From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH] kvm: fix cpuid eax
Date: Tue, 01 May 2012 15:56:21 +0300
Message-ID: <4F9FDD75.4030608@redhat.com>
References: <20120430143902.GA10181@redhat.com> <4F9EF7FA.3060007@codemonkey.ws> <4F9FDCC4.3030302@redhat.com>
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Cc: "Michael S. Tsirkin" <mst@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	"H. Peter Anvin" <hpa@zytor.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: <4F9FDCC4.3030302@redhat.com>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

On 05/01/2012 03:53 PM, Avi Kivity wrote:
> On 04/30/2012 11:37 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.
>
> First, I don't think we ever documented eax, so nothing can rely on it.
>

Actually, we did document it.

However, I think it's safe to change.  The documentation in this case
should say "reserved, returns zero in this implementation", rather than 0.

-- 
error compiling committee.c: too many arguments to function