[PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Anders Roxell]

When building kselftests/capabilities the following warning shows up:

clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
        } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test_execve.c:136:9: note: uninitialized use occurs here
        return have_outer_privilege;
               ^~~~~~~~~~~~~~~~~~~~
test_execve.c:121:9: note: remove the 'if' if its condition is always true
        } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
        bool have_outer_privilege;
                                 ^
                                  = false

Rework so all the ksft_exit_*() functions have attribue
'__attribute__((noreturn))' so the compiler knows that there wont be
any return from the function. That said, without
'__attribute__((noreturn))' the compiler warns about the above issue
since it thinks that it will get back from the ksft_exit_skip()
function, which it wont.
Cleaning up the callers that rely on ksft_exit_*() return code, since
the functions ksft_exit_*() have never returned anything.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
---
 tools/testing/selftests/clone3/clone3.c              |  2 +-
 .../testing/selftests/clone3/clone3_clear_sighand.c  |  2 +-
 tools/testing/selftests/clone3/clone3_set_tid.c      |  2 +-
 tools/testing/selftests/ipc/msgque.c                 | 10 +++++-----
 tools/testing/selftests/kcmp/kcmp_test.c             |  2 +-
 tools/testing/selftests/kselftest.h                  | 12 ++++++------
 .../membarrier/membarrier_test_multi_thread.c        |  2 +-
 .../membarrier/membarrier_test_single_thread.c       |  2 +-
 tools/testing/selftests/openat2/openat2_test.c       |  5 +----
 tools/testing/selftests/pidfd/pidfd_fdinfo_test.c    |  2 +-
 tools/testing/selftests/pidfd/pidfd_open_test.c      |  2 +-
 tools/testing/selftests/pidfd/pidfd_poll_test.c      |  2 +-
 tools/testing/selftests/pidfd/pidfd_test.c           |  2 +-
 tools/testing/selftests/resctrl/resctrl_tests.c      |  6 +++---
 tools/testing/selftests/sync/sync_test.c             |  2 +-
 tools/testing/selftests/timers/adjtick.c             |  5 +----
 tools/testing/selftests/timers/alarmtimer-suspend.c  |  4 +---
 tools/testing/selftests/timers/change_skew.c         |  7 +------
 tools/testing/selftests/timers/clocksource-switch.c  |  4 +---
 tools/testing/selftests/timers/freq-step.c           |  5 +----
 tools/testing/selftests/timers/inconsistency-check.c |  4 ++--
 tools/testing/selftests/timers/leap-a-day.c          | 10 +++++-----
 tools/testing/selftests/timers/leapcrash.c           |  4 ++--
 tools/testing/selftests/timers/mqueue-lat.c          |  7 +------
 tools/testing/selftests/timers/nanosleep.c           |  4 ++--
 tools/testing/selftests/timers/nsleep-lat.c          |  4 ++--
 tools/testing/selftests/timers/posix_timers.c        | 12 ++++++------
 tools/testing/selftests/timers/raw_skew.c            |  6 +++---
 tools/testing/selftests/timers/set-2038.c            |  4 ++--
 tools/testing/selftests/timers/set-tai.c             |  4 ++--
 tools/testing/selftests/timers/set-timer-lat.c       |  4 ++--
 tools/testing/selftests/timers/set-tz.c              |  4 ++--
 tools/testing/selftests/timers/skew_consistency.c    |  4 ++--
 tools/testing/selftests/timers/threadtest.c          |  2 +-
 tools/testing/selftests/timers/valid-adjtimex.c      |  6 +++---
 tools/testing/selftests/vm/madv_populate.c           |  2 +-
 36 files changed, 69 insertions(+), 92 deletions(-)

diff --git a/tools/testing/selftests/clone3/clone3.c b/tools/testing/selftests/clone3/clone3.c
index 42be3b925830..1138a8159782 100644
--- a/tools/testing/selftests/clone3/clone3.c
+++ b/tools/testing/selftests/clone3/clone3.c
@@ -191,5 +191,5 @@ int main(int argc, char *argv[])
 	test_clone3(CLONE_NEWPID, getpagesize() + 8, -E2BIG,
 			CLONE3_ARGS_NO_TEST);
 
-	return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
+	ksft_exit(!ksft_get_fail_cnt());
 }
diff --git a/tools/testing/selftests/clone3/clone3_clear_sighand.c b/tools/testing/selftests/clone3/clone3_clear_sighand.c
index 47a8c0fc3676..dcd9448eaeec 100644
--- a/tools/testing/selftests/clone3/clone3_clear_sighand.c
+++ b/tools/testing/selftests/clone3/clone3_clear_sighand.c
@@ -124,5 +124,5 @@ int main(int argc, char **argv)
 
 	test_clone3_clear_sighand();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/clone3/clone3_set_tid.c b/tools/testing/selftests/clone3/clone3_set_tid.c
index 0229e9ebb995..c6f6625acba9 100644
--- a/tools/testing/selftests/clone3/clone3_set_tid.c
+++ b/tools/testing/selftests/clone3/clone3_set_tid.c
@@ -393,5 +393,5 @@ int main(int argc, char *argv[])
 out:
 	ret = 0;
 
