setup_new_group_blocks() manipulates the group descriptor block bh under
the block_bitmap bh's lock.  It shouldn't matter since nobody but resize
should be touching these blocks, but it's worth fixing up.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
C: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>