From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Roedel, Joerg" <Joerg.Roedel@amd.com>
Subject: Re: drop -enable-nesting
Date: Tue, 31 May 2011 11:06:17 +0200
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Cc: "Daniel P. Berrange" <berrange@redhat.com>,
	Jan Kiszka <jan.kiszka@siemens.com>,
	Nadav Har'El <nyh@math.technion.ac.il>,
	john cooper <john.cooper@redhat.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
	Anthony Liguori <aliguori@us.ibm.com>,
	kvm <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On Tue, May 31, 2011 at 04:58:16AM -0400, Avi Kivity wrote:
> On 05/31/2011 11:44 AM, Daniel P. Berrange wrote:
> > >  I think it's safe to drop -enable-nesting immediately.  Dan, does
> > >  libvirt make use of it?
> >
> > Yes, but it should be safe to drop it. Currently, if the user specifies
> > a CPU with the 'svm' flag present in libvirt guest XML, then we will
> > pass args '-cpu ....+svm -enable-nesting'. So if we drop --enable-nesting,
> > then libvirt will simply omit it and everything should still work because
> > we have still got +svm set.
> 
> But qemu will complain about an option it can't parse.

The best choice is probably to keep the option and make it a nop for the
lifetime of qemu-kvm. Optionally qemu-kvm can print a warning about the
deprecated option.

	Joerg

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