There is warning reported by kobject lib in kobject_put():
kobject: '(null)' (00000000be81a546): is not initialized, yet kobject_put() is being called.
WARNING: CPU: 0 PID: 535 at lib/kobject.c:718 kobject_put+0x12c/0x180
Call Trace:
cdev_device_add
__iio_device_register
__devm_iio_device_register
tmp117_probe
If don't need to register chardev for most of IIO devices,
we just register them with device_add() only, and use device_del()
to unregister them.
Otherwise, when device_add() fails in internal and calls kobject_put()
in error handling path, it would report warning because the device
never be registered as chardev and there is no release function for it.
Fixes: 8ebaa3ff1e71 ("iio: core: register chardev only if needed")
Signed-off-by: Zeng Heng <zengheng4@xxxxxxxxxx>
---
drivers/iio/industrialio-core.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 151ff3993354..f4f48bda07f7 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1982,7 +1982,11 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
/* assign device groups now; they should be all registered now */
indio_dev->dev.groups = iio_dev_opaque->groups;
- ret = cdev_device_add(&iio_dev_opaque->chrdev, &indio_dev->dev);
+ if (iio_dev_opaque->attached_buffers_cnt || iio_dev_opaque->event_interface)
+ ret = cdev_device_add(&iio_dev_opaque->chrdev, &indio_dev->dev);
+ else
+ ret = device_add(&indio_dev->dev);
+
if (ret < 0)
goto error_unreg_eventset;
@@ -2008,7 +2012,10 @@ void iio_device_unregister(struct iio_dev *indio_dev)
{
struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
- cdev_device_del(&iio_dev_opaque->chrdev, &indio_dev->dev);
+ if (iio_dev_opaque->chrdev.kobj.state_initialized)
+ cdev_device_del(&iio_dev_opaque->chrdev, &indio_dev->dev);
+ else
+ device_del(&indio_dev->dev);
mutex_lock(&iio_dev_opaque->info_exist_lock);
--
2.25.1
