[libvirt] [Qemu-devel] [PATCH] [RFC] Add machine type pc-1.0-qemu-kvm for live migrate compatibility with qemu-kvm

Alex Bligh alex at alex.org.uk
Tue Jul 29 13:56:28 UTC 2014

On 29 Jul 2014, at 14:42, Paolo Bonzini <pbonzini at redhat.com> wrote:

> Il 29/07/2014 15:39, Alex Bligh ha scritto:
>>>> I'm not sure either.  You could simply package the 12.04 ipxe ROMs into
>>>> 14.04, and add a note about getting the sources for GPL friendliness.
>> This would be my preference (or in Ubuntu's case, add it to the ipxe-qemu
>> package) but I think it should only be used when the legacy machine type
>> is used or it will break inbound migrations from other 14.04 machines
>> started with 128k ROMs (AIUI).
> "-M pc" and its alias "-M pc-i440fx-2.0" doesn't use pxe-virtio.rom at
> all (at least upstream).

Really? How does it pxeboot on virtio then (it definitely does pxeboot
on virtio)?

>  Does Ubuntu 14.04 have efi-virtio.rom?

Yes. After 2 layers of symlinks you get to.

ubuntu at trustytest:~$ ls -la /usr/lib/ipxe/qemu/efi-virtio.rom
-rw-r--r-- 1 root root 220672 Jan  6  2014 /usr/lib/ipxe/qemu/efi-virtio.rom

> It would break "-M pc-1.0" started on older 14.04, but I think that's
> acceptable.

I was more worried about any previous versions of Ubuntu (newer than
12.04) which might also be using the larger rom size. But then I
haven't investigated at what stage the rom size grew.

Alex Bligh

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