Comment # 6 on bug 1078498 from James Fehlig

> type=AVC msg=audit(1517402656.418:16535): apparmor="DENIED" operation="open" info="Failed name lookup - disconnected path" error=-13 profile="/usr/sbin/libvirtd" name="" pid=9072 comm="libvirtd" requested_mask="r" denied_mask="r" fsuid=0 ouid=0

This implies the libvirtd apparmor profile needs the 'attach_disconnected'
flag, but the 42.3 package should already have that. For more info see
https://bugzilla.opensuse.org/show_bug.cgi?id=1045158#c4

I recall someone else hitting a similar issue, which they resolved by nuking
the apparmor cache dir contents and restarting apparmor. Perhaps you also need
such drastic measure :-).