There are reports of this causing userspace failures
(http://lkml.org/lkml/2007/7/20/421).

Revert.

Cc: Jan Kratochvil <honza@jikos.cz>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Ulrich Kunitz <kune@deine-taler.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Bret Towe" <magnade@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>