I'm not sure why I haven't gotten any emails about this discussion in all this time. However (due to an independent report on github) this problem *should* be fixed as of 0.34-1. cgmanager now remounts / in its private ns as MS_SLAVE, not MS_PRIVATE, so the umount from the host should propagate into cgmanager's namespace.
If that does not suffice, we can add an option to cgmanager (and maybe even make it default) to not unshare a private namespace. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org