From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38469) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dsndX-0006HC-A2 for qemu-devel@nongnu.org; Fri, 15 Sep 2017 06:14:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dsndW-0008L7-82 for qemu-devel@nongnu.org; Fri, 15 Sep 2017 06:14:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42018) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dsndW-0008JR-30 for qemu-devel@nongnu.org; Fri, 15 Sep 2017 06:14:14 -0400 From: Cornelia Huck Date: Fri, 15 Sep 2017 12:14:05 +0200 Message-Id: <20170915101406.27823-1-cohuck@redhat.com> Subject: [Qemu-devel] [PATCH RFC 0/1] s390x: pci compat handling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: borntraeger@de.ibm.com, agraf@suse.de, thuth@redhat.com, david@redhat.com, pmorel@linux.vnet.ibm.com, zyimin@linux.vnet.ibm.com, pasic@linux.vnet.ibm.com, Cornelia Huck While playing around with compat machines a bit, I noticed that my zpci detanglement patches broke migration from 2.7 to current master (2.8 or newer are fine, which is why I did not notice that before.) qemu 2.7 seems to create a savevm that a s390-next (or master) build without the s390 phb chokes on: qemu-system-s390x: Unknown savevm section or instance 'PCIBUS' 0 Creating the s390 phb for compat machines seems to cure this; still RFC for the following reasons: - I'm not sure what we're supposed to do on builds without pci. Fail creating the compat machines? Do we need a new set of _NOPCI compat machines for that? - I don't understand why 2.7 fails, but 2.8 and later are fine. At least, I was not able to spot which commit changed the behaviour here... and I really want to understand this. Pointers welcome. - I have not tested it extensively yet. Patch is against s390-next. Cornelia Huck (1): s390x/ccw: create s390 phb for compat reasons as well hw/s390x/s390-virtio-ccw.c | 6 +++++- include/hw/s390x/s390-virtio-ccw.h | 1 + 2 files changed, 6 insertions(+), 1 deletion(-) -- 2.13.5