[net 05/10] net/mlx5e: XDP, Avoid checksum complete when XDP prog is loaded

[Saeed Mahameed]

XDP programs might change packets data contents which will make the
reported skb checksum (checksum complete) invalid.

When XDP programs are loaded/unloaded set/clear rx RQs
MLX5E_RQ_STATE_NO_CSUM_COMPLETE flag.

Fixes: 86994156c736 ("net/mlx5e: XDP fast RX drop bpf programs support")
Reviewed-by: Tariq Toukan <tar...@mellanox.com>
Signed-off-by: Saeed Mahameed <sae...@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 3 ++-
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c    | 6 +++++-
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c      | 3 ++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index 5efce4a3ff79..76a3d01a489e 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -1768,7 +1768,8 @@ static int set_pflag_rx_no_csum_complete(struct 
net_device *netdev, bool enable)
        struct mlx5e_channel *c;
        int i;
 
-       if (!test_bit(MLX5E_STATE_OPENED, &priv->state))
+       if (!test_bit(MLX5E_STATE_OPENED, &priv->state) ||
+           priv->channels.params.xdp_prog)
                return 0;
 
        for (i = 0; i < channels->num; i++) {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 002e2adb3722..4187c43b20ad 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -951,7 +951,11 @@ static int mlx5e_open_rq(struct mlx5e_channel *c,
        if (params->rx_dim_enabled)
                __set_bit(MLX5E_RQ_STATE_AM, &c->rq.state);
 
-       if (MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_NO_CSUM_COMPLETE))
+       /* We disable csum_complete when XDP is enabled since
+        * XDP programs might manipulate packets which will render
+        * skb->checksum incorrect.
+        */
+       if (MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_NO_CSUM_COMPLETE) || c->xdp)
                __set_bit(MLX5E_RQ_STATE_NO_CSUM_COMPLETE, &c->rq.state);
 
        return 0;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 3dde5c7e0739..91af48344743 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -752,7 +752,8 @@ static inline void mlx5e_handle_csum(struct net_device 
*netdev,
                return;
        }
 
-       if (unlikely(test_bit(MLX5E_RQ_STATE_NO_CSUM_COMPLETE, &rq->state)))
+       /* True when explicitly set via priv flag, or XDP prog is loaded */
+       if (test_bit(MLX5E_RQ_STATE_NO_CSUM_COMPLETE, &rq->state))
                goto csum_unnecessary;
 
        /* CQE csum doesn't cover padding octets in short ethernet
-- 
2.20.1