ESX on KVM requirements

[Ben Sanders <ben.m.sanders+kvm@gmail.com>]

I'm looking to reproduce the results of Alexander Graf earlier this
year when he said that he was able to get ESX to run a ReactOS guest
all on top of KVM.  More information on that can be found here:
http://kerneltrap.org/mailarchive/linux-kvm/2009/1/5/4600354/thread

So far, I can only boot esx into service console mode, not regular
mode or debug mode without a kernel panic (in ESX).  I've enabled
nesting, both in the module and in the kvm command on v86, using the
-cpu phenom option as well.

First question is about cpu type.  I've been using some dual core AMD
cpu's with svm enabled, but I'm wondering if I actually need a phenom
cpu for all of this to work.  I was under the impression that KVM/QEMU
could emulate a different CPU if the features didn't exist.

Second question is about the host OS.  Are the nesting features in KVM
only supported in an x86 OS? or should x86_64 work as well?  I've
tried each (in varying degrees), but if one implementation wouldn't
work (like emulating a phenom, an x86_64 processor on an x86 host OS),
I'd like to know so I can stay away from that.  Also, I've been using
Ubuntu 8.10 and 9.04, but if there's some reason I should switch to a
different distribution, I'd like to know that as well.

Thanks for your help