Re: [Qemu-devel] [PATCH] KVM: Add wrapper script around QEMU to test kernels

[Pekka Enberg]

On Mon, 7 Nov 2011, Frank Ch. Eigler wrote:
> > The ABI design allows for that kind of flexible extensibility, and
> > it's one of its major advantages.
> >
> > What we *cannot* protect against is you relying on obscure details of
> > the ABI [...]
>
> Is there some documentation that clearly spells out which parts of the
> perf syscall userspace ABI are "obscure" and thus presumably
> changeable?

That's actually something the KVM and virtio folks have done a great job 
with IMHO. Both ABIs are documented pretty extensively and the specs are 
kept up to date.

I guess for perf ABI, "perf test" is the closest thing to a specification 
so if your application is using something that's not covered by it, you 
might be in trouble.

                        Pekka