is_static_object
bool (*is_static_object)(void *addr);
.is_static_object = rcuhead_is_static_object,
.is_static_object = timer_is_static_object,
.is_static_object = work_is_static_object,
.is_static_object = is_static_object,
if (!descr->is_static_object || !descr->is_static_object(addr))