cpumask: fix CONFIG_NUMA=y sched.c

Impact: fix panic on ia64 with NR_CPUS=1024

struct sched_domain is now a dangling structure; where we really want
static ones, we need to use static_sched_domain.

(As the FIXME in this file says, cpumask_var_t would be better, but
this code is hairy enough without trying to add initialization code to
the right places).
Reported-by: Mike Travis <travis@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -7282,10 +7282,10 @@ cpu_to_phys_group(int cpu, const struct cpumask *cpu_map,
  * groups, so roll our own. Now each node has its own list of groups which
  * gets dynamically allocated.
  */
-static DEFINE_PER_CPU(struct sched_domain, node_domains);
+static DEFINE_PER_CPU(struct static_sched_domain, node_domains);
 static struct sched_group ***sched_group_nodes_bycpu;
 
-static DEFINE_PER_CPU(struct sched_domain, allnodes_domains);
+static DEFINE_PER_CPU(struct static_sched_domain, allnodes_domains);
 static DEFINE_PER_CPU(struct static_sched_group, sched_group_allnodes);
 
 static int cpu_to_allnodes_group(int cpu, const struct cpumask *cpu_map,
@@ -7560,7 +7560,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
 #ifdef CONFIG_NUMA
 		if (cpumask_weight(cpu_map) >
 				SD_NODES_PER_DOMAIN*cpumask_weight(nodemask)) {
-			sd = &per_cpu(allnodes_domains, i);
+			sd = &per_cpu(allnodes_domains, i).sd;
 			SD_INIT(sd, ALLNODES);
 			set_domain_attribute(sd, attr);
 			cpumask_copy(sched_domain_span(sd), cpu_map);
@@ -7570,7 +7570,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
 		} else
 			p = NULL;
 
-		sd = &per_cpu(node_domains, i);
+		sd = &per_cpu(node_domains, i).sd;
 		SD_INIT(sd, NODE);
 		set_domain_attribute(sd, attr);
 		sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
@@ -7688,7 +7688,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
 		for_each_cpu(j, nodemask) {
 			struct sched_domain *sd;
 
-			sd = &per_cpu(node_domains, j);
+			sd = &per_cpu(node_domains, j).sd;
 			sd->groups = sg;
 		}
 		sg->__cpu_power = 0;