Re: [PATCH] usb: roles: Fix a false positive recursive locking complaint

[Bart Van Assche <bvanassche@acm.org>]

On 9/4/24 2:00 PM, Badhri Jagan Sridharan wrote:
> https://lore.kernel.org/all/ZsiYRAJST%2F2hAju1@kuha.fi.intel.com/ was
> already accepted

Thanks, I hadn't noticed this yet.

> and is perhaps better than what you are suggesting as
> it does not use the internal methods of mutex_init().

Although I do not have a strong opinion about which patch is sent to
Linus, I think my patch has multiple advantages compared to the patch
mentioned above:
- Cleaner. lockdep_set_class() is not used. Hence, it is not possible
   that the wrong lockdep key is used (the one assigned by
   mutex_init()).
- The lock_class_key declaration occurs close to the sw->lock
   declaration.
- The lockdep_register_key() call occurs close to __mutex_init() call
   that uses the registered key.
- Needs less memory in debug kernels. The advantage of __mutex_init()
   compared to mutex_init() is that it does not allocate (static) memory
   for a lockdep key.

Thanks,

Bart.