constrained_alloc(), which is called to detect where oom is from, checks
passed zone_list().  If zone_list doesn't include all nodes, it thinks oom
is from mempolicy.

But there is memory-less-node.  memory-less-node's zones are never included
in zonelist[].

contstrained_alloc() should get memory_less_node into count.  Otherwise, it
always thinks 'oom is from mempolicy'.  This means that current process
dies at any time.  This patch fix it.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>