Failed to get machine type in arm

cpu,qemu_vm,env_process: Judge machine type in supported machine types.
                         If not, will using default value 'virt'.

Current the param of machine type must be in format "xx:xx", otherwise
it will cause error "list index out of range".

virttest/cpu.py

@@ -1234,7 +1234,16 @@ def get_qemu_best_cpu_model(params):
     qemu_binary = utils_misc.get_qemu_binary(params)
     # aarch64 use 'qemu_binary -M machine_type -cpu ?' to get supported cpu models.
     if platform.machine() == 'aarch64':
-        machine_type = params.get("machine_type").split(':', 1)[1]
+        machine_type = params.get("machine_type")
+        if ':' in machine_type:
+            machine_type = machine_type.split(':', 1)[1]
+        # Needed to judge if machine_type supported in arm
+        hvm_or_pv = params.get("hvm_or_pv", "hvm")
+        from virttest.utils_test import libvirt
+        support_machine_type = libvirt.get_machine_types('aarch64', hvm_or_pv, ignore_status=False)
+        if machine_type not in support_machine_type:
+            logging.warn("Unsupported machine type %s", machine_type)
+            machine_type = 'virt'
         extra_params = " -M" + " %s" % machine_type
         qemu_cpu_models = get_qemu_cpu_models(qemu_binary, extra_params)
     else:

virttest/env_process.py

@@ -1038,7 +1038,17 @@ def preprocess(test, params, env):
         qemu_path = utils_misc.get_qemu_binary(params)
         # aarch64 use "qemu-kvm -M machine_type" instead.
         if platform.machine() == 'aarch64':
-            machine_type = params.get("machine_type").split(':', 1)[1]
+            machine_type = params.get("machine_type")
+            if ':' in machine_type:
+                machine_type = machine_type.split(':', 1)[1]
+            # Needed to judge if machine_type supported in arm
+            hvm_or_pv = params.get("hvm_or_pv", "hvm")
+            from virttest.utils_test import libvirt
+            support_machine_type = libvirt.get_machine_types(
+                'aarch64', hvm_or_pv, ignore_status=False)
+            if machine_type not in support_machine_type:
+                logging.warn("Unsupported machine type %s", machine_type)
+                machine_type = 'virt'
             qemu_path = qemu_path + " -M" + " %s" % machine_type
         if (utils_qemu.has_device_category(qemu_path, "CPU")
                 and params.get("cpu_driver") is None):

virttest/qemu_vm.py

@@ -1412,7 +1412,17 @@ class VM(virt_vm.BaseVM):
                                                                  shell=True)).split(',')[0]
         # aarch64 use "qemu-kvm -M machine_type -cpu ?" to get supported cpu models.
         if platform.machine() == 'aarch64':
-            machine_type = params.get("machine_type").split(':', 1)[1]
+            machine_type = params.get("machine_type")
+            if ':' in machine_type:
+                machine_type = machine_type.split(':', 1)[1]
+            # Needed to judge if machine_type supported in arm
+            hvm_or_pv = params.get("hvm_or_pv", "hvm")
+            from virttest.utils_test import libvirt
+            support_machine_type = libvirt.get_machine_types(
+                'aarch64', hvm_or_pv, ignore_status=False)
+            if machine_type not in support_machine_type:
+                logging.warn("Unsupported machine type %s", machine_type)
+                machine_type = 'virt'
             support_cpu_model = decode_to_text(process.system_output("%s -M %s -cpu \\? " % (qemu_binary, machine_type),
                                                                      verbose=False,
                                                                      ignore_status=True,