Re: [PATCH] thermal: fix multiple disbalanced device node counters

[Vladimir Zapolskiy <vz@mleia.com>]

Dear Eduardo, Zhang,

On 29.09.2014 02:47, Vladimir Zapolskiy wrote:
> Here on function return all temporarily used device nodes shall
> decrement their usage counter. The problems are found with device
> nodes allocated by for_each_child_of_node(), of_parse_phandle()
> and of_find_node_by_name(), fix all problems at once.

ping. The bugfix is quite straightforward, please review.

> Signed-off-by: Vladimir Zapolskiy<vz@mleia.com>
> Cc: devicetree@vger.kernel.org
> Cc: Zhang Rui<rui.zhang@intel.com>
> Cc: Eduardo Valentin<edubezval@gmail.com>
> ---
>   drivers/thermal/of-thermal.c |   40 ++++++++++++++++++++++++++++++++--------
>   1 file changed, 32 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
> index f8eb625..62143ba 100644
> --- a/drivers/thermal/of-thermal.c
> +++ b/drivers/thermal/of-thermal.c
> @@ -387,15 +387,18 @@ thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
>   				int (*get_trend)(void *, long *))
>   {
>   	struct device_node *np, *child, *sensor_np;
> +	struct thermal_zone_device *tzd = ERR_PTR(-ENODEV);
>
>   	np = of_find_node_by_name(NULL, "thermal-zones");
>   	if (!np)
>   		return ERR_PTR(-ENODEV);
>
> -	if (!dev || !dev->of_node)
> +	if (!dev || !dev->of_node) {
> +		of_node_put(np);
>   		return ERR_PTR(-EINVAL);
> +	}
>
> -	sensor_np = dev->of_node;
> +	sensor_np = of_node_get(dev->of_node);
>
>   	for_each_child_of_node(np, child) {
>   		struct of_phandle_args sensor_specs;
> @@ -422,16 +425,21 @@ thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
>   		}
>
>   		if (sensor_specs.np == sensor_np&&  id == sensor_id) {
> -			of_node_put(np);
> -			return thermal_zone_of_add_sensor(child, sensor_np,
> -							  data,
> -							  get_temp,
> -							  get_trend);
> +			tzd = thermal_zone_of_add_sensor(child, sensor_np,
> +							 data,
> +							 get_temp,
> +							 get_trend);
> +			of_node_put(sensor_specs.np);
> +			of_node_put(child);
> +			goto exit;
>   		}
> +		of_node_put(sensor_specs.np);
>   	}
> +exit:
> +	of_node_put(sensor_np);
>   	of_node_put(np);
>
> -	return ERR_PTR(-ENODEV);
> +	return tzd;
>   }
>   EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
>
> @@ -623,6 +631,7 @@ static int thermal_of_populate_trip(struct device_node *np,
>
>   	/* Required for cooling map matching */
>   	trip->np = np;
> +	of_node_get(np);
>
>   	return 0;
>   }
> @@ -730,9 +739,14 @@ finish:
>   	return tz;
>
>   free_tbps:
> +	for (i = 0; i<  tz->num_tbps; i++)
> +		of_node_put(tz->tbps[i].cooling_device);
>   	kfree(tz->tbps);
>   free_trips:
> +	for (i = 0; i<  tz->ntrips; i++)
> +		of_node_put(tz->trips[i].np);
>   	kfree(tz->trips);
> +	of_node_put(gchild);
>   free_tz:
>   	kfree(tz);
>   	of_node_put(child);
> @@ -742,7 +756,13 @@ free_tz:
>
>   static inline void of_thermal_free_zone(struct __thermal_zone *tz)
>   {
> +	int i;
> +
> +	for (i = 0; i<  tz->num_tbps; i++)
> +		of_node_put(tz->tbps[i].cooling_device);
>   	kfree(tz->tbps);
> +	for (i = 0; i<  tz->ntrips; i++)
> +		of_node_put(tz->trips[i].np);
>   	kfree(tz->trips);
>   	kfree(tz);
>   }
> @@ -814,10 +834,13 @@ int __init of_parse_thermal_zones(void)
>   			/* attempting to build remaining zones still */
>   		}
>   	}
> +	of_node_put(np);
>
>   	return 0;
>
>   exit_free:
> +	of_node_put(child);
> +	of_node_put(np);
>   	of_thermal_free_zone(tz);
>
>   	/* no memory available, so free what we have built */
> @@ -859,4 +882,5 @@ void of_thermal_destroy_zones(void)
>   		kfree(zone->ops);
>   		of_thermal_free_zone(zone->devdata);
>   	}
> +	of_node_put(np);
>   }

--
With best wishes,
Vladimir