ogra@anubis:~/Devel/packages/initramfs-tools-ubuntu-core-0.7.11$ diff -ruN hooks/ubuntu-core-rootfs.orig hooks/ubuntu-core-rootfs
--- hooks/ubuntu-core-rootfs.orig	2015-10-19 13:47:20.805865365 +0200
+++ hooks/ubuntu-core-rootfs	2015-10-19 13:47:51.397866122 +0200
@@ -22,3 +22,5 @@
 copy_exec /bin/chown
 copy_exec /sbin/findfs
 copy_exec /sbin/e2fsck
+manual_add_modules squashfs
+manual_add_modules loop
ogra@anubis:~/Devel/packages/initramfs-tools-ubuntu-core-0.7.11$