Shouldn't bus_register_notifier() take a notifier_fn_t (and int priority) directly and create its own struct notifier_block? Why does it expose its linked-list

Shouldn't bus_register_notifier() take a notifier_fn_t (and int priority) directly and create its own struct notifier_block? Why does it expose its linked-list node through its interface? I guess maybe that would make un-registration less ergonomic (assuming you have to handle duplicate entries in the list). But the peril of the bug described here seems worse.