Commit b947769b authored by Kant Fan's avatar Kant Fan Committed by Rafael J. Wysocki
Browse files

thermal: devfreq_cooling: use local ops instead of global ops 



Fix access illegal address problem in following condition:

There are multiple devfreq cooling devices in system, some of them has
EM model but others do not. Energy model ops such as state2power will
append to global devfreq_cooling_ops when the cooling device with
EM model is registered. It makes the cooling device without EM model
also use devfreq_cooling_ops after appending when registered later by
of_devfreq_cooling_register_power() or of_devfreq_cooling_register().

The IPA governor regards the cooling devices without EM model as a power
actor, because they also have energy model ops, and will access illegal
address at dfc->em_pd when execute cdev->ops->get_requested_power,
cdev->ops->state2power or cdev->ops->power2state.

Fixes: 615510fe ("thermal: devfreq_cooling: remove old power model and use EM")
Cc: 5.13+ <stable@vger.kernel.org> # 5.13+
Signed-off-by: default avatarKant Fan <kant@allwinnertech.com>
Reviewed-by: default avatarLukasz Luba <lukasz.luba@arm.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 7bb732fe

drivers/thermal/devfreq_cooling.c

+18 −7
Original line number Diff line number Diff line
@@ -358,21 +358,28 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, 
	struct thermal_cooling_device *cdev;

	struct device *dev = df->dev.parent;

	struct devfreq_cooling_device *dfc;

	struct thermal_cooling_device_ops *ops;

	char *name;

	int err, num_opps;



	dfc = kzalloc(sizeof(*dfc), GFP_KERNEL);

	if (!dfc)

	ops = kmemdup(&devfreq_cooling_ops, sizeof(*ops), GFP_KERNEL);

	if (!ops)

		return ERR_PTR(-ENOMEM);



	dfc = kzalloc(sizeof(*dfc), GFP_KERNEL);

	if (!dfc) {

		err = -ENOMEM;

		goto free_ops;

	}



	dfc->devfreq = df;



	dfc->em_pd = em_pd_get(dev);

	if (dfc->em_pd) {

		devfreq_cooling_ops.get_requested_power =

		ops->get_requested_power =

			devfreq_cooling_get_requested_power;

		devfreq_cooling_ops.state2power = devfreq_cooling_state2power;

		devfreq_cooling_ops.power2state = devfreq_cooling_power2state;

		ops->state2power = devfreq_cooling_state2power;

		ops->power2state = devfreq_cooling_power2state;



		dfc->power_ops = dfc_power;
@@ -407,8 +414,7 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, 
	if (!name)

		goto remove_qos_req;



	cdev = thermal_of_cooling_device_register(np, name, dfc,

						  &devfreq_cooling_ops);

	cdev = thermal_of_cooling_device_register(np, name, dfc, ops);

	kfree(name);



	if (IS_ERR(cdev)) {
@@ -429,6 +435,8 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, 
	kfree(dfc->freq_table);

free_dfc:

	kfree(dfc);

free_ops:

	kfree(ops);



	return ERR_PTR(err);

}
@@ -510,11 +518,13 @@ EXPORT_SYMBOL_GPL(devfreq_cooling_em_register); 
void devfreq_cooling_unregister(struct thermal_cooling_device *cdev)

{

	struct devfreq_cooling_device *dfc;

	const struct thermal_cooling_device_ops *ops;

	struct device *dev;



	if (IS_ERR_OR_NULL(cdev))

		return;



	ops = cdev->ops;

	dfc = cdev->devdata;

	dev = dfc->devfreq->dev.parent;
@@ -525,5 +535,6 @@ void devfreq_cooling_unregister(struct thermal_cooling_device *cdev) 


	kfree(dfc->freq_table);

	kfree(dfc);

	kfree(ops);

}

EXPORT_SYMBOL_GPL(devfreq_cooling_unregister);