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Date: Mon, 06 Apr 2009 08:53:01 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 00/10] xen: pv domain support.
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To: Alexander Graf <agraf@suse.de>
Cc: xen-devel@lists.xensource.com, Laurent Vivier <Laurent@vivier.eu>, qemu-devel <qemu-devel@nongnu.org>

Alexander Graf wrote:
> One idea I had for full virtualization in a Xen environment would be an
> PV vmenter/vmexit framework - either by implementing a completely new
> abstraction or simple traps for privileged operations like VMRUN.
>
> That way we could have a kvm that talks to xen for the VM, rendering kvm
> useful on Xen dom0s, giving people the best of both worlds.

Hmm.  I suspect xen's direct paging mode makes that quite intrusive as
the kvm mmu code would have to know about this extra p2m translation
step to get the shadow/ept/ntp tables right.  Given that this most
likely would be a odd and rarely tested use case I don't think this
would be a good idea ...

cheers,
  Gerd