On 07/08/2011 01:47 PM, Gerd Hoffmann wrote:
scsi-cd is new in 0.15, older versions have scsi-disk only. That's why
we should take the occasion to add the empty vmstate at least to it.
Ok, good opportunity in that specific case.
For other devices, it's better to make the breakage in a single version.
It also allows to make 0.15 the "flag day" where each device shall have
a VMState or the entire VM will not be migratable.
Not that easy given that we didn't fully migrate to vmstate yet,
otherwise we could simply fail migration in case we find any device with
qdev->vmsd == NULL.
You can always add
#define VMSD_NONE ((const VMStateDescription *) 1)
If desired, in the
future we can revert this behavior for pc-0.14 and earlier machines.
And I'm still looking for a sane way to handle *this*.
One possibility is to add device name remapping to machine types, like
"ide is actually ide-0.14 when using pc-0.14" and put a different
VMState in ide-0.14.
Paolo
