net/mlx5: fix packet inline on Tx queue wraparound

Inlining a packet to WQE that cross the WQ wraparound, i.e. the WQE
starts on the end of the ring and ends on the beginning, is not
supported and blocked by the data path logic.

However, in case of TSO, an extra inline header is required before
inlining. This inline header is not taken into account when checking if
there is enough room left for the required inline size.
On some corner cases were
(ring_tailroom - inline header) < inline size < ring_tailroom ,
this can lead to WQE being written outsize of the ring buffer.

Fixing it by always assuming the worse case that inline of packet will
require the inline header.

Fixes: 3f13f8c23a7c ("net/mlx5: support hardware TSO")
Cc: stable@dpdk.org
Signed-off-by: Shahaf Shuler <shahafs@mellanox.com>
Acked-by: Yongseok Koh <yskoh@mellanox.com>

diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index baa4079..38ce0e2 100644 (file)
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -693,7 +693,8 @@ pkt_inline:
                                                   RTE_CACHE_LINE_SIZE);
                        copy_b = (addr_end > addr) ?
                                 RTE_MIN((addr_end - addr), length) : 0;
-                       if (copy_b && ((end - (uintptr_t)raw) > copy_b)) {
+                       if (copy_b && ((end - (uintptr_t)raw) >
+                                      (copy_b + sizeof(inl)))) {
                                /*
                                 * One Dseg remains in the current WQE.  To
                                 * keep the computation positive, it is