From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Chmielewski Subject: why guests show "Clocksource tsc unstable" on bootup? Date: Mon, 09 Mar 2009 13:01:15 +0100 Message-ID: <49B5050B.9050204@wpkg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit To: "kvm@vger.kernel.org" Return-path: Received: from mx03.syneticon.net ([78.111.66.105]:37141 "EHLO mx03.syneticon.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750789AbZCIMBW (ORCPT ); Mon, 9 Mar 2009 08:01:22 -0400 Received: from localhost (filter1.syneticon.net [192.168.113.83]) by mx03.syneticon.net (Postfix) with ESMTP id 4458D36146 for ; Mon, 9 Mar 2009 13:01:19 +0100 (CET) Received: from mx03.syneticon.net ([192.168.113.84]) by localhost (mx03.syneticon.net [192.168.113.83]) (amavisd-new, port 10025) with ESMTP id KR-XWiPZeoAy for ; Mon, 9 Mar 2009 13:01:16 +0100 (CET) Received: from [192.168.10.145] (koln-4db4063e.pool.einsundeins.de [77.180.6.62]) by mx03.syneticon.net (Postfix) with ESMTPSA for ; Mon, 9 Mar 2009 13:01:16 +0100 (CET) Sender: kvm-owner@vger.kernel.org List-ID: Why do my guests show "Clocksource tsc unstable" on bootup? dmesg shows that kvm-clock was set as the primary cpu clock. Yet a bit later kernel says "Clocksource tsc unstable". Is it something to worry about, or perhaps calculating tsc is hardcoded? And as such, will be always checked? Or, is it host CPU related? [ 0.000000] kvm-clock: cpu 0, msr 0:3baf81, boot clock [ 0.000000] kvm-clock: cpu 0, msr 0:1208f81, primary cpu clock [ 0.000000] Kernel command line: root=/dev/vda1 ro quiet clocksource=kvm-clock [ 1.253602] rtc_cmos 00:01: setting system clock to 2009-03-09 11:41:30 UTC (1236598890) [ 41.500623] Clocksource tsc unstable (delta = -153498948 ns) -- Tomasz Chmielewski http://wpkg.org