From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: [RFC] CPUID usage for interaction between Hypervisors and	Linux.
Date: Wed, 01 Oct 2008 11:06:25 -0700
Message-ID: <48E3BC21.4080803@goop.org>
References: <1222881242.9381.17.camel@alok-dev1>	 <48E3B19D.6060905@zytor.com> <1222882431.9381.23.camel@alok-dev1>
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Cc: "H. Peter Anvin" <hpa@zytor.com>,
	"avi@redhat.com" <avi@redhat.com>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Gerd Hoffmann <kraxel@redhat.com>, Ingo Molnar <mingo@elte.hu>,
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	LKML <linux-kernel@vger.kernel.org>,
	"Nakajima, Jun" <jun.nakajima@intel.com>,
	Daniel Hecht <dhecht@vmware.com>,
	Zach Amsden <zach@vmware.com>,
	"virtualization@lists.linux-foundation.org"
	<virtualization@lists.linux-foundation.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>
To: akataria@vmware.com
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Alok Kataria wrote:
> Its not a user who has to do anything special here.
> There are *intelligent* VM developers out there who can export a
> different CPUid interface depending on the guest OS type. And this is
> what most of the hypervisors do (not necessarily for CPUID, but for
> other things right now).
>   

No, that's always a terrible idea.  Sure, its necessary to deal with 
some backward-compatibility issues, but we should even consider a new 
interface which assumes this kind of thing.  We want properly enumerable 
interfaces.

    J