From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexander Graf <agraf@suse.de>
Subject: Re: kvm and cpu type
Date: Thu, 22 Jan 2009 14:43:06 +0100
Message-ID: <497877EA.8050305@suse.de>
References: <4978719F.1000007@cnaf.infn.it>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: kvm@vger.kernel.org
To: Riccardo Veraldi <Riccardo.Veraldi@cnaf.infn.it>
Return-path: <kvm-owner@vger.kernel.org>
Received: from mx1.suse.de ([195.135.220.2]:54680 "EHLO mx1.suse.de"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1752689AbZAVNnI (ORCPT <rfc822;kvm@vger.kernel.org>);
	Thu, 22 Jan 2009 08:43:08 -0500
In-Reply-To: <4978719F.1000007@cnaf.infn.it>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

Riccardo Veraldi wrote:
> Hello Iam using kvm83 on CentOS5.2
>
> my system has 2x dual Core intel CPU
>
> Intel(R) Xeon(R) CPU            5110  @ 1.60GHz
>
> asdetected by Centos.
>
> If I start kvm-qemu with no CPU option everythign works and hte guest
> machine detects cpu as
>
> QEMU Virtual CPU version 0.9.1
>
>
> iv I run qemu-kvm -cpu core2duo
>
> the guest hangs at boot time when it detects the CPU.
>
> I do not know how to fix it.
>
> I also do not know if using -cpu swtch can improve performances.

Yes, -cpu core*duo is broken in kvm < 84. Please use the default.
There's usually no real benefit for anyone to use a specific cpu type,
unless you know that you need it.

Alex