While debugging a broken fs we were seeing hangs in the rb_erase loops. The
rbtree was simple and wasn't corrupted so it appeared to be a bug in our rbtree
library. Updating to the kernels latest rbtree code made the infinite loop go
away, so pull it back. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.cz>