Re: [PATCH bpf V3 1/2] xsk: replace datagram_poll by sock_poll_wait

[Magnus Karlsson <magnus.karlsson@gmail.com>]

On Tue, Dec 1, 2020 at 3:00 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
>
> datagram_poll will judge the current socket status (EPOLLIN, EPOLLOUT)
> based on the traditional socket information (eg: sk_wmem_alloc), but
> this does not apply to xsk. So this patch uses sock_poll_wait instead of
> datagram_poll, and the mask is calculated by xsk_poll.
>

Could you please add a Fixes label here as this is a bug fix? It will
help the persons backporting this. Here is the line that goes just
above your Sign-off-by.

Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support")

Thanks: Magnus

> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
> ---
>  net/xdp/xsk.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
> index b7b039b..9bbfd8a 100644
> --- a/net/xdp/xsk.c
> +++ b/net/xdp/xsk.c
> @@ -471,11 +471,13 @@ static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len)
>  static __poll_t xsk_poll(struct file *file, struct socket *sock,
>                              struct poll_table_struct *wait)
>  {
> -       __poll_t mask = datagram_poll(file, sock, wait);
> +       __poll_t mask = 0;
>         struct sock *sk = sock->sk;
>         struct xdp_sock *xs = xdp_sk(sk);
>         struct xsk_buff_pool *pool;
>
> +       sock_poll_wait(file, sock, wait);
> +
>         if (unlikely(!xsk_is_bound(xs)))
>                 return mask;
>
> --
> 1.8.3.1
>