Re: [PATCH] driver core: change to_subsys_private() to use container_of_const()

[Rafael J. Wysocki]

On Wed, Jan 11, 2023 at 10:33 AM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> The macro to_subsys_private() needs to switch to using
> container_of_const() as it turned out to being incorrectly casting a
> const pointer to a non-const one.  Make this change and fix up the one
> offending user to be correctly handling a const pointer properly.
>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Reviewed-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>

> ---
>  drivers/base/base.h  | 2 +-
>  drivers/base/class.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/base/base.h b/drivers/base/base.h
> index 2e08258ce82e..3d1da1027206 100644
> --- a/drivers/base/base.h
> +++ b/drivers/base/base.h
> @@ -53,7 +53,7 @@ struct subsys_private {
>         struct kset glue_dirs;
>         struct class *class;
>  };
> -#define to_subsys_private(obj) container_of(obj, struct subsys_private, subsys.kobj)
> +#define to_subsys_private(obj) container_of_const(obj, struct subsys_private, subsys.kobj)
>
>  struct driver_private {
>         struct kobject kobj;
> diff --git a/drivers/base/class.c b/drivers/base/class.c
> index 86ec554cfe60..3366da9c3ff6 100644
> --- a/drivers/base/class.c
> +++ b/drivers/base/class.c
> @@ -64,7 +64,7 @@ static void class_release(struct kobject *kobj)
>
>  static const struct kobj_ns_type_operations *class_child_ns_type(const struct kobject *kobj)
>  {
> -       struct subsys_private *cp = to_subsys_private(kobj);
> +       const struct subsys_private *cp = to_subsys_private(kobj);
>         struct class *class = cp->class;
>
>         return class->ns_type;
> --
> 2.39.0
>