On Tue, May 24, 2022 at 8:14 PM Dmitry Rokosov <DDRokosov@xxxxxxxxxxxxxx> wrote: > > IIO trigger interface function iio_trigger_get() should be called after > iio_trigger_register() (or its devm analogue) strictly, because of > iio_trigger_get() acquires module refcnt based on the trigger->owner > pointer, which is initialized inside iio_trigger_register() to > THIS_MODULE. > If this call order is wrong, the next iio_trigger_put() (from sysfs > callback or "delete module" path) will dereference "default" module > refcnt, which is incorrect behaviour. Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> > Fixes: f1f065d7ac30 ("iio: chemical: ccs811: Add support for data ready trigger") > Signed-off-by: Dmitry Rokosov <ddrokosov@xxxxxxxxxxxxxx> > --- > drivers/iio/chemical/ccs811.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/chemical/ccs811.c b/drivers/iio/chemical/ccs811.c > index 847194fa1e46..80ef1aa9aae3 100644 > --- a/drivers/iio/chemical/ccs811.c > +++ b/drivers/iio/chemical/ccs811.c > @@ -499,11 +499,11 @@ static int ccs811_probe(struct i2c_client *client, > > data->drdy_trig->ops = &ccs811_trigger_ops; > iio_trigger_set_drvdata(data->drdy_trig, indio_dev); > - indio_dev->trig = data->drdy_trig; > - iio_trigger_get(indio_dev->trig); > ret = iio_trigger_register(data->drdy_trig); > if (ret) > goto err_poweroff; > + > + indio_dev->trig = iio_trigger_get(data->drdy_trig); > } > > ret = iio_triggered_buffer_setup(indio_dev, NULL, > -- > 2.36.0 -- With Best Regards, Andy Shevchenko