5.15-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Weißschuh linux@weissschuh.net
[ Upstream commit ab477b766edd3bfb6321a6e3df4c790612613fae ]
The race fixed in timer_trig_activate() between a blocking set_brightness() call and trigger->activate() can affect any trigger. So move the call to flush_work() into led_trigger_set() where it can avoid the race for all triggers.
Fixes: 0db37915d912 ("leds: avoid races with workqueue") Fixes: 8c0f693c6eff ("leds: avoid flush_work in atomic context") Cc: stable@vger.kernel.org Tested-by: Dustin L. Howett dustin@howett.net Signed-off-by: Thomas Weißschuh linux@weissschuh.net Link: https://lore.kernel.org/r/20240613-led-trigger-flush-v2-1-f4f970799d77@weiss... Signed-off-by: Lee Jones lee@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/leds/led-triggers.c | 6 ++++++ drivers/leds/trigger/ledtrig-timer.c | 5 ----- 2 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index fe7fb2e7149c5..3d3673c197e38 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -200,6 +200,12 @@ int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig) */ synchronize_rcu();
+ /* + * If "set brightness to 0" is pending in workqueue, + * we don't want that to be reordered after ->activate() + */ + flush_work(&led_cdev->set_brightness_work); + ret = 0; if (trig->activate) ret = trig->activate(led_cdev); diff --git a/drivers/leds/trigger/ledtrig-timer.c b/drivers/leds/trigger/ledtrig-timer.c index b4688d1d9d2b2..1d213c999d40a 100644 --- a/drivers/leds/trigger/ledtrig-timer.c +++ b/drivers/leds/trigger/ledtrig-timer.c @@ -110,11 +110,6 @@ static int timer_trig_activate(struct led_classdev *led_cdev) led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER; }
- /* - * If "set brightness to 0" is pending in workqueue, we don't - * want that to be reordered after blink_set() - */ - flush_work(&led_cdev->set_brightness_work); led_blink_set(led_cdev, &led_cdev->blink_delay_on, &led_cdev->blink_delay_off);