[tip: timers/urgent] selftests: timers: Add a test for disarmed SIGEV_NONE timers

[tip-bot2 for Hung-Jui Lin]

The following commit has been merged into the timers/urgent branch of tip:

Commit-ID:     45aeb7b3039355cfaf01ee1f7e104a55a8d61d0b
Gitweb:        https://git.kernel.org/tip/45aeb7b3039355cfaf01ee1f7e104a55a8d61d0b
Author:        Hung-Jui Lin <alex.lin.programmer@xxxxxxxxx>
AuthorDate:    Fri, 23 Oct 2026 23:14:11 +08:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxx>
CommitterDate: Sun, 25 Oct 2026 22:43:19 +01:00

selftests: timers: Add a test for disarmed SIGEV_NONE timers

timer_gettime() must report a zero it_value for a disarmed timer. For
SIGEV_NONE timers, common_timer_get() reported the remaining time of the
previous arming instead.

Add check_sigev_none_disarm(). It arms a SIGEV_NONE oneshot timer, checks
that a remaining time is reported, disarms the timer and checks that
it_value is zero. Run it for CLOCK_MONOTONIC and CLOCK_PROCESS_CPUTIME_ID,
as CPU timers use a separate implementation.

Without the preceding fix, the CLOCK_MONOTONIC case fails.

Signed-off-by: Hung-Jui Lin <alex.lin.programmer@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxx>
Link: https://patch.msgid.link/20261023151411.28685-2-alex.lin.programmer@xxxxxxxxx
---
 tools/testing/selftests/timers/posix_timers.c | 43 +++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/timers/posix_timers.c b/tools/testing/selftests/timers/posix_timers.c
index a92d4b9..1cf6444 100644
--- a/tools/testing/selftests/timers/posix_timers.c
+++ b/tools/testing/selftests/timers/posix_timers.c
@@ -495,6 +495,45 @@ static void check_sigev_none(int which)
 			 "check_sigev_none %s\n", name);
 }
 
+static void check_sigev_none_disarm(int which)
+{
+	const char *name = clock_name(which);
+	struct itimerspec its;
+	struct sigevent sev;
+	timer_t timerid;
+	bool armed;
+
+	memset(&sev, 0, sizeof(sev));
+	sev.sigev_notify = SIGEV_NONE;
+
+	if (timer_create(which, &sev, &timerid))
+		fatal_error(name, "timer_create()");
+
+	/* Start a oneshot timer which does not expire during the test */
+	memset(&its, 0, sizeof(its));
+	its.it_value.tv_sec = 100;
+	if (timer_settime(timerid, 0, &its, NULL))
+		fatal_error(name, "timer_settime()");
+
+	if (timer_gettime(timerid, &its))
+		fatal_error(name, "timer_gettime()");
+	armed = its.it_value.tv_sec || its.it_value.tv_nsec;
+
+	/* Disarm it. The remaining time must be reported as 0 */
+	memset(&its, 0, sizeof(its));
+	if (timer_settime(timerid, 0, &its, NULL))
+		fatal_error(name, "timer_settime()");
+
+	if (timer_gettime(timerid, &its))
+		fatal_error(name, "timer_gettime()");
+
+	if (timer_delete(timerid))
+		fatal_error(name, "timer_delete()");
+
+	ksft_test_result(armed && !its.it_value.tv_sec && !its.it_value.tv_nsec,
+			 "%s %s\n", __func__, name);
+}
+
 static void check_gettime(int which)
 {
 	const char *name = clock_name(which);
@@ -680,7 +719,7 @@ int main(int argc, char **argv)
 
 	ksft_print_header();
 	if (run_sig_ign_tests) {
-		ksft_set_plan(19);
+		ksft_set_plan(21);
 	} else {
 		ksft_set_plan(10);
 	}
@@ -714,6 +753,8 @@ int main(int argc, char **argv)
 		check_delete();
 		check_sigev_none(CLOCK_MONOTONIC);
 		check_sigev_none(CLOCK_PROCESS_CPUTIME_ID);
+		check_sigev_none_disarm(CLOCK_MONOTONIC);
+		check_sigev_none_disarm(CLOCK_PROCESS_CPUTIME_ID);
 		check_gettime(CLOCK_MONOTONIC);
 		check_gettime(CLOCK_PROCESS_CPUTIME_ID);
 		check_gettime(CLOCK_THREAD_CPUTIME_ID);