Re: [Qemu-devel] [PATCH 00/21] Kemari for KVM 0.2

Paul Brook
2010-11-29T13:19:40Z

> 2010/11/29 Paul Brook <paul@codesourcery.com>:
> >> >> Could you formulate the constraints so developers are aware of them
> >> >> in the future and can protect the codebase. How about expanding the
> >> >> Kemari wiki pages?
> >> >
> >> > If you like the idea above, I'm happy to make the list also on
> >> > the wiki page.
> >>
> >> Here's a different question: what requirements must an emulated device
> >> meet in order to be added to the Kemari supported whitelist? That's
> >> what I want to know so that I don't break existing devices and can add
> >> new devices that work with Kemari :).
> >
> > Why isn't it completely device agnostic? i.e. if a device has to care
> > about Kemari at all (of vice-versa) then IMO you're doing it wrong. The
> > whole point of the internal block/net APIs is that they isolate the host
> > implementation details from the device emulation.
>
> You're right "theoretically". But what I've learned so far,
> there are cases like virtio-net and e1000 woks but virtio-blk
> doesn't. "Theoretically", any emulated device should be able to
> get into the whitelist if the event-tap is properly implemented
> but sometimes it doesn't seem to be that simple.
>
> To answer Stefan's question, there shouldn't be any requirement
> for a device, but must be tested with Kemari. If it doesn't work
> correctly, the problems must be fixed before adding to the list.

What exactly are the problems? Is this a device bus of a Kemari bug?
If it's the former then that implies you're imposing additional requirements
that weren't previously part of the API. If the latter, then it's a bug like
any other.

Paul