-	return !ret ? ksft_exit_pass() : ksft_exit_fail();
+	ksft_exit(!ret);
 }
diff --git a/tools/testing/selftests/ipc/msgque.c b/tools/testing/selftests/ipc/msgque.c
index 656c43c24044..21dd6af76b21 100644
--- a/tools/testing/selftests/ipc/msgque.c
+++ b/tools/testing/selftests/ipc/msgque.c
@@ -198,13 +198,13 @@ int main(int argc, char **argv)
 	struct msgque_data msgque;
 
 	if (getuid() != 0)
-		return ksft_exit_skip(
+		ksft_exit_skip(
 				"Please run the test as root - Exiting.\n");
 
 	msgque.key = ftok(argv[0], 822155650);
 	if (msgque.key == -1) {
 		printf("Can't make key: %d\n", -errno);
-		return ksft_exit_fail();
+		ksft_exit_fail();
 	}
 
 	msgque.msq_id = msgget(msgque.key, IPC_CREAT | IPC_EXCL | 0666);
@@ -243,13 +243,13 @@ int main(int argc, char **argv)
 		printf("Failed to test queue: %d\n", err);
 		goto err_out;
 	}
-	return ksft_exit_pass();
+	ksft_exit_pass();
 
 err_destroy:
 	if (msgctl(msgque.msq_id, IPC_RMID, NULL)) {
 		printf("Failed to destroy queue: %d\n", -errno);
-		return ksft_exit_fail();
+		ksft_exit_fail();
 	}
 err_out:
-	return ksft_exit_fail();
+	ksft_exit_fail();
 }
diff --git a/tools/testing/selftests/kcmp/kcmp_test.c b/tools/testing/selftests/kcmp/kcmp_test.c
index 6ea7b9f37a41..4e0776c044d1 100644
--- a/tools/testing/selftests/kcmp/kcmp_test.c
+++ b/tools/testing/selftests/kcmp/kcmp_test.c
@@ -162,5 +162,5 @@ int main(int argc, char **argv)
 
 	waitpid(pid2, &status, P_ALL);
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index 8d50483fe204..e47f634bf5c0 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -207,13 +207,13 @@ static inline void ksft_test_result_error(const char *msg, ...)
 	va_end(args);
 }
 
-static inline int ksft_exit_pass(void)
+static inline void __attribute__((noreturn)) ksft_exit_pass(void)
 {
 	ksft_print_cnts();
 	exit(KSFT_PASS);
 }
 
-static inline int ksft_exit_fail(void)
+static inline void __attribute__((noreturn)) ksft_exit_fail(void)
 {
 	ksft_print_cnts();
 	exit(KSFT_FAIL);
@@ -231,7 +231,7 @@ static inline int ksft_exit_fail(void)
 		ksft_exit_fail();	\
 	} while (0)
 
-static inline int ksft_exit_fail_msg(const char *msg, ...)
+static inline void __attribute__((noreturn)) ksft_exit_fail_msg(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -246,19 +246,19 @@ static inline int ksft_exit_fail_msg(const char *msg, ...)
 	exit(KSFT_FAIL);
 }
 
-static inline int ksft_exit_xfail(void)
+static inline void __attribute__((noreturn)) ksft_exit_xfail(void)
 {
 	ksft_print_cnts();
 	exit(KSFT_XFAIL);
 }
 
-static inline int ksft_exit_xpass(void)
+static inline void __attribute__((noreturn)) ksft_exit_xpass(void)
 {
 	ksft_print_cnts();
 	exit(KSFT_XPASS);
 }
 
-static inline int ksft_exit_skip(const char *msg, ...)
+static inline void __attribute__((noreturn)) ksft_exit_skip(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
diff --git a/tools/testing/selftests/membarrier/membarrier_test_multi_thread.c b/tools/testing/selftests/membarrier/membarrier_test_multi_thread.c
index ac5613e5b0eb..b055625e4eb5 100644
--- a/tools/testing/selftests/membarrier/membarrier_test_multi_thread.c
+++ b/tools/testing/selftests/membarrier/membarrier_test_multi_thread.c
@@ -69,5 +69,5 @@ int main(int argc, char **argv)
 	/* Multi-threaded */
 	test_mt_membarrier();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/membarrier/membarrier_test_single_thread.c b/tools/testing/selftests/membarrier/membarrier_test_single_thread.c
index c1c963902854..daec48e0b6f2 100644
--- a/tools/testing/selftests/membarrier/membarrier_test_single_thread.c
+++ b/tools/testing/selftests/membarrier/membarrier_test_single_thread.c
@@ -20,5 +20,5 @@ int main(int argc, char **argv)
 
 	test_membarrier_success();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/openat2/openat2_test.c b/tools/testing/selftests/openat2/openat2_test.c
index 1bddbe934204..b33f548bfca9 100644
--- a/tools/testing/selftests/openat2/openat2_test.c
+++ b/tools/testing/selftests/openat2/openat2_test.c
@@ -320,8 +320,5 @@ int main(int argc, char **argv)
 	test_openat2_struct();
 	test_openat2_flags();
 
-	if (ksft_get_fail_cnt() + ksft_get_error_cnt() > 0)
-		ksft_exit_fail();
-	else
-		ksft_exit_pass();
+	ksft_exit(!(ksft_get_fail_cnt() + ksft_get_error_cnt()));
 }
diff --git a/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c b/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
index 22558524f71c..d6c5cfd1c4c6 100644
--- a/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
+++ b/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
@@ -292,5 +292,5 @@ int main(int argc, char **argv)
 	test_pidfd_fdinfo_nspid();
 	test_pidfd_dead_fdinfo();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/pidfd/pidfd_open_test.c b/tools/testing/selftests/pidfd/pidfd_open_test.c
index 8a59438ccc78..7cad4ccfc347 100644
--- a/tools/testing/selftests/pidfd/pidfd_open_test.c
+++ b/tools/testing/selftests/pidfd/pidfd_open_test.c
@@ -159,5 +159,5 @@ int main(int argc, char **argv)
 	if (pidfd >= 0)
 		close(pidfd);
 
