gistfile1.txt

diff --git a/virttest/qemu_vm.py b/virttest/qemu_vm.py
index 64a8221..44aafeb 100644
--- a/virttest/qemu_vm.py
+++ b/virttest/qemu_vm.py
@@ -992,6 +992,8 @@ class VM(virt_vm.BaseVM):
                     spice_opts.append(opt_string % tmp)
                 elif fallback:
                     spice_opts.append(fallback)
+                else:
+                    spice_opts.pop(key, None)
             s_port = str(utils_misc.find_free_port(*port_range))
             if optget("spice_port") == "generate":
                 if not self.is_alive():