Re: [PATCH net v2] atm: mpoa: keep mpc->dev referenced across mpoad restart

[Shuvam Pandey]

Hi Paolo,

> Since this patch removes the dev_put(mpc->dev) here to defer the
> netdevice reference release to the NETDEV_UNREGISTER event, does this
> introduce a leak of the netdevice reference on module unload?
> ...
> Should a dev_put() be added in the module exit function atm_mpoa_cleanup()?

For the netdevice reference itself, I don't think a cleanup-side
dev_put() is needed here.

unregister_netdevice_notifier() synthesizes NETDEV_UNREGISTER to the
removed notifier, and mpoa_event_listener() already drops mpc->dev in
that path. So removing the dev_put() from mpoad_close() should not leak
the netdevice reference on module unload.

I'll fold that into v3 together with the full decoded backtrace, the
syzbot console link, and a clearer lifetime explanation.

Shuvam