From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guido Winkelmann Subject: Re: I/O errors in guest OS after repeated migration Date: Tue, 06 Nov 2012 12:07:30 +0100 Message-ID: <2061347.nNjMkC6xtr@pc10> References: <4445323.hu543A05kM@pc10> <4171872.p5vXfS9P60@pc10> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: Avi Kivity , Brian Jackson , kvm@vger.kernel.org To: Stefan Hajnoczi Return-path: Received: from unknownsite.de ([62.48.69.106]:54823 "EHLO hartes-hannover.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750706Ab2KFLHf (ORCPT ); Tue, 6 Nov 2012 06:07:35 -0500 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: Am Montag, 29. Oktober 2012, 12:29:01 schrieb Stefan Hajnoczi: > On Fri, Oct 19, 2012 at 2:55 PM, Guido Winkelmann > wrote: > > Am Donnerstag, 18. Oktober 2012, 18:05:39 schrieb Avi Kivity: > >> On 10/18/2012 05:50 PM, Guido Winkelmann wrote: > >> > Am Mittwoch, 17. Oktober 2012, 13:25:45 schrieb Brian Jackson: > >> >> > >> >> What about newer versions of qemu/kvm? But of course if those work, > >> >> your > >> >> next task is going to be git bisect it or file a bug with your distro > >> >> that > >> >> is using an ancient version of qemu/kvm. > >> > > >> > I've just upgraded both hosts to qemu-kvm 1.2.0 > >> > (qemu-1.2.0-14.fc17.x86_64, > >> > built from spec files under > >> > http://pkgs.fedoraproject.org/cgit/qemu.git/). > >> > > >> > The bug is still there. > >> > >> If you let the guest go idle (no I/O), then migrate it, then restart the > >> I/O, do the errors show? > > > > Just tested - yes, they do. > > The -EIO error does not really reveal why there is a problem. You can > use SystemTap probes in QEMU to find out more about the nature of the > error. > > # stap -e 'probe qemu.kvm.bdrv_*, qemu.kvm.virtio_blk_*, > qemu.kvm.paio_* { printf("%s(%s)\n", probefunc(), $$parms) }' -x > $PID_OF_QEMU This does not work for me. When I try running this, I'm getting many pages of errors like this: ====== # stap -e 'probe qemu.kvm.bdrv_*, qemu.kvm.virtio_blk_*, qemu.kvm.paio_* { printf("%s(%s)\n", probefunc(), $$parms) }' -x 1623 parse error: expected statement saw: keyword at /usr/share/systemtap/tapset/qemu-alpha.stp:1455:3 source: function = $arg3; ^ parse error: expected identifier saw: operator '=' at /usr/share/systemtap/tapset/qemu- alpha.stp:1455:12 source: function = $arg3; ^ 2 parse errors. ====== Unfortunately, I don't know the first thing about systemtap, so I don't really know what's happening here... Guido