Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755954AbZCPMq5 (ORCPT ); Mon, 16 Mar 2009 08:46:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752257AbZCPMqs (ORCPT ); Mon, 16 Mar 2009 08:46:48 -0400 Received: from bowden.ucwb.org.au ([203.122.237.119]:49044 "EHLO mail.ucwb.org.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751101AbZCPMqr (ORCPT ); Mon, 16 Mar 2009 08:46:47 -0400 Subject: Re: [Bug #12465] KVM guests stalling on 2.6.28 (bisected) From: Kevin Shanahan To: Avi Kivity Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Ingo Molnar , Mike Galbraith , Peter Zijlstra In-Reply-To: <49BE20B2.9070804@redhat.com> References: <9nR7rAsBwYG.A.iEG.fOCvJB@chimera> <1237107837.27699.27.camel@kulgan.wumi.org.au> <49BE20B2.9070804@redhat.com> Content-Type: text/plain Organization: UnitingCare Wesley Bowden Date: Mon, 16 Mar 2009 23:16:35 +1030 Message-Id: <1237207595.4964.31.camel@kulgan.wumi.org.au> Mime-Version: 1.0 X-Mailer: Evolution 2.24.5 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2315 Lines: 61 On Mon, 2009-03-16 at 11:49 +0200, Avi Kivity wrote: > Kevin Shanahan wrote: > > On Sat, 2009-03-14 at 20:20 +0100, Rafael J. Wysocki wrote: > > > >> This message has been generated automatically as a part of a report > >> of regressions introduced between 2.6.27 and 2.6.28. > >> > >> The following bug entry is on the current list of known regressions > >> introduced between 2.6.27 and 2.6.28. Please verify if it still should > >> be listed and let me know (either way). > >> > >> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12465 > >> Subject : KVM guests stalling on 2.6.28 (bisected) > >> Submitter : Kevin Shanahan > >> Date : 2009-01-17 03:37 (57 days old) > >> Handled-By : Avi Kivity > >> > > > > No further updates since the last reminder. > > The bug should still be listed. > > Does the bug reproduce if you use the acpi_pm clocksource in the guests? In the guest being pinged? Yes, it still happens. hermes-old:~# cat /sys/devices/system/clocksource/clocksource0/available_clocksource kvm-clock acpi_pm jiffies tsc hermes-old:~# cat /sys/devices/system/clocksource/clocksource0/current_clocksource acpi_pm kmshanah@flexo:~$ ping -c 600 hermes-old --- hermes-old.wumi.org.au ping statistics --- 600 packets transmitted, 600 received, 0% packet loss, time 599439ms rtt min/avg/max/mdev = 0.131/723.197/9941.884/1569.918 ms, pipe 10 I had to reconfigure the guest kernel to make that clocksource available. The way I had the guest kernel configured before, it only had tsc and jiffies clocksources available. Unstable TSC was detected, so it has been using jiffies until now. Here's another test, using kvm-clock as the guest's clocksource: hermes-old:~# cat /sys/devices/system/clocksource/clocksource0/current_clocksource kvm-clock kmshanah@flexo:~$ ping -c 600 hermes-old --- hermes-old.wumi.org.au ping statistics --- 600 packets transmitted, 600 received, 0% packet loss, time 599295ms rtt min/avg/max/mdev = 0.131/1116.170/30840.411/4171.905 ms, pipe 31 Regards, Kevin. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/