-	return !ret ? ksft_exit_pass() : ksft_exit_fail();
+	ksft_exit(!ret);
 }
diff --git a/tools/testing/selftests/pidfd/pidfd_poll_test.c b/tools/testing/selftests/pidfd/pidfd_poll_test.c
index 610811275357..55d74a50358f 100644
--- a/tools/testing/selftests/pidfd/pidfd_poll_test.c
+++ b/tools/testing/selftests/pidfd/pidfd_poll_test.c
@@ -112,5 +112,5 @@ int main(int argc, char **argv)
 	}
 
 	ksft_test_result_pass("pidfd poll test: pass\n");
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/pidfd/pidfd_test.c b/tools/testing/selftests/pidfd/pidfd_test.c
index 529eb700ac26..4a4ab7e25796 100644
--- a/tools/testing/selftests/pidfd/pidfd_test.c
+++ b/tools/testing/selftests/pidfd/pidfd_test.c
@@ -569,5 +569,5 @@ int main(int argc, char **argv)
 	test_pidfd_send_signal_exited_fail();
 	test_pidfd_send_signal_recycled_pid_fail();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
index 973f09a66e1e..e1cf5a73571b 100644
--- a/tools/testing/selftests/resctrl/resctrl_tests.c
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -205,7 +205,7 @@ int main(int argc, char **argv)
 	 * 2. We execute perf commands
 	 */
 	if (geteuid() != 0)
-		return ksft_exit_fail_msg("Not running as root, abort testing.\n");
+		ksft_exit_fail_msg("Not running as root, abort testing.\n");
 
 	/* Detect AMD vendor */
 	detect_amd();
@@ -235,7 +235,7 @@ int main(int argc, char **argv)
 	sprintf(bm_type, "fill_buf");
 
 	if (!check_resctrlfs_support())
-		return ksft_exit_fail_msg("resctrl FS does not exist\n");
+		ksft_exit_fail_msg("resctrl FS does not exist\n");
 
 	filter_dmesg();
 
@@ -255,5 +255,5 @@ int main(int argc, char **argv)
 
 	umount_resctrlfs();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/sync/sync_test.c b/tools/testing/selftests/sync/sync_test.c
index 414a617db993..aec7057696de 100644
--- a/tools/testing/selftests/sync/sync_test.c
+++ b/tools/testing/selftests/sync/sync_test.c
@@ -110,5 +110,5 @@ int main(void)
 					err, ksft_test_num());
 
 	/* need this return to keep gcc happy */
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/adjtick.c b/tools/testing/selftests/timers/adjtick.c
index 54d8d87f36b3..c917129f142f 100644
--- a/tools/testing/selftests/timers/adjtick.c
+++ b/tools/testing/selftests/timers/adjtick.c
@@ -204,8 +204,5 @@ int main(int argv, char **argc)
 
 	adjtimex(&tx1);
 
-	if (err)
-		return ksft_exit_fail();
-
-	return ksft_exit_pass();
+	ksft_exit(!err);
 }
diff --git a/tools/testing/selftests/timers/alarmtimer-suspend.c b/tools/testing/selftests/timers/alarmtimer-suspend.c
index 4da09dbf83ba..c7c175f3f918 100644
--- a/tools/testing/selftests/timers/alarmtimer-suspend.c
+++ b/tools/testing/selftests/timers/alarmtimer-suspend.c
@@ -172,7 +172,5 @@ int main(void)
 		}
 		timer_delete(tm1);
 	}
-	if (final_ret)
-		return ksft_exit_fail();
-	return ksft_exit_pass();
+	ksft_exit(!final_ret);
 }
diff --git a/tools/testing/selftests/timers/change_skew.c b/tools/testing/selftests/timers/change_skew.c
index c4eab7124990..afd65745e7c2 100644
--- a/tools/testing/selftests/timers/change_skew.c
+++ b/tools/testing/selftests/timers/change_skew.c
@@ -87,10 +87,5 @@ int main(int argv, char **argc)
 	tx.offset = 0;
 	adjtimex(&tx);
 
-	if (ret) {
-		printf("[FAIL]");
-		return ksft_exit_fail();
-	}
-	printf("[OK]");
-	return ksft_exit_pass();
+	ksft_exit(!ret);
 }
diff --git a/tools/testing/selftests/timers/clocksource-switch.c b/tools/testing/selftests/timers/clocksource-switch.c
index ef8eb3604595..41bce2ed8ef4 100644
--- a/tools/testing/selftests/timers/clocksource-switch.c
+++ b/tools/testing/selftests/timers/clocksource-switch.c
@@ -162,7 +162,5 @@ int main(int argv, char **argc)
 out:
 	change_clocksource(orig_clk);
 
-	if (status)
-		return ksft_exit_fail();
-	return ksft_exit_pass();
+	ksft_exit(!status);
 }
diff --git a/tools/testing/selftests/timers/freq-step.c b/tools/testing/selftests/timers/freq-step.c
index 4b76450d78d1..f060fa5450d1 100644
--- a/tools/testing/selftests/timers/freq-step.c
+++ b/tools/testing/selftests/timers/freq-step.c
@@ -256,8 +256,5 @@ int main(int argc, char **argv)
 
 	set_frequency(0.0);
 
-	if (fails)
-		return ksft_exit_fail();
-
-	return ksft_exit_pass();
+	ksft_exit(!fails);
 }
diff --git a/tools/testing/selftests/timers/inconsistency-check.c b/tools/testing/selftests/timers/inconsistency-check.c
index 022d3ffe3fbf..71362be52dc8 100644
--- a/tools/testing/selftests/timers/inconsistency-check.c
+++ b/tools/testing/selftests/timers/inconsistency-check.c
@@ -186,8 +186,8 @@ int main(int argc, char *argv[])
 		if (!clock_gettime(clockid, &ts)) {
 			printf("Consistent %-30s ", clockstring(clockid));
 			if (consistency_test(clockid, runtime))
-				return ksft_exit_fail();
+				ksft_exit_fail();
 		}
 	}
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/leap-a-day.c b/tools/testing/selftests/timers/leap-a-day.c
index 23eb398c8140..986abbdb1521 100644
--- a/tools/testing/selftests/timers/leap-a-day.c
+++ b/tools/testing/selftests/timers/leap-a-day.c
@@ -268,7 +268,7 @@ int main(int argc, char **argv)
 		if (ret < 0) {
 			printf("Error: Problem setting STA_INS/STA_DEL!: %s\n",
 							time_state_str(ret));
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 
 		/* Validate STA_INS was set */
@@ -277,7 +277,7 @@ int main(int argc, char **argv)
 		if (tx.status != STA_INS && tx.status != STA_DEL) {
 			printf("Error: STA_INS/STA_DEL not set!: %s\n",
 							time_state_str(ret));
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 
 		if (tai_time) {
@@ -295,7 +295,7 @@ int main(int argc, char **argv)
 		se.sigev_value.sival_int = 0;
 		if (timer_create(CLOCK_REALTIME, &se, &tm1) == -1) {
 			printf("Error: timer_create failed\n");
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 		its1.it_value.tv_sec = next_leap;
 		its1.it_value.tv_nsec = 0;
@@ -366,7 +366,7 @@ int main(int argc, char **argv)
 		if (error_found) {
 			printf("Errors observed\n");
 			clear_time_state();
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 		printf("\n");
 		if ((iterations != -1) && !(--iterations))
@@ -374,5 +374,5 @@ int main(int argc, char **argv)
 	}
 
 	clear_time_state();
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/leapcrash.c b/tools/testing/selftests/timers/leapcrash.c
index f70802c5dd0d..8fd065eec904 100644
--- a/tools/testing/selftests/timers/leapcrash.c
+++ b/tools/testing/selftests/timers/leapcrash.c
@@ -87,7 +87,7 @@ int main(void)
 		tv.tv_usec = 0;
 		if (settimeofday(&tv, NULL)) {
 			printf("Error: You're likely not running with proper (ie: root) permissions\n");
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 		tx.modes = 0;
 		adjtimex(&tx);
@@ -104,5 +104,5 @@ int main(void)
 		fflush(stdout);
 	}
 	printf("[OK]\n");
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/mqueue-lat.c b/tools/testing/selftests/timers/mqueue-lat.c
index 7916cf5cc6ff..66feb333ff98 100644
--- a/tools/testing/selftests/timers/mqueue-lat.c
+++ b/tools/testing/selftests/timers/mqueue-lat.c
@@ -105,10 +105,5 @@ int main(int argc, char **argv)
 	fflush(stdout);
 
 	ret = mqueue_lat_test();
-	if (ret < 0) {
-		printf("[FAILED]\n");
-		return ksft_exit_fail();
-	}
-	printf("[OK]\n");
-	return ksft_exit_pass();
+	ksft_exit(!ret);
 }
diff --git a/tools/testing/selftests/timers/nanosleep.c b/tools/testing/selftests/timers/nanosleep.c
index 71b5441c2fd9..40ff3d710d66 100644
--- a/tools/testing/selftests/timers/nanosleep.c
+++ b/tools/testing/selftests/timers/nanosleep.c
@@ -153,7 +153,7 @@ int main(int argc, char **argv)
 			}
 			if (ret < 0) {
 				printf("[FAILED]\n");
-				return ksft_exit_fail();
+				ksft_exit_fail();
 			}
 			length *= 100;
 		}
@@ -161,5 +161,5 @@ int main(int argc, char **argv)
 next:
 		ret = 0;
 	}
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/nsleep-lat.c b/tools/testing/selftests/timers/nsleep-lat.c
index eb3e79ed7b4a..4c201a06cb94 100644
--- a/tools/testing/selftests/timers/nsleep-lat.c
+++ b/tools/testing/selftests/timers/nsleep-lat.c
@@ -172,9 +172,9 @@ int main(int argc, char **argv)
 		}
 		if (ret < 0) {
 			printf("[FAILED]\n");
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 		printf("[OK]\n");
 	}
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/posix_timers.c b/tools/testing/selftests/timers/posix_timers.c
index 0ba500056e63..337424c5c987 100644
--- a/tools/testing/selftests/timers/posix_timers.c
+++ b/tools/testing/selftests/timers/posix_timers.c
@@ -194,16 +194,16 @@ int main(int argc, char **argv)
 	printf("based timers if other threads run on the CPU...\n");
 
