From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Kiszka <jan.kiszka@siemens.com>
Subject: Re: drop -enable-nesting
Date: Mon, 30 May 2011 17:04:02 +0200
Message-ID: <4DE3B1E2.7020006@siemens.com>
References: <4DDAD5CF.5050805@redhat.com> <4DE0B4B1.1000407@web.de>
	<20110530081847.GC27062@amd.com> <4DE3A3EC.80201@siemens.com>
	<20110530143846.GA2957@fermat.math.technion.ac.il>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-8-I
Content-Transfer-Encoding: quoted-printable
Cc: john cooper <john.cooper@redhat.com>, "Roedel,
	Joerg" <Joerg.Roedel@amd.com>, Anthony Liguori <aliguori@us.ibm.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, kvm <kvm@vger.kernel.org>
To: "Nadav Har'El" <nyh@math.technion.ac.il>
Return-path: <qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org>
In-Reply-To: <20110530143846.GA2957@fermat.math.technion.ac.il>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: </archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org
Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org
List-Id: kvm.vger.kernel.org

On 2011-05-30 16:38, Nadav Har'El wrote:
> On Mon, May 30, 2011, Jan Kiszka wrote about "drop -enable-nesting (was=
: [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 behavi=
or
>>>> 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 thing
>>> which can be wiped out.
>=20
> "-enable-nesting" could remain as a synonym for enabling either VMX or =
SVM
> in the guest, depending on what was available in the host (because KVM =
now
> supports both nested SVM and nested VMX, but not SVM-on-VMX or vice ver=
sa).

Why? Once nesting is stable (I think SVM already is), there is no reason
for an explicit enable. And you can always mask it out via -cpu.

BTW, what are the defaults for SVM right now in qemu-kvm and upstream?
Enable if the modeled CPU supports it?

Jan

--=20
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux