) Agreed. Eric - 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/