From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philipp Hahn Subject: FYI: Upgrade from pc-0.12 / pc-014 vs. savevm section "kvmclock" Date: Fri, 23 Nov 2012 09:17:18 +0100 Message-ID: <201211230917.27560.hahn@univention.de> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1411021.h3DVQpg75U"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit To: "kvm@vger.kernel.org" , libvir-list@redhat.com Return-path: Received: from mail.univention.de ([82.198.197.8]:1298 "EHLO mail.univention.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754007Ab2KWIRd (ORCPT ); Fri, 23 Nov 2012 03:17:33 -0500 Sender: kvm-owner@vger.kernel.org List-ID: --nextPart1411021.h3DVQpg75U Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hello, I'm using libvirt to manage my KVM instances. I created a VM with=20 qemu-kvm-0.12, later upgraded to qemu-kvm-0.14 and took a snapshot using=20 libvirt. As the original VM was created with qemu-kvm-0.12, libvirt=20 stored "pc-0.12" with its XML data. Now I upgraded to qemu-kvm-1.1.2, where= =20 reverting to that snapshot fails with a the message > Unknown savevm section or instance 'kvmclock' 0 > load of migration failed I tracked that down to hw/pc_piix.c:590 where=20 > static QEMUMachine pc_machine_v0_12 =3D { > .name =3D "pc-0.12", > .desc =3D "Standard PC", > .init =3D pc_init_pci_no_kvmclock, is defined. If I change .init to pc_init_pci, I'm able to load the old=20 snapshot. I think this is because kvm-0.14 always created the kvmclock device, while= =20 that was only later changed (0ec329da) to be created "on demand" for pc-0.1= 4s=20 onward. So the snapshot is no longer a pure pc-0.12, but some=20 pc-0.12+something, which qemu-kvm-1.1.2 refuses to load. Now that I know what the problem is I just want to inform others, who might= =20 experience the same problem. My workaround is a patched qemu-kvm, where I=20 changed that .init mentioned above, since an additional enabled kvmclock do= es=20 not seem to do any harm. If someone has a better fix, I'm open to suggestions. Sincerely Philipp =2D-=20 Philipp Hahn Open Source Software Engineer hahn@univention.de Univention GmbH be open. fon: +49 421 22 232- 0 Mary-Somerville-Str.1 D-28359 Bremen fax: +49 421 22 232-99 http://www.univention.de/ --nextPart1411021.h3DVQpg75U Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAlCvMQ4ACgkQYPlgoZpUDjmzhwCcD8PFUb0+VKLt84ib/L/WUU7J c2oAn35dMQoUnHy5ajWgsV8VhZLCFE8v =WD6p -----END PGP SIGNATURE----- --nextPart1411021.h3DVQpg75U--