Tuesday, February 06, 2007

KVM, Xen, and the Linux kernel

I stumbled upon an article from DevX where Ian Pratt is quoted on a number of topics including KVM and upstream merge. I thought what he said about KVM was a little odd, but what disturbed me was that I think the interviewer misinterpreted what Ian said re: upstream merge. Ian said:

Putting Xen into Linux doesn't make sense: hypervisors are different beasts from operating systems, so they share little code.

He's referring to putting the actual hypervisor into the kernel. Unfortunately, the interviewer took this to mean:

Pratt also explained that Xen is no longer actively seeking inclusion in the mainline Linux kernel either.

Which is totally missing the point. We've never wanted the hypervisor to be included in mainline Linux. It's not a part of Linux so I don't even see how we would do it without major rewrites. What we've been trying to get into the kernel is the Linux changes for guest that run on top of the hypervisor.

We are still very interested in getting the Linux changes upstream. In fact, this is a major priority.