From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56434) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bCS5A-0000Ib-FW for qemu-devel@nongnu.org; Mon, 13 Jun 2016 09:39:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bCS56-0006ud-91 for qemu-devel@nongnu.org; Mon, 13 Jun 2016 09:39:12 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:30384 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bCS56-0006uX-4M for qemu-devel@nongnu.org; Mon, 13 Jun 2016 09:39:08 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u5DDcsfl129633 for ; Mon, 13 Jun 2016 09:39:07 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0a-001b2d01.pphosted.com with ESMTP id 23geh37n63-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 13 Jun 2016 09:39:07 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 13 Jun 2016 14:39:05 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (d06relay10.portsmouth.uk.ibm.com [9.149.109.195]) by d06dlp02.portsmouth.uk.ibm.com (Postfix) with ESMTP id BF2A7219006A for ; Mon, 13 Jun 2016 14:38:34 +0100 (BST) Received: from d06av07.portsmouth.uk.ibm.com (d06av07.portsmouth.uk.ibm.com [9.149.37.248]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u5DDd2sD14025038 for ; Mon, 13 Jun 2016 13:39:02 GMT Received: from d06av07.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av07.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u5DDd2Ii009479 for ; Mon, 13 Jun 2016 09:39:02 -0400 Received: from dyn-9-152-224-56.boeblingen.de.ibm.com (dyn-9-152-224-56.boeblingen.de.ibm.com [9.152.224.56]) by d06av07.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id u5DDd25M009460 for ; Mon, 13 Jun 2016 09:39:02 -0400 From: Guenther Hutzl Date: Mon, 13 Jun 2016 15:39:02 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Message-Id: Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] Should migration with slirp networking (-netdev user) be backward compatible? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Hello! I have a problem with migration from qemu-v2.6.0 to qemu-v2.5.0. It looks= like the slirp networking (-netdev user) is not backward compatible. This is t= he output I am seeing on the receiving side: qemu-system-x86_64: savevm: unsupported version 4 for 'slirp' v3 qemu-system-x86_64: load of migration failed: Invalid argument This is the little test machine I am trying to migrate (using tiny core l= inux iso): qemu-system-x86_64-2.6.0 -machine pc-i440fx-2.5 \ -m 512 \ -cdrom core-current.iso \ -boot d \ -nographic \ -curses \ -netdev user,id=3Dmynet0 \ -device virtio-net,netdev=3Dmynet0,id=3Dnet0 The target machine looks like this: qemu-system-x86_64-2.5.0 -machine pc-i440fx-2.5 \ -m 512 \ -cdrom core-current.iso \ -boot d \ -nographic \ -curses \ -netdev user,id=3Dmynet0 \ -device virtio-net,netdev=3Dmynet0,id=3Dnet0 \ -incoming tcp:0:4444 I am selecting a v2.5-compatible machine so migration to qemu-2.5 should = be possible. The question is: Is the migration of slirp networking backward compatible or is this unsupported for some reason? I tested migration from v2.6 to v2.6 with this configuration and it worke= d. Thank you, Guenther Hutzl. IBM Deutschland Research & Development GmbH Vorsitzende des Aufsichtsrats: Martina Koederitz Gesch=C3=A4ftsf=C3=BChrung: Dirk Wittkopp Sitz der Gesellschaft: B=C3=B6blingen Registergericht: Amtsgericht Stuttgart, HRB 243294