[PATCH] Fix NULL pointer dereference in node_read_numastat()

zone_pcp() only returns valid values if the processor is online.

Change node_read_numastat() to only scan online processors.

Signed-off-by: Christoph Lameter <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/base/node.c

···
 	other_node = 0;
 	for (i = 0; i < MAX_NR_ZONES; i++) {
 		struct zone *z = &pg->node_zones[i];
-		for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		for_each_online_cpu(cpu) {
 			struct per_cpu_pageset *ps = zone_pcp(z,cpu);
 			numa_hit += ps->numa_hit;
 			numa_miss += ps->numa_miss;