From 32b0d28145ef610bf34fadc076a6ffb7e4f075cd Mon Sep 17 00:00:00 2001
From: hselasky <hselasky@FreeBSD.org>
Date: Tue, 8 Aug 2017 11:49:36 +0000
Subject: [PATCH] Make sure the received IP header gets 32-bit aligned for
 short packets in the mlx5en(4) driver.

MFC after:		1 week
Sponsored by:		Mellanox Technologies
---
 sys/dev/mlx5/mlx5_en/mlx5_en_rx.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c b/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c
index 4d29b2397e64..7c490deba86d 100644
--- a/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c
+++ b/sys/dev/mlx5/mlx5_en/mlx5_en_rx.c
@@ -355,9 +355,11 @@ mlx5e_poll_rx_cq(struct mlx5e_rq *rq, int budget)
 			rq->stats.wqe_err++;
 			goto wq_ll_pop;
 		}
-
-		if (MHLEN >= byte_cnt &&
+		if ((MHLEN - MLX5E_NET_IP_ALIGN) >= byte_cnt &&
 		    (mb = m_gethdr(M_NOWAIT, MT_DATA)) != NULL) {
+			/* get IP header aligned */
+			mb->m_data += MLX5E_NET_IP_ALIGN;
+
 			bcopy(rq->mbuf[wqe_counter].data, mtod(mb, caddr_t),
 			    byte_cnt);
 		} else {