From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: [Qemu-devel] cpuid problem in upstream qemu with kvm
Date: Thu, 07 Jan 2010 05:39:23 -0600
Message-ID: <4B45C7EB.1010501@codemonkey.ws>
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Cc: Avi Kivity <avi@redhat.com>, kvm-devel <kvm@vger.kernel.org>,
	Gleb Natapov <gleb@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	John Cooper <john.cooper@redhat.com>,
	Alexander Graf <agraf@suse.de>, qemu-devel@nongnu.org
To: dlaor@redhat.com
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On 01/07/2010 03:40 AM, Dor Laor wrote:
>> There's no simple solution except to restrict features to what was
>> available on the first processors.
>
> What's not simple about the above 4 options?
> What's a better alternative (that insures users understand it and use 
> it and guest msi and even skype application is happy about it)?

Even if you have -cpu Nehalem, different versions of the KVM kernel 
module may additionally filter cpuid flags.

So if you had a 2.6.18 kernel and a 2.6.33 kernel, it may be necessary 
to say:

(2.6.33) qemu -cpu Nehalem,-syscall
(2.6.18) qemu -cpu Nehalem

In order to be compatible.

Regards,

Anthony Liguori