> Modifying skb->len & data_len doesn't look correct. Issue is not critical
> we just pad 2 times, except first padding is not filled with zeros.
>
> However I'm not sure if we should not add pad to all skb's in frags
> list.
Hi Stanislaw,
IIRC the first packet of a A-MSDU burst keeps track of the burst length
so if we add the a pad to last one we need to update the skb->len/data_len
of the first one. No need to pad all skbs in the frag list, just last one
Regards,
Lorenzo
> Additionally remove unlikely(pad) condition, we always pad for at least
> four bytes what is needed by HW.
>
> Signed-off-by: Stanislaw Gruszka <sgruszka@xxxxxxxxxx>
> ---
> .../wireless/mediatek/mt76/mt76x02_usb_core.c | 22 +++++++------------
> 1 file changed, 8 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c b/drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c
> index dc2226c722dd..c7ca2d93720a 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c
> @@ -49,21 +49,15 @@ int mt76x02u_skb_dma_info(struct sk_buff *skb, int port, u32 flags)
> FIELD_PREP(MT_TXD_INFO_DPORT, port) | flags;
> put_unaligned_le32(info, skb_push(skb, sizeof(info)));
>
> - pad = round_up(skb->len, 4) + 4 - skb->len;
> - skb_walk_frags(skb, iter) {
> + skb_walk_frags(skb, iter)
> last = iter;
> - if (!iter->next) {
> - skb->data_len += pad;
> - skb->len += pad;
> - break;
> - }
> - }
> -
> - if (unlikely(pad)) {
> - if (skb_pad(last, pad))
> - return -ENOMEM;
> - __skb_put(last, pad);
> - }
> +
> + /* Add zero pad of 4 - 7 bytes at the end of buffer */
> + pad = round_up(skb->len, 4) + 4 - skb->len;
> + if (skb_pad(last, pad))
> + return -ENOMEM;
> + __skb_put(last, pad);
> +
> return 0;
> }
>
> --
> 2.19.2
>
