When an end-of-conversion interrupt is received after performing a
single-shot reading of the light sensor, the driver was waking up the
result ready queue before checking opt->ok_to_ignore_lock to determine
if it should unlock the mutex. The problem occurred in the case where
the other thread woke up and changed the value of opt->ok_to_ignore_lock
to false prior to the interrupt thread performing its read of the
variable. In this case, the mutex would be unlocked twice.
Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Andreas Dannenberg <dannenberg@ti.com>
Fixes:
94a9b7b1809f ("iio: light: add support for TI's opt3001 light sensor")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
struct iio_dev *iio = _iio;
struct opt3001 *opt = iio_priv(iio);
int ret;
struct iio_dev *iio = _iio;
struct opt3001 *opt = iio_priv(iio);
int ret;
+ bool wake_result_ready_queue = false;
if (!opt->ok_to_ignore_lock)
mutex_lock(&opt->lock);
if (!opt->ok_to_ignore_lock)
mutex_lock(&opt->lock);
}
opt->result = ret;
opt->result_ready = true;
}
opt->result = ret;
opt->result_ready = true;
- wake_up(&opt->result_ready_queue);
+ wake_result_ready_queue = true;
}
out:
if (!opt->ok_to_ignore_lock)
mutex_unlock(&opt->lock);
}
out:
if (!opt->ok_to_ignore_lock)
mutex_unlock(&opt->lock);
+ if (wake_result_ready_queue)
+ wake_up(&opt->result_ready_queue);
+