Index: /trunk/src/VBox/VMM/PDMAsyncCompletion.cpp
===================================================================
--- /trunk/src/VBox/VMM/PDMAsyncCompletion.cpp	(revision 31182)
+++ /trunk/src/VBox/VMM/PDMAsyncCompletion.cpp	(revision 31183)
@@ -884,5 +884,5 @@
 
     /* Check that the flags are valid. */
-    AssertReturn(((~(PDMACEP_FILE_FLAGS_READ_ONLY | PDMACEP_FILE_FLAGS_CACHING) & fFlags) == 0),
+    AssertReturn(((~(PDMACEP_FILE_FLAGS_READ_ONLY | PDMACEP_FILE_FLAGS_CACHING | PDMACEP_FILE_FLAGS_DONT_LOCK) & fFlags) == 0),
                  VERR_INVALID_PARAMETER);