Could you also include the output for 'sudo fdisk -l' or 'sudo parted -l' ?
There is just one thing I'm not sure I understand properly. Are there any adverse side-effects encountered as you run dist-upgrade? Or is this bug only about the messages seen on the console but the upgrade process appears to complete successfully? It wasn't clear to me which was the case from the bug description. If it's just cosmetic, it's probably the PReP partition that is confusing things. We can work around this directly in grub. ** Changed in: grub2 (Ubuntu) Status: New => Incomplete ** Changed in: grub2 (Ubuntu) Importance: Undecided => High -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1416396 Title: Unknown file system warning messages during dist-upgrade operation To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1416396/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs