1 files changed, 2 insertions, 0 deletions
diff --git a/test/testsem.c b/test/testsem.c
index 6a6a622ef..d5c9072a7 100644
--- a/test/testsem.c
+++ b/test/testsem.c
@@ -104,7 +104,9 @@ static void sem1_execute(void) {
   test_assert_sequence(1, "ABCDE");
 #endif
   threads[0] = chThdCreateStatic(wa[0], WA_SIZE, chThdGetPriority()+5, thread1, "A");
+  chSysLock();
   chSemAddCounterI(&sem1, 2);
+  chSysUnlock();
   test_wait_threads();
   test_assert(2, chSemGetCounterI(&sem1) == 1, "invalid counter");
 }