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

Commit-ID:     6279abf16a014474fba3de2e28b6ede871141cde
Gitweb:        https://git.kernel.org/tip/6279abf16a014474fba3de2e28b6ede871141cde
Author:        Anna-Maria Behnsen <anna-maria@linutronix.de>
AuthorDate:    Mon, 14 Oct 2024 10:22:26 +02:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Wed, 16 Oct 2024 00:36:47 +02:00

timers: Add a warning to usleep_range_state() for wrong order of arguments

There is a warning in checkpatch script that triggers, when min and max
arguments of usleep_range_state() are in reverse order. This check does
only cover callsites which uses constants. Add this check into the code as
a WARN_ON_ONCE() to also cover callsites not using constants and fix the
mis-usage by resetting the delta to 0.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20241014-devel-anna-maria-b4-timers-flseep-v3-9-dc8b907cb62f@linutronix.de

---
 kernel/time/sleep_timeout.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/time/sleep_timeout.c b/kernel/time/sleep_timeout.c
index f3f246e..3054e52 100644
--- a/kernel/time/sleep_timeout.c
+++ b/kernel/time/sleep_timeout.c
@@ -364,6 +364,9 @@ void __sched usleep_range_state(unsigned long min, unsigned long max, unsigned i
 	ktime_t exp = ktime_add_us(ktime_get(), min);
 	u64 delta = (u64)(max - min) * NSEC_PER_USEC;
 
+	if (WARN_ON_ONCE(max < min))
+		delta = 0;
+
 	for (;;) {
 		__set_current_state(state);
 		/* Do not return before the requested sleep time has elapsed */