pgd_index(end + PGDIR_SIZE - 1) returns 0 if end + PGDIR_SIZE - 1 is beyond
the end of the address space.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>