From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753832AbXD2Rv7 (ORCPT ); Sun, 29 Apr 2007 13:51:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753872AbXD2Rv7 (ORCPT ); Sun, 29 Apr 2007 13:51:59 -0400 Received: from terminus.zytor.com ([192.83.249.54]:34990 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753832AbXD2Rv6 (ORCPT ); Sun, 29 Apr 2007 13:51:58 -0400 Message-ID: <4634DB24.7020408@zytor.com> Date: Sun, 29 Apr 2007 10:51:32 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.0 (X11/20070419) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: "Eric W. Biederman" , Jeff Garzik , Andi Kleen , patches@x86-64.org, Vivek Goyal , linux-kernel@vger.kernel.org Subject: Re: [patches] [PATCH] [21/22] x86_64: Extend bzImage protocol for relocatable bzImage References: <20070428758.455116000@suse.de> <20070428175909.1D09D151CA@wotan.suse.de> <46338D72.70402@garzik.org> <4634483E.9030307@goop.org> In-Reply-To: <4634483E.9030307@goop.org> X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge wrote: > Eric W. Biederman wrote: >> All it does is set a flag that tells a bootloader. >> "Hey. I can run when loaded a non-default address, and this is what >> you have to align me to." >> >> All relocation processing happens in the kernel itself. >> > > Is it possible to decompress and extract the kernel image from the > bzImage without executing it? Ie, is there enough information to find > the compressed data part of the bzImage by inspection? > > At some point we'll need to change the Xen domain builder to handle > bzImage files, and it would be best if we didn't need to run them. > Probabilistically, you might be able to (search for a gzip header), but it is *definitely* not guaranteed by protocol. -hpa