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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Wed, 20 Jun 2012 09:52:38 +1000
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Subject: Re: [Qemu-devel] vm state save/restore question
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To: Alexander Graf <agraf@suse.de>
Cc: "qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>, quintela@redhat.com

On Wed, 2012-06-20 at 01:30 +0200, Alexander Graf wrote:
> > We support the paravirtualized -M pseries in full emu as well, in which
> > case the hashed page table is handled by qemu itself who implements the
> > H_ENTER & co hypercalls. So it's very similar, except that qemu doesn't
> > have to ask the kernel to get a snapshot :-)
> > 
> > So I can flush out the storage format and two stage process inside qemu,
> > and then bother with the kvm/kernel interface.
> > 
> > Normal "bare metal" operation in qemu (or even KVM "PR") doesn't require
> > this as in that case the hash table is just a normal part of the guest
> > memory, it's only an issue when doing paravirtualized guest such as
> > pseries (aka PAPR).
> 
> IIRC we still allocate it outside of normal guest memory, so you don't get the migration for free :).

You haven't ready my post properly :-)

Cheers,
Ben.