fix unshielded futures

controller/controller.py

@@ -1119,7 +1119,7 @@ class JobManager(Manager):
                 try:
                     # graceful kill
                     kill(sig)
-                    yield from asyncio.wait_for(wait_task, timeout=5)
+                    yield from asyncio.wait_for(asyncio.shield(wait_task), timeout=5)
                 except asyncio.TimeoutError:
                     # hard kill (after 5 seconds)
                     kill(signal.SIGKILL)

controller/shared_swarm.py

@@ -346,7 +346,7 @@ class _SlaveResourceManager(_ResourceManager):
     @asyncio.coroutine
     def wait_slot(self, name):
         task = self._tasks[name]
-        return (yield from task.__future)
+        return (yield from asyncio.shield(task.__future))
 
     def container_created(self, cid, name):
         pass