diff --git a/src/ior.c b/src/ior.c
index 57f385d..5e343d1 100755
--- a/src/ior.c
+++ b/src/ior.c
@@ -1946,6 +1946,13 @@ static IOR_offset_t WriteOrRead(IOR_param_t *test, IOR_results_t *results,
                 hitStonewall = ((test->deadlineForStonewalling != 0
                                 && (GetTimeStamp() - startForStonewall)
                                     > test->deadlineForStonewalling)) || (test->stoneWallingWearOutIterations != 0 && pairCnt == test->stoneWallingWearOutIterations) ;
+
+                if ( test->collective && test->deadlineForStonewalling ) {
+                        // if collective-mode, you'll get a HANG, if some rank 'accidentally' leave this loop
+                        // it absolutely must be an 'all or none':
+                        MPI_CHECK(MPI_Bcast(&hitStonewall, 1, MPI_INT, 0, MPI_COMM_WORLD), "hitStonewall broadcast failed");
+               }
+
         }
         if (test->stoneWallingWearOut){
           if (verbose >= VERBOSE_1){