[Qemu-devel] boot from scsi/virtio?

[Qemu-devel] boot from scsi/virtio?

[Gerd Hoffmann]

   Hi folks,

Is it possible to boot from non-ide disks?  kvm has extboot and the 
-drive ...,boot=on syntax to use it.  That isn't in upstream qemu 
though.  Is there another way to boot from non-ide disks?  Or is extboot 
just not yet merged?  Or are there other plans?

cheers,
   Gerd

Re: [Qemu-devel] boot from scsi/virtio?

[Laurent Vivier]

Le vendredi 15 mai 2009 à 10:26 +0200, Gerd Hoffmann a écrit :
> Hi folks,
> 
> Is it possible to boot from non-ide disks?  kvm has extboot and the 
> -drive ...,boot=on syntax to use it.  That isn't in upstream qemu 
> though.  Is there another way to boot from non-ide disks?  Or is extboot 
> just not yet merged?  Or are there other plans?

I did last year a series of patches to enable virtio boot using gPXE
add-on ROM:

http://markmail.org/message/qxqvcrzqitpzrsnb

Regards,
Laurent
-- 
------------------ Laurent.Vivier@bull.net  ------------------
"Tout ce qui est impossible reste à accomplir"    Jules Verne
"Things are only impossible until they're not" Jean-Luc Picard

Re: [Qemu-devel] boot from scsi/virtio?

[Gerd Hoffmann]

On 05/15/09 10:46, Laurent Vivier wrote:
> Le vendredi 15 mai 2009 à 10:26 +0200, Gerd Hoffmann a écrit :
>> Hi folks,
>>
>> Is it possible to boot from non-ide disks?  kvm has extboot and the
>> -drive ...,boot=on syntax to use it.  That isn't in upstream qemu
>> though.  Is there another way to boot from non-ide disks?  Or is extboot
>> just not yet merged?  Or are there other plans?
>
> I did last year a series of patches to enable virtio boot using gPXE
> add-on ROM:
>
> http://markmail.org/message/qxqvcrzqitpzrsnb

Didn't got merged it seems.  git tree hasn't a block subdir.  Also 
rom-o-magic offers virtio-net only.  And it doesn't solve the scsi 
booting issue, right?

cheers,
   Gerd

Re: [Qemu-devel] boot from scsi/virtio?

[Laurent Vivier]

[-- Attachment #1: Type: text/plain, Size: 1462 bytes --]

Le vendredi 15 mai 2009 à 10:54 +0200, Gerd Hoffmann a écrit :
> On 05/15/09 10:46, Laurent Vivier wrote:
> > Le vendredi 15 mai 2009 à 10:26 +0200, Gerd Hoffmann a écrit :
> >> Hi folks,
> >>
> >> Is it possible to boot from non-ide disks?  kvm has extboot and the
> >> -drive ...,boot=on syntax to use it.  That isn't in upstream qemu
> >> though.  Is there another way to boot from non-ide disks?  Or is extboot
> >> just not yet merged?  Or are there other plans?
> >
> > I did last year a series of patches to enable virtio boot using gPXE
> > add-on ROM:
> >
> > http://markmail.org/message/qxqvcrzqitpzrsnb
> 
> Didn't got merged it seems.  git tree hasn't a block subdir.  Also 
> rom-o-magic offers virtio-net only.  And it doesn't solve the scsi 
> booting issue, right?

Yes, I didn't finish this work and didn't push it to the git tree.
It introduces block device support into gPXE and a virtio-block driver
using it. To support SCSI we have to write the SCSI driver too...

Attached, an old ROM I found on my disk (not tested recently) ...
(use it with "-driver file=...,if=virtio -option-rom virtio-blk.brom")

You can use it to boot from a CDROM too (but the kernel doesn't have
support for that)

Regards,
Laurent
-- 
------------------ Laurent.Vivier@bull.net  ------------------
"Tout ce qui est impossible reste à accomplir"    Jules Verne
"Things are only impossible until they're not" Jean-Luc Picard

[-- Attachment #2: virtio-blk.brom --]
[-- Type: application/octet-stream, Size: 51200 bytes --]

[Qemu-devel] Re: boot from scsi/virtio?

[Sebastian Herbszt]

Gerd Hoffmann wrote:
>   Hi folks,
> 
> Is it possible to boot from non-ide disks?  kvm has extboot and the 
> -drive ...,boot=on syntax to use it.  That isn't in upstream qemu 
> though.  Is there another way to boot from non-ide disks?  Or is extboot 
> just not yet merged?  Or are there other plans?
> 
> cheers,
>   Gerd

For LSI53C895A scsi you can try to get the LSI rom (8xx_64.rom) working.
I tried it some time ago, but didn't get too far because the scsi controller
emulation isn't flawless yet. I posted one of the needed patches [1].

[1] http://lists.gnu.org/archive/html/qemu-devel/2008-12/msg01569.html

- Sebastian