It is not harmless. I am also getting file system full errors. For example, Mozilla Firefox, can't download anything since it can't store any temp files.
$ df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_local-root 19G 19G 0 100% / none 5.9G 280K 5.9G 1% /dev none 5.9G 1.3M 5.9G 1% /dev/shm none 5.9G 468K 5.9G 1% /var/run none 5.9G 0 5.9G 0% /var/lock none 5.9G 0 5.9G 0% /lib/init/rw none 19G 19G 0 100% /var/lib/ureadahead/debugfs /dev/sda1 457M 116M 317M 27% /boot /dev/mapper/vg_local-home 159G 47G 105G 31% /home -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/499773 Title: Race with ureadahead can mean that /var/lib/ureadahead/debugfs appears in /etc/mtab To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mountall/+bug/499773/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs