Does anyone know why this will hang unity editor -- serilize property loop.

     m_selectedIndex = GUILayout.SelectionGrid(m_selectedIndex,m_spawner.getRoundsAsString(),4);

     SpawnerRound sr = m_spawner.getSpawnerRound(m_selectedIndex);

     int n = 0;
     GUILayout.SelectionGrid(n,sr.getEnemies(),1);

     SerializedObject so = new SerializedObject(sr.gameObject);
     //EditorGUILayout.BeginVertical();
     SerializedProperty m_Property = so.GetIterator();
     do {
         Debug.Log("m_property" + m_Property.propertyPath);

         EditorGUILayout.PropertyField(m_Property);
     } while (m_Property.Next(true));