diff --git a/src/sys/util.c b/src/sys/util.c
index 8989b52a..a5b56234 100644
--- a/src/sys/util.c
+++ b/src/sys/util.c
@@ -722,7 +722,7 @@ NTSTATUS FspSafeMdlCreate(PMDL UserMdl, LOCK_OPERATION Operation, FSP_SAFE_MDL *
     ULONG BufferPageCount;
 
     ASSERT(0 != PageCount);
-    ASSERT(FlagOn(UserMdl->MdlFlags, MDL_PAGES_LOCKED));
+    ASSERT(FlagOn(UserMdl->MdlFlags, MDL_SOURCE_IS_NONPAGED_POOL | MDL_PAGES_LOCKED));
 
     *PSafeMdl = 0;