 	if (check_itimer(ITIMER_VIRTUAL) < 0)
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
 	if (check_itimer(ITIMER_PROF) < 0)
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
 	if (check_itimer(ITIMER_REAL) < 0)
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
 	if (check_timer_create(CLOCK_THREAD_CPUTIME_ID) < 0)
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
 	/*
 	 * It's unfortunately hard to reliably test a timer expiration
@@ -215,7 +215,7 @@ int main(int argc, char **argv)
 	 * find a better solution.
 	 */
 	if (check_timer_create(CLOCK_PROCESS_CPUTIME_ID) < 0)
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/raw_skew.c b/tools/testing/selftests/timers/raw_skew.c
index b41d8dd0c40c..b58639a7d19d 100644
--- a/tools/testing/selftests/timers/raw_skew.c
+++ b/tools/testing/selftests/timers/raw_skew.c
@@ -138,11 +138,11 @@ int main(int argv, char **argc)
 		if (tx1.offset || tx2.offset ||
 		    tx1.freq != tx2.freq || tx1.tick != tx2.tick) {
 			printf("	[SKIP]\n");
-			return ksft_exit_skip("The clock was adjusted externally. Shutdown NTPd or other time sync daemons\n");
+			ksft_exit_skip("The clock was adjusted externally. Shutdown NTPd or other time sync daemons\n");
 		}
 		printf("	[FAILED]\n");
-		return ksft_exit_fail();
+		ksft_exit_fail();
 	}
 	printf("	[OK]\n");
-	return  ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/set-2038.c b/tools/testing/selftests/timers/set-2038.c
index 688cfd81b531..f7d978721b9e 100644
--- a/tools/testing/selftests/timers/set-2038.c
+++ b/tools/testing/selftests/timers/set-2038.c
@@ -128,6 +128,6 @@ int main(int argc, char *argv[])
 	/* restore clock */
 	settime(start);
 	if (ret)
-		return ksft_exit_fail();
-	return ksft_exit_pass();
+		ksft_exit_fail();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/set-tai.c b/tools/testing/selftests/timers/set-tai.c
index 8c4179ee2ca2..5b67462efcd6 100644
--- a/tools/testing/selftests/timers/set-tai.c
+++ b/tools/testing/selftests/timers/set-tai.c
@@ -61,9 +61,9 @@ int main(int argc, char **argv)
 		ret = get_tai();
 		if (ret != i) {
 			printf("[FAILED] expected: %i got %i\n", i, ret);
-			return ksft_exit_fail();
+			ksft_exit_fail();
 		}
 	}
 	printf("[OK]\n");
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/set-timer-lat.c b/tools/testing/selftests/timers/set-timer-lat.c
index 50da45437daa..7ce240c89b21 100644
--- a/tools/testing/selftests/timers/set-timer-lat.c
+++ b/tools/testing/selftests/timers/set-timer-lat.c
@@ -278,6 +278,6 @@ int main(void)
 		ret |= do_timer_oneshot(clock_id, 0);
 	}
 	if (ret)
-		return ksft_exit_fail();
-	return ksft_exit_pass();
+		ksft_exit_fail();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/set-tz.c b/tools/testing/selftests/timers/set-tz.c
index 62bd33eb16f0..20daaf1782b7 100644
--- a/tools/testing/selftests/timers/set-tz.c
+++ b/tools/testing/selftests/timers/set-tz.c
@@ -102,9 +102,9 @@ int main(int argc, char **argv)
 	printf("[OK]\n");
 
 	set_tz(min, dst);
-	return ksft_exit_pass();
+	ksft_exit_pass();
 
 err:
 	set_tz(min, dst);
-	return ksft_exit_fail();
+	ksft_exit_fail();
 }
diff --git a/tools/testing/selftests/timers/skew_consistency.c b/tools/testing/selftests/timers/skew_consistency.c
index 8066be9aff11..bfeaac8d870d 100644
--- a/tools/testing/selftests/timers/skew_consistency.c
+++ b/tools/testing/selftests/timers/skew_consistency.c
@@ -70,8 +70,8 @@ int main(int argv, char **argc)
 
 	if (ret) {
 		printf("[FAILED]\n");
-		return ksft_exit_fail();
+		ksft_exit_fail();
 	}
 	printf("[OK]\n");
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/threadtest.c b/tools/testing/selftests/timers/threadtest.c
index 80aed4bf06fb..76b38e41d9c7 100644
--- a/tools/testing/selftests/timers/threadtest.c
+++ b/tools/testing/selftests/timers/threadtest.c
@@ -189,5 +189,5 @@ int main(int argc, char **argv)
 	/* die */
 	if (ret)
 		ksft_exit_fail();
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/timers/valid-adjtimex.c b/tools/testing/selftests/timers/valid-adjtimex.c
index 5397de708d3c..48804223eb4d 100644
--- a/tools/testing/selftests/timers/valid-adjtimex.c
+++ b/tools/testing/selftests/timers/valid-adjtimex.c
@@ -321,10 +321,10 @@ int validate_set_offset(void)
 int main(int argc, char **argv)
 {
 	if (validate_freq())
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
 	if (validate_set_offset())
-		return ksft_exit_fail();
+		ksft_exit_fail();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
diff --git a/tools/testing/selftests/vm/madv_populate.c b/tools/testing/selftests/vm/madv_populate.c
index 3ee0e8275600..5f2f8ad32248 100644
--- a/tools/testing/selftests/vm/madv_populate.c
+++ b/tools/testing/selftests/vm/madv_populate.c
@@ -325,5 +325,5 @@ int main(int argc, char **argv)
 	if (err)
 		ksft_exit_fail_msg("%d out of %d tests failed\n",
 				   err, ksft_test_num());
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }
-- 
2.33.0

