commit cce4517f upstream.

alloc_task_struct_node() allocates THREAD_SIZE and maintains some
weird refcount in the allocated memory. This never blew up as
task_struct size on 32bit machines was always less than THREAD_SIZE

Allocate just sizeof(struct task_struct) and get rid of the magic
refcounting.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120503085033.898475542@linutronix.de
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>