From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:33553)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1bAbiu-0005lr-5p
	for qemu-devel@nongnu.org; Wed, 08 Jun 2016 07:32:37 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1bAbip-0000kR-5R
	for qemu-devel@nongnu.org; Wed, 08 Jun 2016 07:32:36 -0400
Received: from mail-wm0-x241.google.com ([2a00:1450:400c:c09::241]:35935)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1bAbio-0000kC-G1
	for qemu-devel@nongnu.org; Wed, 08 Jun 2016 07:32:31 -0400
Received: by mail-wm0-x241.google.com with SMTP id m124so2214751wme.3
	for <qemu-devel@nongnu.org>; Wed, 08 Jun 2016 04:32:30 -0700 (PDT)
Sender: Paolo Bonzini <paolo.bonzini@gmail.com>
References: <20160603060944.17373-1-haozhong.zhang@intel.com>
	<20160603060944.17373-2-haozhong.zhang@intel.com>
	<20160603155753.GA15222@potion>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <10fb3041-9b08-ea31-a04d-76169313fc21@redhat.com>
Date: Wed, 8 Jun 2016 13:32:24 +0200
MIME-Version: 1.0
In-Reply-To: <20160603155753.GA15222@potion>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Subject: Re: [Qemu-devel] [PATCH v3 1/2] target-i386: KVM: add basic Intel
 LMCE support
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/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>
To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>, Haozhong Zhang <haozhong.zhang@intel.com>
Cc: qemu-devel@nongnu.org, Richard Henderson <rth@twiddle.net>, Eduardo Habkost <ehabkost@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>, "Michael S . Tsirkin" <mst@redhat.com>, kvm@vger.kernel.org, Boris Petkov <bp@suse.de>, Tony Luck <tony.luck@intel.com>, Andi Kleen <andi.kleen@intel.com>, Ashok Raj <ashok.raj@intel.com>



On 03/06/2016 17:57, Radim Krčmář wrote:
>> > +                cenv->msr_ia32_feature_control |=
>> > +                    MSR_IA32_FEATURE_CONTROL_LMCE |
>> > +                    MSR_IA32_FEATURE_CONTROL_LOCKED;
> Locking right from the start breaks nested KVM, because nested relies on
> setting VMXON feature from inside of the guest.
> 
> Do we keep it unlocked, or move everything into QEMU?
> 
> (The latter seems simpler.)

I think it should be moved into the firmware, with QEMU publishing the
desired setting via fw_cfg.  The same as what is done in real hardware,
that's the KVM mantra. :)

For v4 it's okay to just remove this.

Paolo