diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c
index e09960744d..0eec0872a9 100644
--- a/hw/mem/memory-device.c
+++ b/hw/mem/memory-device.c
@@ -52,19 +52,30 @@ static int memory_device_build_list(Object *obj, void *opaque)
     return 0;
 }
 
-static void memory_device_check_addable(MachineState *ms, MemoryRegion *mr,
-                                        Error **errp)
+static unsigned int memory_device_get_memslots(MemoryDeviceState *md)
+{
+    const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
+
+    if (mdc->get_memslots) {
+        return mdc->get_memslots(md);
+    }
+    return 1;
+}
+
+static void memory_device_check_addable(MachineState *ms, MemoryDeviceState *md,
+                                        MemoryRegion *mr, Error **errp)
 {
     const uint64_t used_region_size = ms->device_memory->used_region_size;
     const uint64_t size = memory_region_size(mr);
+    const unsigned int required_memslots = memory_device_get_memslots(md);
 
-    /* we will need a new memory slot for kvm and vhost */
-    if (kvm_enabled() && !kvm_get_free_memslots()) {
-        error_setg(errp, "hypervisor has no free memory slots left");
+    /* we will need memory slots for kvm and vhost */
+    if (kvm_enabled() && kvm_get_free_memslots() < required_memslots) {
+        error_setg(errp, "hypervisor has not enough free memory slots left");
         return;
     }
-    if (!vhost_get_free_memslots()) {
-        error_setg(errp, "a used vhost backend has no free memory slots left");
+    if (vhost_get_free_memslots() < required_memslots) {
+        error_setg(errp, "a used vhost backend has not enough free memory slots left");
         return;
     }
 
@@ -233,7 +244,7 @@ void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms,
         goto out;
     }
 
-    memory_device_check_addable(ms, mr, &local_err);
+    memory_device_check_addable(ms, md, mr, &local_err);
     if (local_err) {
         goto out;
     }
diff --git a/include/hw/mem/memory-device.h b/include/hw/mem/memory-device.h
index 48d2611fc5..b51a579fb9 100644
--- a/include/hw/mem/memory-device.h
+++ b/include/hw/mem/memory-device.h
@@ -41,6 +41,11 @@ typedef struct MemoryDeviceState MemoryDeviceState;
  * successive memory regions are used, a covering memory region has to
  * be provided. Scattered memory regions are not supported for single
  * devices.
+ *
+ * The device memory region returned via @get_memory_region may either be a
+ * single RAM memory region or a memory region container with subregions
+ * that are RAM memory regions or aliases to RAM memory regions. Other
+ * memory regions or subregions are not supported.
  */
 struct MemoryDeviceClass {
     /* private */
@@ -88,6 +93,19 @@ struct MemoryDeviceClass {
      */
     MemoryRegion *(*get_memory_region)(MemoryDeviceState *md, Error **errp);
 
+    /*
+     * Optional for memory devices that require only a single memslot,
+     * required for all other memory devices: Return the number of memslots
+     * (distinct RAM memory regions in the device memory region) that are
+     * required by the device.
+     *
+     * If this function is not implemented, the assumption is "1".
+     *
+     * Called when (un)plugging the memory device, to check if the requirements
+     * can be satisfied, and to do proper accounting.
+     */
+    unsigned int (*get_memslots)(MemoryDeviceState *md);
+
     /*
      * Optional: Return the desired minimum alignment of the device in guest
      * physical address space. The final alignment is computed based on this