This seems to be a pretty good workaround allowing manual override of the root device. Simply drop a GRUB_DEVICE=/dev/... line into /etc/default/grub and things should just work again. Certainly not a permanent solution, but then again btrfs has quite a while until it sees usage outside of testing.
** Patch added: "Workaround patch" http://launchpadlibrarian.net/40446467/999_btrfs_workaround.diff -- grub-probe fails with btrfs root (and ext3 /boot) https://bugs.launchpad.net/bugs/450260 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs