# Re: \[PATCH bpf-next v2 4/8\] xsk: register XDP sockets at bind(), and add new AF\_XDP BPF helper

- From: Toke Høiland-Jørgensen \<hidden\>
- Date: 2021-01-20 14:05:19 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/01/7757886
- Thread: https://ratatoskr.run/netdev/2021/01/7757843/t.md

```text
Björn Töpel [ref] writes:

> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index c001766adcbc..bbc7d9a57262 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -3836,6 +3836,12 @@ union bpf_attr {
>   *	Return
>   *		A pointer to a struct socket on success or NULL if the file is
>   *		not a socket.
> + *
> + * long bpf_redirect_xsk(struct xdp_buff *xdp_md, u64 action)
> + *	Description
> + *		Redirect to the registered AF_XDP socket.
> + *	Return
> + *		**XDP_REDIRECT** on success, otherwise the action parameter is returned.
>   */

I think it would be better to make the second argument a 'flags'
argument and make values > XDP_TX invalid (like we do in
bpf_xdp_redirect_map() now). By allowing any value as return you lose
the ability to turn it into a flags argument later...

-Toke

```