Attempt to fix celery/celery#1965

kombu/utils/eventio.py

@@ -202,7 +202,14 @@ class _select(Poller):
                     self.unregister(fd)
 
     def unregister(self, fd):
-        fd = fileno(fd)
+        try:
+            fd = fileno(fd)
+        except socket.error as exc:
+            # we don't know the previous fd of this object
+            # but it will be removed by the next poll iteration.
+            if get_errno(exc) in SELECT_BAD_FD:
+                return
+            raise
         self._rfd.discard(fd)
         self._wfd.discard(fd)
         self._efd.discard(fd)