From: Thomas Weißschuh Date: Thu, 13 Jun 2024 15:24:51 +0000 (+0200) Subject: leds: triggers: Flush pending brightness before activating trigger X-Git-Tag: io_uring-6.11-20240722~53^2~40 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=ab477b766edd3bfb6321a6e3df4c790612613fae;p=linux-2.6-block.git leds: triggers: Flush pending brightness before activating trigger 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 Signed-off-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20240613-led-trigger-flush-v2-1-f4f970799d77@weissschuh.net Signed-off-by: Lee Jones --- diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index 59deadb86335..78eb20093b2c 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -201,6 +201,12 @@ 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 b4688d1d9d2b..1d213c999d40 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);