[PATCH] Fix: PowerNV crash with 4.4.0-rc8 at sched_init_numa

[Raghavendra K T]

Commit c118baf80256 ("arch/powerpc/mm/numa.c: do not allocate bootmem
memory for non existing nodes") avoided bootmem memory allocation for
non existent nodes.

When DEBUG_PER_CPU_MAPS enabled, powerNV system failed to boot because
in sched_init_numa, cpumask_or operation was done on unallocated nodes.
Fix that by making cpumask_or operation only on existing nodes.

[ Tested with and w/o DEBUG_PER_CPU_MAPS on x86 and powerpc ]

Reported-by: Jan Stancek <jstancek at redhat.com>
Signed-off-by: Raghavendra K T <raghavendra.kt at linux.vnet.ibm.com>
---
 kernel/sched/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 44253ad..474658b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6840,7 +6840,7 @@ static void sched_init_numa(void)
 
 			sched_domains_numa_masks[i][j] = mask;
 
-			for (k = 0; k < nr_node_ids; k++) {
+			for_each_node(k) {
 				if (node_distance(j, k) > sched_domains_numa_distance[i])
 					continue;
 
-- 
1.7.11.7