[Qemu-devel] Re: Qemu-KVM Livate Migration 0.12.2 -> 0.12.3/4 broken?

[Avi Kivity <avi@redhat.com>]

On 05/16/2010 05:42 PM, Juan Quintela wrote:
>
>> Any idea why it fails?  And how to fix it?
>>      
> Lack of "proper" subsections.  IDE is something like:
>
> const VMStateDescription vmstate_ide_drive = {
>      .version_id = 4,
> ....
> }
>
> static const VMStateDescription vmstate_bmdma = {
>      .name = "ide bmdma",
>      .version_id = 4,
> ...
> }
>
> const VMStateDescription vmstate_ide_pci = {
>      .name = "ide",
>      .version_id = 4,
> ....
>          VMSTATE_STRUCT_ARRAY(bmdma, PCIIDEState, 2, 0,
>                       vmstate_bmdma, BMDMAState),
>          VMSTATE_IDE_DRIVES(bus[0].ifs, PCIIDEState),
>          VMSTATE_IDE_DRIVES(bus[1].ifs, PCIIDEState),
> ....
> }
>
>
> Notice that everything is at version 4.  It used to be everything at
> version 3.  Now the problem is that when migrating from v3 ->  v4.  We
> put in one place v3, But we only have a version number at the toplevel,
> rest of "subsections" don't sent a version number.  There is no way to
> fix it in the general case.  We can hack something around for ide, but
> that will just be a hack, or we can backport marcelo change and port it
> as a proper subsection (that is my plan).  I expect to have time at the
> end of next time to work on this.
>    

end of next week?

> So, to make the story short: I know what is happening, and I know how to
> fix it, just that fix is not trivial.  I just need time.
>    

Meanwhile, we have a broken 0.12.4.  Is there a quick'n'dirty workaround 
that will be forward compatible with the real fix that we can push out?

We've regressed from failing some migrations to failing all migrations.

-- 
error compiling committee.c: too many arguments to function