On 07/08/2011 11:59 AM, Gerd Hoffmann wrote:
For scsi-cd and other empty-but-generally-migratable devices we should
probably add an empty vmstate, so that any further addition can be done
as subsections.
That will break migration to older versions which don't know about the
new sections, even if they are empty ...
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.
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. If desired, in
the future we can revert this behavior for pc-0.14 and earlier machines.
Paolo
