diff --git a/hw/arm/xilinx_zynq.c b/hw/arm/xilinx_zynq.c
index 66d0de139f..c57bbccb70 100644
--- a/hw/arm/xilinx_zynq.c
+++ b/hw/arm/xilinx_zynq.c
@@ -355,13 +355,17 @@ static void zynq_init(MachineState *machine)
 
 static void zynq_machine_class_init(ObjectClass *oc, void *data)
 {
+    static const char * const valid_cpu_types[] = {
+        ARM_CPU_TYPE_NAME("cortex-a9"),
+        NULL
+    };
     MachineClass *mc = MACHINE_CLASS(oc);
     mc->desc = "Xilinx Zynq Platform Baseboard for Cortex-A9";
     mc->init = zynq_init;
     mc->max_cpus = 1;
     mc->no_sdcard = 1;
     mc->ignore_memory_transaction_failures = true;
-    mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-a9");
+    mc->valid_cpu_types = valid_cpu_types;
     mc->default_ram_id = "zynq.ext_ram";
 }