On Tue, Apr 14, 2009 at 12:15:23PM +0300, Avi Kivity wrote:
Daniel P. Berrange wrote:
Yes indeed its a little crazy :-) As anthony mentioned if libvirt were able to be notified of changes a user makes in the monitor, there's no reason we could not allow end users to access the monitor of a VM libvirt is managing. We just need to make sure libvirt doesn't miss changes like attaching or detaching block devices, etc, because that'll cause crash/data loss later when libvirt migrates or does save/restore, etc because it'll launch QEMU with wrong args
You still have an inherent race here.
user: plug in disk libvirt: start migration, still without disk qemu: libvirt, a disk has been plugged in.
That is true, but we'd still be considering direct monitor access to be a 'expert' user mode of use. If they wish to shoot themselves in the foot by triggering a migration at same time they are hotplugging I'm fine if their whole leg gets blown away. Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|