From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: unhandled wrmsr Date: Wed, 3 Nov 2010 11:51:57 -0200 Message-ID: <20101103135157.GA20269@amt.cnet> References: <1288638813.24358.17.camel@corn.betterworld.us> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org To: Ross Boylan Return-path: Received: from mx1.redhat.com ([209.132.183.28]:4345 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752617Ab0KCQ2n (ORCPT ); Wed, 3 Nov 2010 12:28:43 -0400 Content-Disposition: inline In-Reply-To: <1288638813.24358.17.camel@corn.betterworld.us> Sender: kvm-owner@vger.kernel.org List-ID: On Mon, Nov 01, 2010 at 12:13:33PM -0700, Ross Boylan wrote: > I built from qemu-kvm-0.13.0.tar.gz on a Debian system with kernel > linux-image-2.6.32-5-amd64 2.6.32-26 > (but otherwise basically the stable/lenny version) and now see > Oct 26 16:57:38 markov kernel: [ 5757.672426] kvm: 23063: cpu0 unhandled wrmsr: 0x198 data 0 > Oct 26 16:57:38 markov kernel: [ 5757.672454] kvm: 23063: cpu1 unhandled wrmsr: 0x198 data 0 > Oct 26 16:57:38 markov kernel: [ 5757.672476] kvm: 23063: cpu2 unhandled wrmsr: 0x198 data 0 > Oct 26 16:57:38 markov kernel: [ 5757.672497] kvm: 23063: cpu3 unhandled wrmsr: 0x198 data 0 > on startup. I have 4 CPUs with 8 cores: > Intel(R) Xeon(R) CPU E5420 @ 2.50GHz stepping 06. > Note this means the kernel side is from the Debian package, and so might > be older. > > google shows this message has popped up several times in the past and > been fixed several times. Most of the messages indicate it is harmless, > but https://bugs.launchpad.net/ubuntu/+source/linux/+bug/325851 on > 2009-07-01 says it's "not benign". There also seems to be a current bug > open about it, > http://sourceforge.net/tracker/index.php?func=detail&aid=3056363&group_id=180599&atid=893831, which is also marked as fixed. > > Can anyone tell me anything more about these messages? Do they indicate > a problem I need to fix? If so, any advice on how to fix it? Its harmless. KVM included MSR_IA32_PERF_STATUS (0x198) in the msr save/restore list, but there is no write emulation for it, which generates the warning.