Re: [PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Shuah Khan]

On 10/29/21 5:43 AM, Anders Roxell wrote:
> When building kselftests/capabilities the following warning shows up:
> 
> clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
> test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
>          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
>                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> test_execve.c:136:9: note: uninitialized use occurs here
>          return have_outer_privilege;
>                 ^~~~~~~~~~~~~~~~~~~~
> test_execve.c:121:9: note: remove the 'if' if its condition is always true
>          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
>          bool have_outer_privilege;
>                                   ^
>                                    = false
> 
> Rework so all the ksft_exit_*() functions have attribue
> '__attribute__((noreturn))' so the compiler knows that there wont be
> any return from the function. That said, without
> '__attribute__((noreturn))' the compiler warns about the above issue
> since it thinks that it will get back from the ksft_exit_skip()
> function, which it wont.
> Cleaning up the callers that rely on ksft_exit_*() return code, since
> the functions ksft_exit_*() have never returned anything.
> 
> Signed-off-by: Anders Roxell <anders.roxell@linaro.org>

Lot of changes to fix this warning. Is this necessary? I would
like to explore if there is an easier and localized change that
can fix the problem.

thanks,
-- Shuah

Re: [PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Nick Desaulniers]

On Fri, Oct 29, 2021 at 11:19 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
>
> On 10/29/21 5:43 AM, Anders Roxell wrote:
> > When building kselftests/capabilities the following warning shows up:
> >
> > clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
> > test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
> >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> >                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > test_execve.c:136:9: note: uninitialized use occurs here
> >          return have_outer_privilege;
> >                 ^~~~~~~~~~~~~~~~~~~~
> > test_execve.c:121:9: note: remove the 'if' if its condition is always true
> >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
> >          bool have_outer_privilege;
> >                                   ^
> >                                    = false
> >
> > Rework so all the ksft_exit_*() functions have attribue
> > '__attribute__((noreturn))' so the compiler knows that there wont be
> > any return from the function. That said, without
> > '__attribute__((noreturn))' the compiler warns about the above issue
> > since it thinks that it will get back from the ksft_exit_skip()
> > function, which it wont.
> > Cleaning up the callers that rely on ksft_exit_*() return code, since
> > the functions ksft_exit_*() have never returned anything.
> >
> > Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
>
> Lot of changes to fix this warning. Is this necessary? I would
> like to explore if there is an easier and localized change that
> can fix the problem.

via `man 3 exit`:
```
The  exit() function causes normal process termination ...
...
RETURN VALUE
       The exit() function does not return.
```
so seeing `ksft_exit_pass`, `ksft_exit_fail`, `ksft_exit_fail_msg`,
`ksft_exit_xfail`, `ksft_exit_xpass`, and `ksft_exit_skip` all
unconditional call `exit` yet return an `int` looks wrong to me on
first glance. So on that point this patch and its resulting diffstat
LGTM.

That said, there are many changes that explicitly call `ksft_exit`
with an expression; are those setting the correct exit code? Note that
ksft_exit_pass is calling exit with KSFT_PASS which is 0.  So some of
the negations don't look quite correct to me.  For example:

-       return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
+       ksft_exit(!ksft_get_fail_cnt());

so if ksft_get_fail_cnt() returns 0, then we were calling
ksft_exit_pass() which exited with 0. Now we'd be exiting with 1?
-- 
Thanks,
~Nick Desaulniers

Re: [PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Shuah Khan]

On 10/29/21 4:08 PM, Nick Desaulniers wrote:
> On Fri, Oct 29, 2021 at 11:19 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
>>
>> On 10/29/21 5:43 AM, Anders Roxell wrote:
>>> When building kselftests/capabilities the following warning shows up:
>>>
>>> clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
>>> test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
>>>           } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
>>>                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> test_execve.c:136:9: note: uninitialized use occurs here
>>>           return have_outer_privilege;
>>>                  ^~~~~~~~~~~~~~~~~~~~
>>> test_execve.c:121:9: note: remove the 'if' if its condition is always true
>>>           } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
>>>                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
>>>           bool have_outer_privilege;
>>>                                    ^
>>>                                     = false
>>>
>>> Rework so all the ksft_exit_*() functions have attribue
>>> '__attribute__((noreturn))' so the compiler knows that there wont be
>>> any return from the function. That said, without
>>> '__attribute__((noreturn))' the compiler warns about the above issue
>>> since it thinks that it will get back from the ksft_exit_skip()
>>> function, which it wont.
>>> Cleaning up the callers that rely on ksft_exit_*() return code, since
>>> the functions ksft_exit_*() have never returned anything.
>>>
>>> Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
>>
>> Lot of changes to fix this warning. Is this necessary? I would
>> like to explore if there is an easier and localized change that
>> can fix the problem.
> 
> via `man 3 exit`:
> ```
> The  exit() function causes normal process termination ...
> ...
> RETURN VALUE
>         The exit() function does not return.
> ```
> so seeing `ksft_exit_pass`, `ksft_exit_fail`, `ksft_exit_fail_msg`,
> `ksft_exit_xfail`, `ksft_exit_xpass`, and `ksft_exit_skip` all
> unconditional call `exit` yet return an `int` looks wrong to me on
> first glance. So on that point this patch and its resulting diffstat
> LGTM.
> 
> That said, there are many changes that explicitly call `ksft_exit`
> with an expression; are those setting the correct exit code? Note that
> ksft_exit_pass is calling exit with KSFT_PASS which is 0.  So some of
> the negations don't look quite correct to me.  For example:
> 
> -       return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
> +       ksft_exit(!ksft_get_fail_cnt());
> 
> so if ksft_get_fail_cnt() returns 0, then we were calling
> ksft_exit_pass() which exited with 0. Now we'd be exiting with 1?
> 

Right. This is another concern I have that the tests will return
a different values and the wrapper will interpret them as failures.

