From: Jakub Kicinski Date: Wed, 28 Nov 2018 06:24:52 +0000 (-0800) Subject: nfp: avoid oversized TSO headers with metadata prepend X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=d7cc8252252f9e5b72975a3d498ba2ee08245740;p=openwrt%2Fstaging%2Fblogic.git nfp: avoid oversized TSO headers with metadata prepend In preparation for TSO over representors make sure the port id prepend will always fit in the frame. The current max header length is 255, which is ample, so assume worst case scenario of 8 byte prepend and save ourselves the conditionals. Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c index 9cc2c204baa3..3cb7dceca2d9 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c @@ -3284,7 +3284,10 @@ nfp_net_features_check(struct sk_buff *skb, struct net_device *dev, hdrlen = skb_inner_transport_header(skb) - skb->data + inner_tcp_hdrlen(skb); - if (unlikely(hdrlen > NFP_NET_LSO_MAX_HDR_SZ)) + /* Assume worst case scenario of having longest possible + * metadata prepend - 8B + */ + if (unlikely(hdrlen > NFP_NET_LSO_MAX_HDR_SZ - 8)) features &= ~NETIF_F_GSO_MASK; }