diff --git a/arch/s390/include/asm/sparsemem.h b/arch/s390/include/asm/sparsemem.h
index c549893602ea..ff628c50afac 100644
--- a/arch/s390/include/asm/sparsemem.h
+++ b/arch/s390/include/asm/sparsemem.h
@@ -2,7 +2,7 @@
 #ifndef _ASM_S390_SPARSEMEM_H
 #define _ASM_S390_SPARSEMEM_H
 
-#define SECTION_SIZE_BITS	28
+#define SECTION_SIZE_BITS	27
 #define MAX_PHYSMEM_BITS	CONFIG_MAX_PHYSMEM_BITS
 
 #endif /* _ASM_S390_SPARSEMEM_H */