diff --git a/lib/cmdlib.py b/lib/cmdlib.py
index 73c4e5dff39c634233aa4ce840fd854869f1585e..4d20e103e6861208862ef0adf8d5b444b30ca56b 100644
--- a/lib/cmdlib.py
+++ b/lib/cmdlib.py
@@ -1348,7 +1348,6 @@ class LURepairDiskSizes(NoHooksLU):
         if full_name is None:
           raise errors.OpPrereqError("Instance '%s' not known" % name)
         self.wanted_names.append(full_name)
-      self.needed_locks[locking.LEVEL_INSTANCE] = self.wanted_names
       self.needed_locks = {
         locking.LEVEL_NODE: [],
         locking.LEVEL_INSTANCE: self.wanted_names,