[PATCH 4.15 080/168] net/mlx5e: IPoIB, Use correct timestamp in child receive flow

[Greg Kroah-Hartman]

4.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Feras Daoud <ferasda@xxxxxxxxxxxx>


[ Upstream commit 36e564b76f1862914ad32c35bab433e07da2ebf8 ]

The current implementation takes the child timestamp object from
the parent since the rq in mlx5i_complete_rx_cqe belongs to the parent.
This change fixes the issue by taking the correct timestamp.

Fixes: 7e7f4780c340 ("net/mlx5e: IPoIB, Use hash-table to map between QPN to child netdev")
Signed-off-by: Feras Daoud <ferasda@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -1196,7 +1196,9 @@ static inline void mlx5i_complete_rx_cqe
 					 u32 cqe_bcnt,
 					 struct sk_buff *skb)
 {
+	struct hwtstamp_config *tstamp;
 	struct net_device *netdev;
+	struct mlx5e_priv *priv;
 	char *pseudo_header;
 	u32 qpn;
 	u8 *dgid;
@@ -1215,6 +1217,9 @@ static inline void mlx5i_complete_rx_cqe
 		return;
 	}
 
+	priv = mlx5i_epriv(netdev);
+	tstamp = &priv->tstamp;
+
 	g = (be32_to_cpu(cqe->flags_rqpn) >> 28) & 3;
 	dgid = skb->data + MLX5_IB_GRH_DGID_OFFSET;
 	if ((!g) || dgid[0] != 0xff)
@@ -1235,7 +1240,7 @@ static inline void mlx5i_complete_rx_cqe
 	skb->ip_summed = CHECKSUM_COMPLETE;
 	skb->csum = csum_unfold((__force __sum16)cqe->check_sum);
 
-	if (unlikely(mlx5e_rx_hw_stamp(rq->tstamp)))
+	if (unlikely(mlx5e_rx_hw_stamp(tstamp)))
 		skb_hwtstamps(skb)->hwtstamp =
 				mlx5_timecounter_cyc2time(rq->clock, get_cqe_ts(cqe));