I've received a response from a developer that the "BTRFS error" in the upstream kernel is intended behaviour. The kernel BUG in precise and the kernel Oops in quantal are not intended, therefore I've changed the tags from kernel-bug-exists-upstream to kernel-fixed-upstream.
** Tags removed: kernel-bug-exists-upstream ** Tags added: kernel-fixed-upstream -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1164336 Title: kernel BUG at /build/buildd/linux-3.2.0/fs/btrfs/transaction.c:1337! To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1164336/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs