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[0/3] thermal: Fix/cleanup error paths in __thermal_cooling_device_register()

Message ID cover.1674030722.git.viresh.kumar@linaro.org
Headers show
Series thermal: Fix/cleanup error paths in __thermal_cooling_device_register() | expand

Message

Viresh Kumar Jan. 18, 2023, 8:38 a.m. UTC 
Hi,

The error paths in __thermal_cooling_device_register() are trying to free
un-acquired resources, fix that and clean it up a bit.

Caleb, can you please test this? I have just build tested it for now.

--
Viresh

Viresh Kumar (3):
  thermal: core: call put_device() only after device_register() fails
  thermal: core: Move cdev cleanup to thermal_release()
  thermal: core: Use device_unregister() instead of device_del/put()

 drivers/thermal/thermal_core.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

Comments

Yang Yingliang Jan. 19, 2023, 8:25 a.m. UTC | #1 
On 2023/1/18 16:38, Viresh Kumar wrote:
> thermal_release() already frees cdev, let it do rest of the cleanup as
> well in order to simplify the error paths in
> __thermal_cooling_device_register().
>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
Reviewed-by: Yang Yingliang <yangyingliang@huawei.com>
>   drivers/thermal/thermal_core.c | 33 ++++++++++++++-------------------
>   1 file changed, 14 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 77bd47d976a2..1fb109a97ff6 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -774,6 +774,9 @@ static void thermal_release(struct device *dev)
>   	} else if (!strncmp(dev_name(dev), "cooling_device",
>   			    sizeof("cooling_device") - 1)) {
>   		cdev = to_cooling_device(dev);
> +		thermal_cooling_device_destroy_sysfs(cdev);
> +		kfree(cdev->type);
> +		ida_free(&thermal_cdev_ida, cdev->id);
>   		kfree(cdev);
>   	}
>   }
> @@ -909,23 +912,21 @@ __thermal_cooling_device_register(struct device_node *np,
>   	cdev->devdata = devdata;
>   
>   	ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
> -	if (ret) {
> -		kfree(cdev->type);
> -		goto out_ida_remove;
> -	}
> +	if (ret)
> +		goto out_cdev_type;
>   
>   	thermal_cooling_device_setup_sysfs(cdev);
>   
>   	ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
> -	if (ret) {
> -		kfree(cdev->type);
> -		thermal_cooling_device_destroy_sysfs(cdev);
> -		goto out_ida_remove;
> -	}
> +	if (ret)
> +		goto out_cooling_dev;
>   
>   	ret = device_register(&cdev->device);
> -	if (ret)
> -		goto out_kfree_type;
> +	if (ret) {
> +		/* thermal_release() handles rest of the cleanup */
> +		put_device(&cdev->device);
> +		return ERR_PTR(ret);
> +	}
>   
>   	/* Add 'this' new cdev to the global cdev list */
>   	mutex_lock(&thermal_list_lock);
> @@ -944,13 +945,10 @@ __thermal_cooling_device_register(struct device_node *np,
>   
>   	return cdev;
>   
> -out_kfree_type:
> +out_cooling_dev:
>   	thermal_cooling_device_destroy_sysfs(cdev);
> +out_cdev_type:
>   	kfree(cdev->type);
> -	put_device(&cdev->device);
> -
> -	/* thermal_release() takes care of the rest */
> -	cdev = NULL;
>   out_ida_remove:
>   	ida_free(&thermal_cdev_ida, id);
>   out_kfree_cdev:
> @@ -1111,10 +1109,7 @@ void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
>   
>   	mutex_unlock(&thermal_list_lock);
>   
> -	ida_free(&thermal_cdev_ida, cdev->id);
>   	device_del(&cdev->device);
> -	thermal_cooling_device_destroy_sysfs(cdev);
> -	kfree(cdev->type);
>   	put_device(&cdev->device);
>   }
>   EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
Yang Yingliang Jan. 19, 2023, 8:25 a.m. UTC | #2 
On 2023/1/18 16:38, Viresh Kumar wrote:
> Lets not open code device_unregister() unnecessarily.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
Reviewed-by: Yang Yingliang <yangyingliang@huawei.com>
>   drivers/thermal/thermal_core.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 1fb109a97ff6..9fb37c5d9c4f 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -1109,8 +1109,7 @@ void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
>   
>   	mutex_unlock(&thermal_list_lock);
>   
> -	device_del(&cdev->device);
> -	put_device(&cdev->device);
> +	device_unregister(&cdev->device);
>   }
>   EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
>