diff --git a/arch/s390/include/asm/sysinfo.h b/arch/s390/include/asm/sysinfo.h
index 229326c942c7..27394989073a 100644
--- a/arch/s390/include/asm/sysinfo.h
+++ b/arch/s390/include/asm/sysinfo.h
@@ -142,7 +142,6 @@ struct sysinfo_3_2_2 {
 
 extern int topology_max_mnest;
 
-#define TOPOLOGY_CORE_BITS	64
 #define TOPOLOGY_NR_MAG		6
 
 struct topology_core {
@@ -152,7 +151,7 @@ struct topology_core {
 	unsigned char pp:2;
 	unsigned char reserved1;
 	unsigned short origin;
-	unsigned long mask[TOPOLOGY_CORE_BITS / BITS_PER_LONG];
+	unsigned long mask;
 };
 
 struct topology_container {
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index 17660e800e74..0537130fb915 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -83,6 +83,8 @@ static cpumask_t cpu_thread_map(unsigned int cpu)
 	return mask;
 }
 
+#define TOPOLOGY_CORE_BITS	64
+
 static void add_cpus_to_mask(struct topology_core *tl_core,
 			     struct mask_info *drawer,
 			     struct mask_info *book,
@@ -91,7 +93,7 @@ static void add_cpus_to_mask(struct topology_core *tl_core,
 	struct cpu_topology_s390 *topo;
 	unsigned int core;
 
-	for_each_set_bit(core, &tl_core->mask[0], TOPOLOGY_CORE_BITS) {
+	for_each_set_bit(core, &tl_core->mask, TOPOLOGY_CORE_BITS) {
 		unsigned int rcore;
 		int lcpu, i;