Clean up the stale DBUG_ON checks and add a couple new ones.
Signed-off-by: NRobin Holt <holt@sgi.com>
Signed-off-by: NDean Nelson <dcn@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>