I had a network problem with KVM (natted network would not start after the
upgrade) and so I made the change to apparmor. This did not correct my
network problem and I had to delete and recreate the network in the GUI. So
I'm not 100% sure if it's related or not but the error message disapeared
Public bug reported:
Upgraded system from 13.04 to 13.10 64 bits with KVM installed before
upgrade. In /var/log/syslog, KVM complains at boot time :
apparmor=DENIED operation=capable parent=1
profile=/usr/sbin/libvirtd pid=1396 comm=libvirtd pid=1396
comm=libvirtd capability=29