From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH] kvm: fix cpuid eax
Date: Mon, 30 Apr 2012 13:40:34 -0700
Message-ID: <4F9EF8C2.7030103@zytor.com>
References: <20120430143902.GA10181@redhat.com> <4F9EF7FA.3060007@codemonkey.ws>
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Cc: "Michael S. Tsirkin" <mst@redhat.com>, Avi Kivity <avi@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org, davej@redhat.com
To: Anthony Liguori <anthony@codemonkey.ws>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <4F9EF7FA.3060007@codemonkey.ws>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

On 04/30/2012 01:37 PM, Anthony Liguori wrote:
> On 04/30/2012 09:39 AM, Michael S. Tsirkin wrote:
>> cpuid eax should return the max leaf so that
>> guests can find out the valid range.
>> This matches Xen et al.
> 
> What KVM does here predates Xen and Hyper-V.
> 
> This is an ABI breaker.
> 

What Intel and AMD have done here predates KVM...

What exactly relies on a zero here?

	-hpa