From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josip Rodin Subject: Re: (XEN) Platform timer appears to have unexpectedly wrapped 10 or more times. Date: Tue, 10 Apr 2012 16:07:57 +0200 Message-ID: <20120410140757.GA24893@entuzijast.net> References: <20120104172343.GA30630@entuzijast.net> <4F84288E.1070407@hfp.de> <20120410130512.GA3598@entuzijast.net> <4F843CCE.7010307@hfp.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <4F843CCE.7010307@hfp.de> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andreas Kinzler Cc: Philippe.Simonet@swisscom.com, xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Tue, Apr 10, 2012 at 03:59:42PM +0200, Andreas Kinzler wrote: > >On Tue, Apr 10, 2012 at 02:33:18PM +0200, Andreas Kinzler wrote: > >>I have the same problem. Do you use ntpd? Which version? I suspect > >>some link between the problem and ntpd. > >But ntpd is still a userland program, shouldn't the kernel exert the > >ultimate control over who gets to screw with the system's clock source? > >In any case, I did a quick grep of ntpd sources and found references to > >RDTSC only in the Windows port, so the link doesn't seem obvious. > > Right, there is no obvious link (but which hard to reproduce bug is > obvious?) but see > "http://lists.xen.org/archives/html/xen-devel/2011-10/msg01269.html". > There seems to be some connection. >>From that (garbled) log, I don't see it - you didn't even post the matching kernel log message with timestamp, so it's impossible to see if and when it coincided when the ntpd messages. Over here we're running ntpd, obviously, in dom0 and in domU, but the only observed interaction of this problem with ntpd is that they become useless with this kind of a major drift. -- 2. That which causes joy or happiness.