diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 3aeb2ead2a..0dba32fa2c 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1808,6 +1808,7 @@ static const TypeInfo spapr_machine_info = {
     .abstract      = true,
     .instance_size = sizeof(sPAPRMachineState),
     .instance_init = spapr_machine_initfn,
+    .class_size    = sizeof(sPAPRMachineClass),
     .class_init    = spapr_machine_class_init,
     .interfaces = (InterfaceInfo[]) {
         { TYPE_FW_PATH_PROVIDER },
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 785b0944d9..0aeac50eea 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -15,11 +15,26 @@ typedef struct sPAPREventLogEntry sPAPREventLogEntry;
 #define HPTE64_V_HPTE_DIRTY     0x0000000000000040ULL
 #define SPAPR_ENTRY_POINT       0x100
 
+typedef struct sPAPRMachineClass sPAPRMachineClass;
 typedef struct sPAPRMachineState sPAPRMachineState;
 
 #define TYPE_SPAPR_MACHINE      "spapr-machine"
 #define SPAPR_MACHINE(obj) \
     OBJECT_CHECK(sPAPRMachineState, (obj), TYPE_SPAPR_MACHINE)
+#define SPAPR_MACHINE_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(sPAPRMachineClass, obj, TYPE_SPAPR_MACHINE)
+#define SPAPR_MACHINE_CLASS(klass) \
+    OBJECT_CLASS_CHECK(sPAPRMachineClass, klass, TYPE_SPAPR_MACHINE)
+
+/**
+ * sPAPRMachineClass:
+ */
+struct sPAPRMachineClass {
+    /*< private >*/
+    MachineClass parent_class;
+
+    /*< public >*/
+};
 
 /**
  * sPAPRMachineState: