On Wed, Apr 07, 2021 at 04:15:53PM +0800, Weihang Li wrote: > It's ok if the refcount of cm_id is zero when release the reference of it, > there is no need to call BUG_ON. Huh? No it isn't. If you want to remove this BUG_ON then convert this to a refcount_t and rely on refcount debugging instead. Jason