Comment 3 for bug 1546674

It seems that those Apparmor denials are responsible for severe slowdown of guests boot when the host boots up.

This simple fix makes the guests boot swiftly:

# diff -Naur /etc/apparmor.d/usr.lib.libvirt.virt-aa-helper.orig /etc/apparmor.d/usr.lib.libvirt.virt-aa-helper
--- /etc/apparmor.d/usr.lib.libvirt.virt-aa-helper.orig 2016-08-14 10:32:27.051646248 -0400
+++ /etc/apparmor.d/usr.lib.libvirt.virt-aa-helper 2016-08-14 10:32:20.019646323 -0400
@@ -66,4 +66,9 @@
   /**.vmdk r,
   /**.[iI][sS][oO] r,
   /**/disk{,.*} r,
+
+ # XXX: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1546674
+ /etc/hosts r,
+ /etc/host.conf r,
+ /etc/nsswitch.conf r,
 }