The @ directory is a subvolume. Even if you don't need subvolumes at installation time (although the installer does create them in some cases, in order to support cunning tricks by update-manager later on), the way btrfs works is that you need to create at least one subvolume up-front otherwise you have to completely reorganise your filesystem if you ever need to use the feature in the future.
You can use 'mount -o subvol=@' to mount the appropriate subvolume. I'll give this another try in the coming week. The annoying thing is that GRUB's btrfs support works *some* of the time, and has stubbornly refused to fail when I'm trying to debug it. Could you please file a new bug on the grub2 package in Ubuntu (don't search for duplicates - I'd prefer a fresh bug report in this case), and describe exactly how you reproduced this bug? Ideally, I'd like something as close as possible to a recipe that I can use in a virtual machine. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/712029 Title: ubiquity btrfs install fails to boot (grub rescue> prompt) -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
