On Thu, 13 Sep 2012, Dave Martin wrote:
Do you think it's feasible to standardise on some interoperable ABI for kvm and Xen? This sounds pretty optimistic, but I'm not aware of all the technicalities, or what possible third-party hypervisors are out there.
If we could do it, it would be good. But I have my doubts about the feasibility and the benefits. If different hypervisors are significantly imcompatible, then having a common low-level ABI doesn't help all that much.
It is not really possible because each hypervisor offers a different set of hypercalls and has a different calling convention, so there is very little we can do to unify them.
For example many of the current Xen hypercalls are to deal with the grant table and event channels, that are Xen specific concepts completely missing in KVM.