From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Ml3CD-0003am-40 for qemu-devel@nongnu.org; Tue, 08 Sep 2009 12:05:29 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Ml3C8-0003U9-HM for qemu-devel@nongnu.org; Tue, 08 Sep 2009 12:05:28 -0400 Received: from [199.232.76.173] (port=41777 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Ml3C8-0003Tt-6L for qemu-devel@nongnu.org; Tue, 08 Sep 2009 12:05:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:7652) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1Ml3C7-0001Fn-Gn for qemu-devel@nongnu.org; Tue, 08 Sep 2009 12:05:23 -0400 Message-ID: <4AA680BB.5020201@redhat.com> Date: Tue, 08 Sep 2009 19:05:15 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: [PATCH 0/2] port over extboot from kvm References: <1252401463-3249-1-git-send-email-kraxel@redhat.com> <4AA6607C.4050505@siemens.com> <4AA668A2.1080801@redhat.com> <4AA66B10.2050901@codemonkey.ws> In-Reply-To: <4AA66B10.2050901@codemonkey.ws> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Jan Kiszka , Gerd Hoffmann , qemu-devel@nongnu.org On 09/08/2009 05:32 PM, Anthony Liguori wrote: > Gerd Hoffmann wrote: >> On 09/08/09 15:47, Jan Kiszka wrote: >> >>> Before setting this definitely useful feature in stone, I have two >>> questions though: >>> >>> - -drive ...,boot=on is logically in conflict with -boot. Yes, -boot > > x86 boot is strange. The BIOS boots from the "first hard disk" What > extboot allows you do to is redefine to the bios what constitutes the > "first hard disk". It's not just booting - it's the int 0x13 interface. Grub for example continues to use it and can boot from the second hard disk if desired. > > This is the motivation for making it a -drive option. Perhaps this is > something we want to hide from the user but that was the motivation. I agree with this and I think we should extend it to boot=0x80|0x81.... boot=on is an alias to boot=0x80. > > For instance, it would not be possible to define a boot sequence of > "first virtio disk, then second virtio disk, then cdrom" because we > can't present two disks as the first hard disk. > > If extboot supported BCV and our bios did, the above would be possible. > -- error compiling committee.c: too many arguments to function