Re: [ANNOUNCE] kvm-14 release

Rusty Russell
2007-02-20T01:06:07Z

On Mon, 2007-02-19 at 10:37 -0500, James Morris wrote:
> On Mon, 19 Feb 2007, Avi Kivity wrote:
>
> > Daniel P. Berrange wrote:
> > >> Note that if you use the modules from Linux 2.6.20, you need to use
> > >> kvm-12. You can use kvm-14 with Linux 2.6.20, provided you use the
> > >> external module included in kvm-14.
> > >>
> > >
> > > Is there back-compatability in the reverse direction ? ie, will the
> > > new kmod from kvm-14 work with the older kvm-12 userspace ?
> > >
> >
> > No.
>
> It's traditional for the mainline kernel to maintain backward
> compatibility with existing userspace ABIs (e.g. syscalls).

Stable ABIs are hard, and this is CONFIG_EXPERIMENTAL after all. I
don't think KVM needs ABI stability until CONFIG_EXPERIMENTAL is removed
(of course, sooner is always nice if it doesn't create problems).

Rusty.