diff --git a/test/testmtx.c b/test/testmtx.c
index 149f47d11..83c6278b1 100644
--- a/test/testmtx.c
+++ b/test/testmtx.c
@@ -399,6 +399,7 @@ static void mtx4_execute(void) {
   test_assert(11, chThdGetPriority() == p2, "wrong priority level");
   chSysLock();
   chMtxUnlockS();
+  chSchRescheduleS();
   chSysUnlock();
   test_assert(12, chThdGetPriority() == p1, "wrong priority level");
   chThdSleepMilliseconds(100);
diff --git a/test/testsem.c b/test/testsem.c
index d4b990797..c97a3d35d 100644
--- a/test/testsem.c
+++ b/test/testsem.c
@@ -102,6 +102,7 @@ static void sem1_execute(void) {
   threads[0] = chThdCreateStatic(wa[0], WA_SIZE, chThdGetPriority()+5, thread1, "A");
   chSysLock();
   chSemAddCounterI(&sem1, 2);
+  chSchRescheduleS();
   chSysUnlock();
   test_wait_threads();
   test_assert(2, chSemGetCounterI(&sem1) == 1, "invalid counter");