From: Hongyan Xu Date: Wed, 29 Jul 2026 10:01:16 +0000 (+0800) Subject: hwmon: (npcm750-pwm-fan): stop fan timer on device detach X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f27f6976ea269219c1259a7c2f8c6dfe782540a3;p=thirdparty%2Flinux.git hwmon: (npcm750-pwm-fan): stop fan timer on device detach When a fan tach channel is present, npcm7xx_pwm_fan_probe() starts fan_timer. The timer callback polls tach state and rearms the timer, but the driver has no remove callback or devm cleanup action to stop it. On device detach, the devm-managed driver data and I/O mappings can be released while the timer is still pending or running. Register a devm cleanup action before starting the timer and shut the timer down synchronously from that action. This issue was found by a static analysis tool. Fixes: f1fd4a4db777 ("hwmon: Add NPCM7xx PWM and Fan driver") Cc: stable@vger.kernel.org Signed-off-by: Hongyan Xu Link: https://lore.kernel.org/r/20260729100116.790-1-getshell@seu.edu.cn Signed-off-by: Guenter Roeck --- diff --git a/drivers/hwmon/npcm750-pwm-fan.c b/drivers/hwmon/npcm750-pwm-fan.c index aea0b8659f5f..6ff2a6bc06c1 100644 --- a/drivers/hwmon/npcm750-pwm-fan.c +++ b/drivers/hwmon/npcm750-pwm-fan.c @@ -358,6 +358,11 @@ static void npcm7xx_fan_polling(struct timer_list *t) add_timer(&data->fan_timer); } +static void npcm7xx_fan_cleanup(void *timer) +{ + timer_shutdown_sync(timer); +} + static inline void npcm7xx_fan_compute(struct npcm7xx_pwm_fan_data *data, u8 fan, u8 cmp, u8 fan_id, u8 flag_int, u8 flag_mode, u8 flag_clear) @@ -1020,6 +1025,12 @@ static int npcm7xx_pwm_fan_probe(struct platform_device *pdev) msecs_to_jiffies(NPCM7XX_FAN_POLL_TIMER_200MS); timer_setup(&data->fan_timer, npcm7xx_fan_polling, 0); + ret = devm_add_action_or_reset(dev, + npcm7xx_fan_cleanup, + &data->fan_timer); + if (ret) + return ret; + add_timer(&data->fan_timer); break; }