So his doesn't look like the right change to fix the problem.

thanks,
-- Shuah

Re: [PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Anders Roxell]

On Sat, 30 Oct 2021 at 00:08, Nick Desaulniers <ndesaulniers@google.com> wrote:
>
> On Fri, Oct 29, 2021 at 11:19 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
> >
> > On 10/29/21 5:43 AM, Anders Roxell wrote:
> > > When building kselftests/capabilities the following warning shows up:
> > >
> > > clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
> > > test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
> > >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> > >                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > test_execve.c:136:9: note: uninitialized use occurs here
> > >          return have_outer_privilege;
> > >                 ^~~~~~~~~~~~~~~~~~~~
> > > test_execve.c:121:9: note: remove the 'if' if its condition is always true
> > >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> > >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
> > >          bool have_outer_privilege;
> > >                                   ^
> > >                                    = false
> > >
> > > Rework so all the ksft_exit_*() functions have attribue
> > > '__attribute__((noreturn))' so the compiler knows that there wont be
> > > any return from the function. That said, without
> > > '__attribute__((noreturn))' the compiler warns about the above issue
> > > since it thinks that it will get back from the ksft_exit_skip()
> > > function, which it wont.
> > > Cleaning up the callers that rely on ksft_exit_*() return code, since
> > > the functions ksft_exit_*() have never returned anything.
> > >
> > > Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
> >
> > Lot of changes to fix this warning. Is this necessary? I would
> > like to explore if there is an easier and localized change that
> > can fix the problem.
>
> via `man 3 exit`:
> ```
> The  exit() function causes normal process termination ...
> ...
> RETURN VALUE
>        The exit() function does not return.
> ```
> so seeing `ksft_exit_pass`, `ksft_exit_fail`, `ksft_exit_fail_msg`,
> `ksft_exit_xfail`, `ksft_exit_xpass`, and `ksft_exit_skip` all
> unconditional call `exit` yet return an `int` looks wrong to me on
> first glance. So on that point this patch and its resulting diffstat
> LGTM.

I'll respin the patch with these changes only.

>
> That said, there are many changes that explicitly call `ksft_exit`
> with an expression; are those setting the correct exit code? Note that
> ksft_exit_pass is calling exit with KSFT_PASS which is 0.  So some of
> the negations don't look quite correct to me.  For example:
>
> -       return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
> +       ksft_exit(!ksft_get_fail_cnt());
>
> so if ksft_get_fail_cnt() returns 0, then we were calling
> ksft_exit_pass() which exited with 0. Now we'd be exiting with 1?

oh, right, thank you for your review.
I will drop all the 'ksft_exit()' changes, they should be fixed and go
in as separete patches.


Cheers,
Anders

Re: [PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Anders Roxell]

On Tue, 2 Nov 2021 at 23:04, Anders Roxell <anders.roxell@linaro.org> wrote:
>
> On Sat, 30 Oct 2021 at 00:08, Nick Desaulniers <ndesaulniers@google.com> wrote:
> >
> > On Fri, Oct 29, 2021 at 11:19 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
> > >
> > > On 10/29/21 5:43 AM, Anders Roxell wrote:
> > > > When building kselftests/capabilities the following warning shows up:
> > > >
> > > > clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
> > > > test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
> > > >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> > > >                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > > test_execve.c:136:9: note: uninitialized use occurs here
> > > >          return have_outer_privilege;
> > > >                 ^~~~~~~~~~~~~~~~~~~~
> > > > test_execve.c:121:9: note: remove the 'if' if its condition is always true
> > > >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> > > >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > > test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
> > > >          bool have_outer_privilege;
> > > >                                   ^
> > > >                                    = false
> > > >
> > > > Rework so all the ksft_exit_*() functions have attribue
> > > > '__attribute__((noreturn))' so the compiler knows that there wont be
> > > > any return from the function. That said, without
> > > > '__attribute__((noreturn))' the compiler warns about the above issue
> > > > since it thinks that it will get back from the ksft_exit_skip()
> > > > function, which it wont.
> > > > Cleaning up the callers that rely on ksft_exit_*() return code, since
> > > > the functions ksft_exit_*() have never returned anything.
> > > >
> > > > Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
> > >
> > > Lot of changes to fix this warning. Is this necessary? I would
> > > like to explore if there is an easier and localized change that
> > > can fix the problem.
> >
> > via `man 3 exit`:
> > ```
> > The  exit() function causes normal process termination ...
> > ...
> > RETURN VALUE
> >        The exit() function does not return.
> > ```
> > so seeing `ksft_exit_pass`, `ksft_exit_fail`, `ksft_exit_fail_msg`,
> > `ksft_exit_xfail`, `ksft_exit_xpass`, and `ksft_exit_skip` all
> > unconditional call `exit` yet return an `int` looks wrong to me on
> > first glance. So on that point this patch and its resulting diffstat
> > LGTM.
>
> I'll respin the patch with these changes only.
>
> >
> > That said, there are many changes that explicitly call `ksft_exit`
> > with an expression; are those setting the correct exit code? Note that
> > ksft_exit_pass is calling exit with KSFT_PASS which is 0.  So some of
> > the negations don't look quite correct to me.  For example:
> >
> > -       return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
> > +       ksft_exit(!ksft_get_fail_cnt());
> >
> > so if ksft_get_fail_cnt() returns 0, then we were calling
> > ksft_exit_pass() which exited with 0. Now we'd be exiting with 1?
>
> oh, right, thank you for your review.
> I will drop all the 'ksft_exit()' changes, they should be fixed and go
> in as separete patches.

