On 4/13/22 16:06, Lukasz Luba wrote:
On 4/13/22 15:58, Rafael J. Wysocki wrote:
On Fri, Mar 25, 2022 at 10:02 AM Lukasz Luba lukasz.luba@arm.com wrote:
Hi Kant,
On 3/25/22 07:30, Kant Fan wrote:
Fix access illegal address problem in following condition: There are muti devfreq cooling devices in system, some of them has em model but other does not, energy model ops such as state2power will append to global devfreq_cooling_ops when the cooling device with em model register. It makes the cooling device without em model also use devfreq_cooling_ops after appending when register later by of_devfreq_cooling_register_power() or of_devfreq_cooling_register().
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: stable@vger.kernel.org # 5.13+ Signed-off-by: Kant Fan kant@allwinnertech.com
drivers/thermal/devfreq_cooling.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c index 4310cb342a9f..d38a80adec73 100644 --- a/drivers/thermal/devfreq_cooling.c +++ b/drivers/thermal/devfreq_cooling.c @@ -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);
Thank you for updating it, LGTM
Reviewed-by: Lukasz Luba lukasz.luba@arm.com
Applied as 5.19 material.
Lukasz, this had a conflict with your EM series, please double check if my resolution in the bleeding-edge branch is correct.
OK, I'll let you know after I fetch and build that branch.
I've read the code and confirm you've do this correctly. I've also built that branch with ENERGY_MODEL and DEVFREQ_COOLING configs set - no issues observed. Later this week I would use it for some other development so I will test it as well.
Thank you for solving this!
Regards, Lukasz