diff --git a/tools/testing/selftests/membarrier/membarrier_test_impl.h b/tools/testing/selftests/membarrier/membarrier_test_impl.h
index 29aac3bc4988..b4dcbb32538d 100644
--- a/tools/testing/selftests/membarrier/membarrier_test_impl.h
+++ b/tools/testing/selftests/membarrier/membarrier_test_impl.h
@@ -113,6 +113,16 @@ static int test_membarrier_private_expedited_fail(void)
 	int cmd = MEMBARRIER_CMD_PRIVATE_EXPEDITED, flags = 0;
 	const char *test_name = "sys membarrier MEMBARRIER_CMD_PRIVATE_EXPEDITED not registered failure";
 
+	/*
+	 * Some C libraries, like Musl, register the private expedited barrier
+	 * command when creating a thread. Expecting an EPERM on an unregistered
+	 * command will therefore no longer work. Skip the test in this case.
+	 */
+	if (MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED & membarrier_get_registrations()) {
+		ksft_test_result_skip("%s test: Command already registered\n", test_name);
+		return 0;
+	}
+
 	if (sys_membarrier(cmd, flags) != -1) {
 		ksft_exit_fail_msg(
 			"%s test: flags = %d. Should fail, but passed\n",