Re: Correct usage of dev_base_lock in 2020

Vladimir Oltean
2020-11-30T19:47:23Z

On Mon, Nov 30, 2020 at 08:22:01PM +0100, Eric Dumazet wrote:
> And ?
>
> A bonding device can absolutely maintain a private list, ready for
> bonding ndo_get_stats() use, regardless
> of register/unregister logic.
>
> bond_for_each_slave() is simply a macro, you can replace it by something else.

Also, coming to take the comment at face value.
Can it really? How? Freeing a net_device at unregister time happens
after an RCU grace period. So whatever the bonding driver does to keep a
private list of slave devices, those pointers need to be under RCU
protection. And that doesn't help with the sleepable context that we're
looking for.