Re: [Qemu-devel] [PATCH] [virtio] Add virtio block device sanboot support

[Gerd Hoffmann <kraxel@redhat.com>]

On 01/05/10 21:46, Stefan Hajnoczi wrote:
> This patch adds virtio block device support alongside the existing iSCSI,
> ATA-over-Ethernet, and ramdisk block devices.  The virtio block device provides
> storage in virtualized environments.
>
> Using this patch, a gPXE option ROM can boot a QEMU/KVM virtual machine
> directly from a virtio block device.

Great.

> Here is an example QEMU invocation:
> qemu -drive if=virtio,file=debian.qcow2 -option-rom gpxe/src/bin/1af41001.rom

> Perhaps the first available device should be chosen if virtio_blk: is given
> without PCI bus, device, and function.  I am open to suggestions on how virtio
> block device option ROMs should work.

Clear answer: as PCI ROM.

Try this (requires qemu 0.12):

qemu -drive if=none,id=boot,file=debian.qcow2 \
      -device virtio-blk-pci,drive=boot,romfile=gpxe/src/bin/1af41001.rom

You should end up with a virtio-blk device with a pci rom bar holding 
the option rom.  seabios should load and run the rom.  The disk should 
appear in the boot menu (enabled by '-boot menu=on').

cheers,
   Gerd