On Mon, 22 Jan 2024 at 23:17, Maciej Fijalkowski
<maciej.fijalkowski@xxxxxxxxx> wrote:
>
> xdp_rxq_info struct can be registered by drivers via two functions -
> xdp_rxq_info_reg() and __xdp_rxq_info_reg(). The latter one allows
> drivers that support XDP multi-buffer to set up xdp_rxq_info::frag_size
> which in turn will make it possible to grow the packet via
> bpf_xdp_adjust_tail() BPF helper.
>
> Currently, ice registers xdp_rxq_info in two spots:
> 1) ice_setup_rx_ring() // via xdp_rxq_info_reg(), BUG
> 2) ice_vsi_cfg_rxq() // via __xdp_rxq_info_reg(), OK
>
> Cited commit under fixes tag took care of setting up frag_size and
> updated registration scheme in 2) but it did not help as
> 1) is called before 2) and as shown above it uses old registration
> function. This means that 2) sees that xdp_rxq_info is already
> registered and never calls __xdp_rxq_info_reg() which leaves us with
> xdp_rxq_info::frag_size being set to 0.
>
> To fix this misbehavior, simply remove xdp_rxq_info_reg() call from
> ice_setup_rx_ring().
Acked-by: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
> Fixes: 2fba7dc5157b ("ice: Add support for XDP multi-buffer on Rx side")
> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
> ---
> drivers/net/ethernet/intel/ice/ice_txrx.c | 5 -----
> 1 file changed, 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
> index 1760e81379cc..765aea630a1f 100644
> --- a/drivers/net/ethernet/intel/ice/ice_txrx.c
> +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
> @@ -513,11 +513,6 @@ int ice_setup_rx_ring(struct ice_rx_ring *rx_ring)
> if (ice_is_xdp_ena_vsi(rx_ring->vsi))
> WRITE_ONCE(rx_ring->xdp_prog, rx_ring->vsi->xdp_prog);
>
> - if (rx_ring->vsi->type == ICE_VSI_PF &&
> - !xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
> - if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
> - rx_ring->q_index, rx_ring->q_vector->napi.napi_id))
> - goto err;
> return 0;
>
> err:
> --
> 2.34.1
>
>
