From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1Vntl3-0004Cm-Fa for mharc-grub-devel@gnu.org; Tue, 03 Dec 2013 12:27:37 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60568) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vntl0-0004Bj-KW for grub-devel@gnu.org; Tue, 03 Dec 2013 12:27:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Vntky-0003gB-Mz for grub-devel@gnu.org; Tue, 03 Dec 2013 12:27:34 -0500 Received: from v6.chiark.greenend.org.uk ([2001:ba8:1e3::]:39215 helo=chiark.greenend.org.uk) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vntky-0003fy-Hq for grub-devel@gnu.org; Tue, 03 Dec 2013 12:27:32 -0500 Received: from [172.20.153.9] (helo=riva.pelham.vpn.ucam.org) by chiark.greenend.org.uk (Debian Exim 4.72 #1) with esmtps (return-path cjwatson@ubuntu.com) id 1Vntkx-0000Mc-AZ; Tue, 03 Dec 2013 17:27:31 +0000 Received: from ns1.pelham.vpn.ucam.org ([172.20.153.2] helo=riva.ucam.org) by riva.pelham.vpn.ucam.org with esmtps (TLS1.2:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.80) (envelope-from ) id 1Vntkv-00010t-LW; Tue, 03 Dec 2013 17:27:29 +0000 Date: Tue, 3 Dec 2013 17:27:28 +0000 From: Colin Watson To: The development of GNU GRUB Subject: Re: [Xen-devel] pvgrub2 is merged Message-ID: <20131203172728.GA3709@riva.ucam.org> References: <527EA084.6000706@gmail.com> <20131129132422.GC16321@riva.ucam.org> <20131129214427.02439ae0@opensuse.site> <1385977687.7108.11.camel@kazak.uk.xensource.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1385977687.7108.11.camel@kazak.uk.xensource.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2001:ba8:1e3:: Cc: "xen-devel@lists.xen.org" X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list Reply-To: The development of GNU GRUB List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Dec 2013 17:27:35 -0000 On Mon, Dec 02, 2013 at 09:48:07AM +0000, Ian Campbell wrote: > On Fri, 2013-11-29 at 21:44 +0400, Andrey Borzenkov wrote: > > В Fri, 29 Nov 2013 13:24:22 +0000 > > Colin Watson пишет: > > > Could anyone offer packaging advice for which ports should be built > > > here? Is it reasonable to assume that a 32-bit userspace only needs the > > > 32-bit Xen port and a 64-bit userspace only needs the 64-bit Xen port, > > > or is it possible that there could be cross-architecture combinations > > > here? Does the architecture of the GRUB port have to match the > > > architecture of the Xen hypervisor? > > > > I guess this question is better asked on xen-devel. Assuming we have 64 > > bit dom0 and try to boot 32 bit domU. Is it possible to start with > > loading 64 bit grub that loads 32 bit kernel and jumps to it? If yes > > (and in other direction too) situation becomes relatively simple. > > AIUI it is not in general possible for a 32-bit PV guest to convert > itself to 64-bit or vice versa, which is essentially what would have to > happen to boot the other type of kernel. So once you have selected the > grub binary to use it cannot boot the other type of kernel. (Yes, this > is an annoying technical restriction...) > > It is however possible to run 32-bit and 64-bit guests on a 32-bit dom0 > with a 64-bit underlying hypervisor. It is also possible to run both > types of guest on a 64-bit kernel and 64-bit underlying hypervisor. > > So, for packaging purposes it would be best to provide both 32- and > 64-bit grub binaries for both 32- and 64-bit userspace. Thanks for the feedback. I'm inclined, then, to just ship both in the same grub-xen binary package (actually the pattern is grub-xen{,-bin,-dbg} but never mind that for now). It's a bit different from the usual case since you might well want to actively use both on the same system, and I don't think we would get much out of the two ports being in separate packages. -- Colin Watson [cjwatson@ubuntu.com]