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

On 29 Jul 2014, at 14:42, Paolo Bonzini <pbonzini(a)redhat.com&gt; 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@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.