From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro@8bytes.org>
Subject: Re: Fwd: [PATCH 0/18] Nested Virtualization: Overview
Date: Sat, 17 Apr 2010 13:43:20 +0200
Message-ID: <20100417114320.GC23260@8bytes.org>
References: <201004151520.31527.Christoph.Egger@amd.com>
	<20100416090708.GA4224@ub-qhe2>
	<201004161132.25376.Christoph.Egger@amd.com>
	<20100416102711.GA31304@whitby.uk.xensource.com>
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To: Tim Deegan <Tim.Deegan@citrix.com>
Cc: Christoph Egger <Christoph.Egger@amd.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, Qing He <qing.he@intel.com>
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On Fri, Apr 16, 2010 at 11:27:11AM +0100, Tim Deegan wrote:
> At 10:32 +0100 on 16 Apr (1271413945), Christoph Egger wrote:

> Your PDFs suggest that even on Intel CPUs, the nested hypervisor should
> always see SVM, not VMX.  You shouldn't be surprised or offended if that
> isn't popular with Intel. :)

Well, it would make sense for Intel too virtualize SVM because it
doesn't has the performance issues with lots and lots of emulated
vmread/vmwrite instructions that cause vmexits in the nested case. The
bigger problem with SVM on VMX is that it could never be complete
because afaik VMX has fewer intercepts than SVM.

	Joerg