avoid traceback when loopback is NoneType

Signed-off-by: Gui Chen <gui.chen@intel.com>

diff --git a/mic/imager/loop.py b/mic/imager/loop.py
index 91b3e9b..27dd677 100644 (file)
--- a/mic/imager/loop.py
+++ b/mic/imager/loop.py
@@ -351,7 +351,10 @@ class LoopImageCreator(BaseImageCreator):
 
     def _unmount_instroot(self):
         for item in reversed(self._instloops):
-            item['loop'].cleanup()
+            try:
+                item['loop'].cleanup()
+            except:
+                pass
 
     def _stage_final_image(self):