loggers expect exc_info to be falsey or a tuple, pass in the tuple from ExceptionInfo

celery/worker/job.py

@@ -355,7 +355,7 @@ class Request(object):
         if _does_info:
             info(self.retry_msg.strip(), {
                 "id": self.id, "name": self.name,
-                "exc": safe_repr(exc_info.exception.exc)}, exc_info=exc_info)
+                "exc": safe_repr(exc_info.exception.exc)}, exc_info=exc_info.exc_info)
 
     def on_failure(self, exc_info):
         """Handler called if the task raised an exception."""