[PATCH 00/19] KVM: PPC: Book3S HV: add XIVE native exploitation mode

[Cédric Le Goater]

>>> As for nesting, I suggest for the foreseeable future we stick to XICS
>>> emulation in nested guests.
>>
>> ok. so no kernel_irqchip at all. hmm. 

I was confused with what Paul calls 'XICS emulation'. It's not the QEMU
XICS emulated device but the XICS-over-XIVE KVM device, the KVM XICS 
device KVM uses when under a P9 processor. 

> That would certainly be step 0, making sure the capability advertises
> this correctly.  I think we do want to make XICs-on-XIVE emulation
> work in a KVM L1 (so we'd need to have it make XIVE hcalls to the L0
> instead of OPAL calls).

With the latest patch of Paul, the KVM XICS device is available for L2
and it works quite well. 

I also want to test it when L1 runs in KVM XIVE native mode, with the 
current patchset, to see how it behaves.

> XIVE-on-XIVE for L1 would be nice too, which would mean implementing
> the XIVE hcalls from the L2 in terms of XIVE hcalls to the L0.  I
> think it's ok to delay this indefinitely as long as the caps advertise
> correctly so that qemu will use userspace emulation until its ready.

ok. I need to fix this in the current patchset.

Thanks,

C.