From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Roedel, Joerg" <Joerg.Roedel@amd.com>
Subject: Re: drop -enable-nesting
Date: Mon, 30 May 2011 17:10:20 +0200
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Cc: john cooper <john.cooper@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>,
	Nadav Har'El <nyh@math.technion.ac.il>, kvm <kvm@vger.kernel.org>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
To: Jan Kiszka <jan.kiszka@siemens.com>
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On Mon, May 30, 2011 at 11:04:02AM -0400, Jan Kiszka wrote:
> On 2011-05-30 16:38, Nadav Har'El wrote:
> > On Mon, May 30, 2011, Jan Kiszka wrote about "drop -enable-nesting (w=
as: [PATCH 3/7] cpu model bug fixes and definition corrections...)":
> >> On 2011-05-30 10:18, Roedel, Joerg wrote:
> >>> On Sat, May 28, 2011 at 04:39:13AM -0400, Jan Kiszka wrote:
> >>>
> >>>> J=F6rg, how to deal with -enable-nesting in qemu-kvm to align beha=
vior
> >>>> with upstream?
> >>>
> >>> My personal preference is to just remove it. In upstream-qemu it is
> >>> enabled/disabled by +/-svm. -enable-nesting is just a historic thin=
g
> >>> which can be wiped out.
> >=20
> > "-enable-nesting" could remain as a synonym for enabling either VMX o=
r SVM
> > in the guest, depending on what was available in the host (because KV=
M now
> > supports both nested SVM and nested VMX, but not SVM-on-VMX or vice v=
ersa).
>=20
> Why? Once nesting is stable (I think SVM already is), there is no reaso=
n
> for an explicit enable. And you can always mask it out via -cpu.
>=20
> BTW, what are the defaults for SVM right now in qemu-kvm and upstream?
> Enable if the modeled CPU supports it?

qemu-kvm still needs -enable-nesting, otherwise it is disabled. Upstream
qemu should enable it unconditionally (can be disabled with -cpu ,-svm).

	Joerg

--=20
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