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From: Jan Kiszka <jan.kiszka@siemens.com>
To: "Nadav Har'El" <nyh@math.technion.ac.il>
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>
Subject: Re: drop -enable-nesting
Date: Mon, 30 May 2011 17:04:02 +0200	[thread overview]
Message-ID: <4DE3B1E2.7020006@siemens.com> (raw)
In-Reply-To: <20110530143846.GA2957@fermat.math.technion.ac.il>

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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:
>>>
>>>> Jörg, how to deal with -enable-nesting in qemu-kvm to align behavior
>>>> 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.
> 
> "-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 versa).

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

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

WARNING: multiple messages have this Message-ID (diff)
From: Jan Kiszka <jan.kiszka@siemens.com>
To: Nadav Har'El <nyh@math.technion.ac.il>
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>
Subject: Re: [Qemu-devel] drop -enable-nesting
Date: Mon, 30 May 2011 17:04:02 +0200	[thread overview]
Message-ID: <4DE3B1E2.7020006@siemens.com> (raw)
In-Reply-To: <20110530143846.GA2957@fermat.math.technion.ac.il>

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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:
>>>
>>>> Jörg, how to deal with -enable-nesting in qemu-kvm to align behavior
>>>> 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.
> 
> "-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 versa).

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

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

  reply	other threads:[~2011-05-30 15:04 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-23 21:46 [Qemu-devel] [PATCH 3/7] cpu model bug fixes and definition corrections: Add kvm emulated x2apic flag to config defined cpu models john cooper
2011-05-28  8:39 ` Jan Kiszka
2011-05-30  8:18   ` Roedel, Joerg
2011-05-30 14:04     ` drop -enable-nesting (was: [PATCH 3/7] cpu model bug fixes and definition corrections...) Jan Kiszka
2011-05-30 14:04       ` [Qemu-devel] " Jan Kiszka
2011-05-30 14:38       ` Nadav Har'El
2011-05-30 14:38         ` [Qemu-devel] " Nadav Har'El
2011-05-30 15:04         ` Jan Kiszka [this message]
2011-05-30 15:04           ` [Qemu-devel] drop -enable-nesting Jan Kiszka
2011-05-30 15:10           ` Roedel, Joerg
2011-05-30 15:10             ` [Qemu-devel] " Roedel, Joerg
2011-05-30 15:15             ` Jan Kiszka
2011-05-30 15:15               ` [Qemu-devel] " Jan Kiszka
2011-05-30 15:19               ` Avi Kivity
2011-05-30 15:19                 ` [Qemu-devel] " Avi Kivity
2011-05-30 15:27                 ` Jan Kiszka
2011-05-30 15:27                   ` [Qemu-devel] " Jan Kiszka
2011-05-30 15:42                   ` Jan Kiszka
2011-05-30 15:42                     ` [Qemu-devel] " Jan Kiszka
2011-05-31  8:44                 ` Daniel P. Berrange
2011-05-31  8:44                   ` [Qemu-devel] " Daniel P. Berrange
2011-05-31  8:58                   ` Avi Kivity
2011-05-31  8:58                     ` [Qemu-devel] " Avi Kivity
2011-05-31  9:06                     ` Roedel, Joerg
2011-05-31  9:06                       ` [Qemu-devel] " Roedel, Joerg
2011-05-31  9:15                     ` Paolo Bonzini
2011-05-31  9:15                       ` [Qemu-devel] " Paolo Bonzini
2011-05-31  9:16                       ` Avi Kivity
2011-05-31  9:16                         ` [Qemu-devel] " Avi Kivity
2011-05-30 15:16           ` Nadav Har'El
2011-05-30 15:16             ` [Qemu-devel] " Nadav Har'El
2011-05-30 15:59             ` Jan Kiszka
2011-05-30 15:59               ` [Qemu-devel] " Jan Kiszka

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