diff options
| author | Dragos Tatulea <dtatulea@nvidia.com> | 2024-06-04 00:22:10 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-06-05 20:20:46 -0700 |
| commit | 083dbb54c4809bcd56c5c09360ee8c7760a55d71 (patch) | |
| tree | 6785844be6881bc406e82ea61c429dc241db2f82 | |
| parent | a64bbd8c286fa67319df73ce842e3f6c7b08b6f6 (diff) | |
net/mlx5e: SHAMPO, Disable gso_size for non GRO packets
When HW GRO is enabled, forwarding of packets is broken due to gso_size
being set incorrectly on non GRO packets.
Non GRO packets have a skb GRO count of 1. mlx5 always sets gso_size on
the skb, even for non GRO packets. It leans on the fact that gso_size is
normally reset in napi_gro_complete(). But this happens only for packets
from GRO'able protocols (TCP/UDP) that have a gro_receive() handler.
The problematic scenarios are:
1) Non GRO protocol packets are received, validate_xmit_skb() will drop
them (see EPROTONOSUPPORT in skb_mac_gso_segment()). The fix for
this case would be to not set gso_size at all for SHAMPO packets with
header size 0.
2) Packets from a GRO'ed protocol (TCP) are received but immediately
flushed because they are not GRO'able (TCP SYN for example).
mlx5e_shampo_update_hdr(), which updates the remaining GRO state on
the skb, is not called because skb GRO count is 1. The fix here would
be to always call mlx5e_shampo_update_hdr(), regardless of skb GRO
count. But this call is expensive
The unified fix for both cases is to reset gso_size before calling
napi_gro_receive(). It is a change that is more effective (no call to
mlx5e_shampo_update_hdr() necessary) and simple (smallest code
footprint).
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20240603212219.1037656-6-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c index b3ef0dd237298..a13fa760f948a 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c @@ -2267,6 +2267,8 @@ mlx5e_shampo_flush_skb(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe, bool match) mlx5e_shampo_align_fragment(skb, rq->mpwqe.log_stride_sz); if (NAPI_GRO_CB(skb)->count > 1) mlx5e_shampo_update_hdr(rq, cqe, match); + else + skb_shinfo(skb)->gso_size = 0; napi_gro_receive(rq->cq.napi, skb); rq->hw_gro_data->skb = NULL; } |