From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NAN9M-000513-QA for qemu-devel@nongnu.org; Tue, 17 Nov 2009 07:27:12 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NAN9H-0004v5-HC for qemu-devel@nongnu.org; Tue, 17 Nov 2009 07:27:11 -0500 Received: from [199.232.76.173] (port=50597 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NAN9H-0004uo-2J for qemu-devel@nongnu.org; Tue, 17 Nov 2009 07:27:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:13462) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NAN9G-0001zf-Mb for qemu-devel@nongnu.org; Tue, 17 Nov 2009 07:27:06 -0500 Message-ID: <4B02968C.6060606@redhat.com> Date: Tue, 17 Nov 2009 13:26:52 +0100 From: Gerd Hoffmann MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 0/2] extboot reloaded. References: <1258394678-8634-1-git-send-email-kraxel@redhat.com> <4B01B419.50905@redhat.com> <4B01C0B9.8060507@codemonkey.ws> <200911171136.33909.paul@codesourcery.com> In-Reply-To: <200911171136.33909.paul@codesourcery.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paul Brook Cc: Kevin O'Connor , qemu-devel@nongnu.org On 11/17/09 12:36, Paul Brook wrote: >>>> It would require a mechanism to do enumeration and identification >>>> though. >>> >>> Huh? Do you want export *all* block devices via extboot? Will IDE >>> drives show up twice then? >> >> No, because SeaBIOS already has an ATA driver so we wouldn't want to >> expose IDE on the extboot bus. > > "SeaBIOS already has an ATA driver" doesn't seem a convincing argument for > making IDE special, because I expect the BIOS will grow support for other > block devices. One of the reasons why I'd enable it only on explicit user request, so it can be used (temporarily) for cases where the bios has no native support. > Either expose ever block device qemu knows about, or have extboot as a regular > block device with no special handling. I strongly prefer the latter option. Me too. > In fact I'd much prefer to see extboot rewritten to just virtio-block. Hmm, I'd prefer something which is *not* used by the guest OS, so it is a pure bootloader thing. When using it to boot from scsi you don't want to have the disk show up twice (as virtio and scsi) in the guest. Some non-pci virtio proxy could do the trick though, i.e. have virtio-blk-pci and virtio-blk-boot. Would probably also simplify things on the seabios side as native virtio support code could be reused then. cheers, Gerd