From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel P. Berrange" Subject: Re: [Qemu-devel] qemu and qemu.git -> Migration + disk stress introduces qcow2 corruptions Date: Thu, 10 Nov 2011 20:06:09 +0000 Message-ID: <20111110200609.GB4941@redhat.com> References: <4EBAAA68.10801@redhat.com> <4EBAACAF.4080407@codemonkey.ws> <4EBAB236.2060409@redhat.com> <4EBAB9FA.3070601@codemonkey.ws> <4EBB919B.7040605@redhat.com> <4EBC1792.3030004@codemonkey.ws> <20111110184200.GC17987@redhat.com> <4EBC21EE.2010102@codemonkey.ws> Reply-To: "Daniel P. Berrange" Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Lucas Meneghel Rodrigues , Kevin Wolf , KVM mailing list , "Michael S. Tsirkin" , "libvir-list@redhat.com" , Marcelo Tosatti , QEMU devel , Juan Jose Quintela Carreira , Avi Kivity To: Anthony Liguori Return-path: Received: from mx1.redhat.com ([209.132.183.28]:7447 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752702Ab1KJUGZ (ORCPT ); Thu, 10 Nov 2011 15:06:25 -0500 Content-Disposition: inline In-Reply-To: <4EBC21EE.2010102@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Nov 10, 2011 at 01:11:42PM -0600, Anthony Liguori wrote: > On 11/10/2011 12:42 PM, Daniel P. Berrange wrote: > >On Thu, Nov 10, 2011 at 12:27:30PM -0600, Anthony Liguori wrote: > >>What does libvirt actually do in the monitor prior to migration > >>completing on the destination? The least invasive way of doing > >>delayed open of block devices is probably to make -incoming create a > >>monitor and run a main loop before the block devices (and full > >>device model) is initialized. Since this isolates the changes > >>strictly to migration, I'd feel okay doing this for 1.0 (although it > >>might need to be in the stable branch). > > > >The way migration works with libvirt wrt QEMU interactions is now > >as follows > > > > 1. Destination. > > Run qemu -incoming ...args... > > Query chardevs via monitor > > Query vCPU threads via monitor > > Set disk / vnc passwords > > Since RHEL carries Juan's patch, and Juan's patch doesn't handle > disk passwords gracefully, how does libvirt cope with that? No idea, that's the first I've heard of any patch that causes problems with passwords in QEMU. Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|