tools/testing/selftests/vm/memfd_secret.c has the
'ksft_exit(!ksft_get_fail_cnt())'
statement and when I looked at it it when I did this patch it looked correct.
However, when I look at it now I get a bit confused how ksft_exit() can be used
with ksft_get_fail_cnt(). @Mike can you please clarify the
'ksft_exit(!ksft_get_fail_cnt())' instance in
tools/testing/selftests/vm/memfd_secret.c.

Cheers,
Anders

Re: [PATCH] selftests: kselftest.h: mark functions with 'noreturn'

[Mike Rapoport]

On Wed, Nov 03, 2021 at 10:38:17AM +0100, Anders Roxell wrote:
> On Tue, 2 Nov 2021 at 23:04, Anders Roxell <anders.roxell@linaro.org> wrote:
> >
> > On Sat, 30 Oct 2021 at 00:08, Nick Desaulniers <ndesaulniers@google.com> wrote:
> > >
> > > On Fri, Oct 29, 2021 at 11:19 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
> > > >
> > > > On 10/29/21 5:43 AM, Anders Roxell wrote:
> > > > > When building kselftests/capabilities the following warning shows up:
> > > > >
> > > > > clang -O2 -g -std=gnu99 -Wall    test_execve.c -lcap-ng -lrt -ldl -o test_execve
> > > > > test_execve.c:121:13: warning: variable 'have_outer_privilege' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
> > > > >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> > > > >                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > > > test_execve.c:136:9: note: uninitialized use occurs here
> > > > >          return have_outer_privilege;
> > > > >                 ^~~~~~~~~~~~~~~~~~~~
> > > > > test_execve.c:121:9: note: remove the 'if' if its condition is always true
> > > > >          } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
> > > > >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > > > test_execve.c:94:27: note: initialize the variable 'have_outer_privilege' to silence this warning
> > > > >          bool have_outer_privilege;
> > > > >                                   ^
> > > > >                                    = false
> > > > >
> > > > > Rework so all the ksft_exit_*() functions have attribue
> > > > > '__attribute__((noreturn))' so the compiler knows that there wont be
> > > > > any return from the function. That said, without
> > > > > '__attribute__((noreturn))' the compiler warns about the above issue
> > > > > since it thinks that it will get back from the ksft_exit_skip()
> > > > > function, which it wont.
> > > > > Cleaning up the callers that rely on ksft_exit_*() return code, since
> > > > > the functions ksft_exit_*() have never returned anything.
> > > > >
> > > > > Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
> > > >
> > > > Lot of changes to fix this warning. Is this necessary? I would
> > > > like to explore if there is an easier and localized change that
> > > > can fix the problem.
> > >
> > > via `man 3 exit`:
> > > ```
> > > The  exit() function causes normal process termination ...
> > > ...
> > > RETURN VALUE
> > >        The exit() function does not return.
> > > ```
> > > so seeing `ksft_exit_pass`, `ksft_exit_fail`, `ksft_exit_fail_msg`,
> > > `ksft_exit_xfail`, `ksft_exit_xpass`, and `ksft_exit_skip` all
> > > unconditional call `exit` yet return an `int` looks wrong to me on
> > > first glance. So on that point this patch and its resulting diffstat
> > > LGTM.
> >
> > I'll respin the patch with these changes only.
> >
> > >
> > > That said, there are many changes that explicitly call `ksft_exit`
> > > with an expression; are those setting the correct exit code? Note that
> > > ksft_exit_pass is calling exit with KSFT_PASS which is 0.  So some of
> > > the negations don't look quite correct to me.  For example:
> > >
> > > -       return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
> > > +       ksft_exit(!ksft_get_fail_cnt());
> > >
> > > so if ksft_get_fail_cnt() returns 0, then we were calling
> > > ksft_exit_pass() which exited with 0. Now we'd be exiting with 1?
> >
> > oh, right, thank you for your review.
> > I will drop all the 'ksft_exit()' changes, they should be fixed and go
> > in as separete patches.
> 
> tools/testing/selftests/vm/memfd_secret.c has the
> 'ksft_exit(!ksft_get_fail_cnt())'
> statement and when I looked at it it when I did this patch it looked correct.
> However, when I look at it now I get a bit confused how ksft_exit() can be used
> with ksft_get_fail_cnt(). @Mike can you please clarify the
> 'ksft_exit(!ksft_get_fail_cnt())' instance in
> tools/testing/selftests/vm/memfd_secret.c.

ksft_exit() does not take the error code but rather a condition:

/**
 * ksft_exit() - Exit selftest based on truth of condition
 *
 * @condition: if true, exit self test with success, otherwise fail.
 */
#define ksft_exit(condition) do {	\
	if (!!(condition))		\
		ksft_exit_pass();	\
	else				\
		ksft_exit_fail();	\
	} while (0)

So

	!ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();

and

	ksft_exit(!ksft_get_fail_cnt())

are equivalent.

-- 
Sincerely yours,
Mike.