On Fri, Oct 09, 2009 at 09:55:13PM +0200, Juan Quintela wrote: > Jamie Lokier <jamie@xxxxxxxxxxxxx> wrote: > > Glauber Costa wrote: > >> On Thu, Oct 08, 2009 at 06:22:48PM +0200, Gleb Natapov wrote: > >> > On Thu, Oct 08, 2009 at 06:17:57PM +0200, Avi Kivity wrote: > >> > > On 10/08/2009 06:07 PM, Jamie Lokier wrote: > >> > > >Haven't we already confirmed that it *isn't* just an ioapic accelerator > >> > > >because you can't migrate between in-kernel iopic and qemu's ioapic? > >> > > > >> > > We haven't confirmed it. Both implement the same spec, and if you > >> > > can't migrate between them, one of them has a bug (for example, qemu > >> > > ioapic doesn't implement polarity - but it's still just a bug). > >> > > > >> > Are you saying that HW spec (that only describes software visible behavior) > >> > completely defines implementation? No other internal state is needed > >> > that may be done differently by different implementations? > >> Most specifications leaves a lot as implementation specific. > >> > >> It's not hard to imagine a case in which both devices will follow > >> the spec correctly, (no bugs involved), and yet differ in the > >> implementation. > > > > Avi's not saying the implementations won't differ. I believe he's > > saying that implementation-specific states don't need to be saved if > > they have no effect on guest visible behaviour. > > Just to re-state. I would also prefer to have a single device. Reasons > (majority already told in the thread): > - We can switch between devices more easily > - They are emulating the same device. > - At the moment that you have two different devices, one of them will > rot :( > - Adding state to the save/load format that is used only from one device > is not a problem. > > I notice that discussion is going nowhere, basically we are in the > state: > - people that want one device > * they emulate the same hardware > * lots of code is shared > * they should be interchageable > * if they are not interchageable, it is a bug > * once that they are split, it is basically imposible to join then > again. > - people that want 2 devices: > * The devices can more easily diverge if they are two devices > * They are not interchageable now > * It allows you more freedom in changing any of them if they are > separate. > > As you can see, none of the proposals is a clear winner. And what is > worse, we have the two maintainers (avi and anthony), the two with more > experience having to deal with this kind of situation disagreeing. > > How to fix the impass? a deathmatch? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
