30 Jan
2019
30 Jan
'19
3 a.m.
Hi,
(Migration compat is left as an exercise for the reader :-))
It's not just migration compatibility, it's also guest ABI: "the guest can tell the difference".
Is that actually the case on x86? I don't think so. Note: arm is different, because the flash is listed in the device tree which is guest visible.
So, old machine types continue to get two flash devices, and new machine types get one. In other words, we're stuck maintaining (a) even if we decide to switch to (b).
I think that'll be true nevertheless for live migration compatibility. cheers, Gerd