HI Bart,
On Wed, Sep 4, 2024 at 1:19 PM Bart Van Assche <bvanassche@xxxxxxx> wrote:
>
> Suppress the following lockdep complaint:
>
> INFO: trying to register non-static key.
> The code is fine but needs lockdep annotation, or maybe
> you didn't initialize this object before use?
> turning off the locking correctness validator.
>
> Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
> Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Cc: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: fde0aa6c175a ("usb: common: Small class for USB role switches")
> Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
> ---
> drivers/usb/roles/class.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
> index d7aa913ceb8a..f648ce3dd9b5 100644
> --- a/drivers/usb/roles/class.c
> +++ b/drivers/usb/roles/class.c
> @@ -21,6 +21,7 @@ static const struct class role_class = {
>
> struct usb_role_switch {
> struct device dev;
> + struct lock_class_key key;
> struct mutex lock; /* device lock*/
> struct module *module; /* the module this device depends on */
> enum usb_role role;
> @@ -326,6 +327,8 @@ static void usb_role_switch_release(struct device *dev)
> {
> struct usb_role_switch *sw = to_role_switch(dev);
>
> + mutex_destroy(&sw->lock);
> + lockdep_unregister_key(&sw->key);
> kfree(sw);
> }
>
> @@ -364,7 +367,8 @@ usb_role_switch_register(struct device *parent,
> if (!sw)
> return ERR_PTR(-ENOMEM);
>
> - mutex_init(&sw->lock);
> + lockdep_register_key(&sw->key);
> + __mutex_init(&sw->lock, "usb_role_switch_desc::lock", &sw->key);
https://lore.kernel.org/all/ZsiYRAJST%2F2hAju1@xxxxxxxxxxxxxxxxx/ was
already accepted and is perhaps better than what you are suggesting as
it does not use the internal methods of mutex_init(). CCing Amit as
well so that his patch can be submitted to stable trees as well.
>
> sw->allow_userspace_control = desc->allow_userspace_control;
> sw->usb2_port = desc->usb2_port;
>
Thanks,
Badhri
