From: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> commit ab477b766edd3bfb6321a6e3df4c790612613fae upstream. 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@xxxxxxxxxxxxxxx Tested-by: Dustin L. Howett <dustin@xxxxxxxxxx> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240613-led-trigger-flush-v2-1-f4f970799d77@xxxxxxxxxxxxxx Signed-off-by: Lee Jones <lee@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/leds/led-triggers.c | 6 ++++++ drivers/leds/trigger/ledtrig-timer.c | 5 ----- 2 files changed, 6 insertions(+), 5 deletions(-) --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -194,6 +194,12 @@ int led_trigger_set(struct led_classdev spin_unlock(&trig->leddev_list_lock); led_cdev->trigger = trig; + /* + * 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); --- a/drivers/leds/trigger/ledtrig-timer.c +++ b/drivers/leds/trigger/ledtrig-timer.c @@ -110,11 +110,6 @@ static int timer_trig_activate(struct le 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); Patches currently in stable-queue which might be from linux@xxxxxxxxxxxxxx are queue-6.10/leds-triggers-flush-pending-brightness-before-activating-trigger.patch queue-6.10/selftests-nolibc-fix-printf-format-mismatch-in-expect_str_buf_eq.patch queue-6.10/sysctl-always-initialize-i_uid-i_gid.patch queue-6.10/eeprom-ee1004-call-i2c_new_scanned_device-to-instant.patch