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Date: Mon, 09 Sep 2013 19:29:36 +1000
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Subject: Re: [Qemu-devel] [RFC PATCH] spapr: support time base offset
	migration
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To: Alexander Graf <agraf@suse.de>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>, Paolo Bonzini <pbonzini@redhat.com>, Paul Mackerras <paulus@samba.org>, Andreas =?ISO-8859-1?Q?F=E4rber?= <afaerber@suse.de>, David Gibson <david@gibson.dropbear.id.au>

On Mon, 2013-09-09 at 08:06 +0200, Alexander Graf wrote:
> I think it's ok to restrict live migration to machines with the same
> tb frequency when kvm is enabled. Whether you implement it through a
> hardcoded 512Mhz or through a timebase value that gets live migrated
> and then compared is up to you - both ways work for me :).

The latter might be handy if we want to support migration on 970, though
we don't have the TBU40 stuff there so adjusting the TB in the host
kernel would be ... problematic.

Cheers,
Ben.