From: Kant Fan kant@allwinnertech.com
commit b947769b8f778db130aad834257fcaca25df2edc upstream.
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: 615510fe13bd2 ("thermal: devfreq_cooling: remove old power model and use EM") Cc: 5.13+ stable@vger.kernel.org # 5.13+ Signed-off-by: Kant Fan kant@allwinnertech.com Reviewed-by: Lukasz Luba lukasz.luba@arm.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/thermal/devfreq_cooling.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-)
--- a/drivers/thermal/devfreq_cooling.c +++ b/drivers/thermal/devfreq_cooling.c @@ -358,21 +358,28 @@ of_devfreq_cooling_register_power(struct 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 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 @@ free_table: 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_reg 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 t
kfree(dfc->freq_table); kfree(dfc); + kfree(ops); } EXPORT_SYMBOL_GPL(devfreq_cooling_unregister);