diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 8bfb6684cb..18ad279a00 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -154,39 +154,15 @@ static void virtio_ccw_register_hcalls(void)
                                    virtio_ccw_hcall_early_printk);
 }
 
-/*
- * KVM does only support memory slots up to KVM_MEM_MAX_NR_PAGES pages
- * as the dirty bitmap must be managed by bitops that take an int as
- * position indicator. If we have a guest beyond that we will split off
- * new subregions. The split must happen on a segment boundary (1MB).
- */
-#define KVM_MEM_MAX_NR_PAGES ((1ULL << 31) - 1)
-#define SEG_MSK (~0xfffffULL)
-#define KVM_SLOT_MAX_BYTES ((KVM_MEM_MAX_NR_PAGES * TARGET_PAGE_SIZE) & SEG_MSK)
 static void s390_memory_init(ram_addr_t mem_size)
 {
     MemoryRegion *sysmem = get_system_memory();
-    ram_addr_t chunk, offset = 0;
-    unsigned int number = 0;
+    MemoryRegion *ram = g_new(MemoryRegion, 1);
     Error *local_err = NULL;
-    gchar *name;
 
     /* allocate RAM for core */
-    name = g_strdup_printf("s390.ram");
-    while (mem_size) {
-        MemoryRegion *ram = g_new(MemoryRegion, 1);
-        uint64_t size = mem_size;
-
-        /* KVM does not allow memslots >= 8 TB */
-        chunk = MIN(size, KVM_SLOT_MAX_BYTES);
-        memory_region_allocate_system_memory(ram, NULL, name, chunk);
-        memory_region_add_subregion(sysmem, offset, ram);
-        mem_size -= chunk;
-        offset += chunk;
-        g_free(name);
-        name = g_strdup_printf("s390.ram.%u", ++number);
-    }
-    g_free(name);
+    memory_region_allocate_system_memory(ram, NULL, "s390.ram", mem_size);
+    memory_region_add_subregion(sysmem, 0, ram);
 
     /*
      * Configure the maximum page size. As no memory devices were created
diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
index 97a662ad0e..54864c259c 100644
--- a/target/s390x/kvm.c
+++ b/target/s390x/kvm.c
@@ -28,6 +28,7 @@
 #include "cpu.h"
 #include "internal.h"
 #include "kvm_s390x.h"
+#include "sysemu/kvm_int.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "qemu/timer.h"
@@ -122,6 +123,15 @@
  */
 #define VCPU_IRQ_BUF_SIZE(max_cpus) (sizeof(struct kvm_s390_irq) * \
                                      (max_cpus + NR_LOCAL_IRQS))
+/*
+ * KVM does only support memory slots up to KVM_MEM_MAX_NR_PAGES pages
+ * as the dirty bitmap must be managed by bitops that take an int as
+ * position indicator. If we have a guest beyond that we will split off
+ * new subregions. The split must happen on a segment boundary (1MB).
+ */
+#define KVM_MEM_MAX_NR_PAGES ((1ULL << 31) - 1)
+#define SEG_MSK (~0xfffffULL)
+#define KVM_SLOT_MAX_BYTES ((KVM_MEM_MAX_NR_PAGES * TARGET_PAGE_SIZE) & SEG_MSK)
 
 static CPUWatchpoint hw_watchpoint;
 /*
@@ -355,6 +365,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
      */
     /* kvm_vm_enable_cap(s, KVM_CAP_S390_AIS, 0); */
 
+    kvm_set_max_memslot_size(KVM_SLOT_MAX_BYTES);
     return 0;
 }