For copy_one_pte's print_bad_pte to show the task correctly (instead of
"???"), dup_mmap must pass down parent vma rather than child vma.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>