tests/acceptance/virtio_check_params: Improve exception logging

Message-Id: <20200129212345.20547-18-philmd@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
diff --git a/tests/acceptance/virtio_check_params.py b/tests/acceptance/virtio_check_params.py
index 5458573..270f69d 100755
--- a/tests/acceptance/virtio_check_params.py
+++ b/tests/acceptance/virtio_check_params.py
@@ -77,8 +77,12 @@
             vm.set_machine(mt["name"])
             for s in VM_DEV_PARAMS[dev_type_name]:
                 vm.add_args(s)
-            vm.launch()
-            query_ok, props, error = self.query_virtqueue(vm, dev_type_name)
+            try:
+                vm.launch()
+                query_ok, props, error = self.query_virtqueue(vm, dev_type_name)
+            except:
+                query_ok = False
+                error = sys.exc_info()[0]
 
         if not query_ok:
             self.fail('machine type {0}: {1}'.format(mt['name'], error))