diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 6d0d31651f0515ed8cb78dffc2aa84609e807e49..5dc8f8028d520b6c0a09dd4e0a6ffb70d4891d84 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -313,6 +313,10 @@ config ARCH_SPARSEMEM_DEFAULT
 config ARCH_SELECT_MEMORY_MODEL
        def_bool y
 
+config ARCH_ENABLE_MEMORY_HOTPLUG
+	def_bool y
+	depends on SPARSEMEM
+
 source "mm/Kconfig"
 
 comment "I/O subsystem configuration"
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 05598649b3260f8689845ea2815914ffdd08e902..388cc742005544b05747d32a485e88c5c37cf5a6 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -202,3 +202,22 @@ void free_initrd_mem(unsigned long start, unsigned long end)
         }
 }
 #endif
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+int arch_add_memory(int nid, u64 start, u64 size)
+{
+	struct pglist_data *pgdat;
+	struct zone *zone;
+	int rc;
+
+	pgdat = NODE_DATA(nid);
+	zone = pgdat->node_zones + ZONE_NORMAL;
+	rc = vmem_add_mapping(start, size);
+	if (rc)
+		return rc;
+	rc = __add_pages(zone, PFN_DOWN(start), PFN_DOWN(size));
+	if (rc)
+		vmem_remove_mapping(start, size);
+	return rc;
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/include/asm-s390/sparsemem.h b/include/asm-s390/sparsemem.h
index 06dfdab6c0e8412a305c1e2bbfba03354dd30176..545d219e6a2d0d4e5dec734d7dc1d55f2906dd72 100644
--- a/include/asm-s390/sparsemem.h
+++ b/include/asm-s390/sparsemem.h
@@ -1,15 +1,15 @@
 #ifndef _ASM_S390_SPARSEMEM_H
 #define _ASM_S390_SPARSEMEM_H
 
-#define SECTION_SIZE_BITS	25
-
 #ifdef CONFIG_64BIT
 
+#define SECTION_SIZE_BITS	28
 #define MAX_PHYSADDR_BITS	42
 #define MAX_PHYSMEM_BITS	42
 
 #else
 
+#define SECTION_SIZE_BITS	25
 #define MAX_PHYSADDR_BITS	31
 #define MAX_PHYSMEM_BITS	31
 
diff --git a/mm/Kconfig b/mm/Kconfig
index 3aa819d628c112cc185f9545c7ae5e3fb8a5c310..4242743b981bcd2e8a864e43769831701e0fa44c 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -129,7 +129,7 @@ config MEMORY_HOTPLUG
 	bool "Allow for memory hot-add"
 	depends on SPARSEMEM || X86_64_ACPI_NUMA
 	depends on HOTPLUG && !HIBERNATION && ARCH_ENABLE_MEMORY_HOTPLUG
-	depends on (IA64 || X86 || PPC64 || SUPERH)
+	depends on (IA64 || X86 || PPC64 || SUPERH || S390)
 
 comment "Memory hotplug is currently incompatible with Software Suspend"
 	depends on SPARSEMEM && HOTPLUG && HIBERNATION