In
adm9240_read()
adm9240_fan_read()
adm9240_write_fan_div(),
it assumes that the caller of adm9240_write_fan_div() must hold
data->update_lock. Otherwise, it may cause data races when data is
updated by other threads.
Signed-off-by: Li Zhong <floridsleeves@gmail.com>
Link: https://lore.kernel.org/r/20220924001751.1726369-1-floridsleeves@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
switch (attr) {
case hwmon_fan_input:
switch (attr) {
case hwmon_fan_input:
+ mutex_lock(&data->update_lock);
err = regmap_read(data->regmap, ADM9240_REG_FAN(channel), ®val);
err = regmap_read(data->regmap, ADM9240_REG_FAN(channel), ®val);
+ if (err < 0) {
+ mutex_unlock(&data->update_lock);
if (regval == 255 && data->fan_div[channel] < 3) {
/* adjust fan clock divider on overflow */
err = adm9240_write_fan_div(data, channel,
++data->fan_div[channel]);
if (regval == 255 && data->fan_div[channel] < 3) {
/* adjust fan clock divider on overflow */
err = adm9240_write_fan_div(data, channel,
++data->fan_div[channel]);
+ if (err) {
+ mutex_unlock(&data->update_lock);
}
*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
}
*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
+ mutex_unlock(&data->update_lock);
break;
case hwmon_fan_div:
*val = BIT(data->fan_div[channel]);
break;
case hwmon_fan_div:
*val = BIT(data->fan_div[channel]);