net/mlx4_en: Fix bad WQE issue

Single send WQE in RX buffer should be stamped with software
ownership in order to prevent the flow of QP in error in FW
once UPDATE_QP is called.

Fixes: 9f519f68cfff ('mlx4_en: Not using Shared Receive Queues')
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 3c37e216bbf324d527a27bee53418f2ecd62e724..eac527e25ec902c2a586e9952272b9e8e599e2c8 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -445,8 +445,14 @@ int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
                ring->cqn = priv->rx_cq[ring_ind]->mcq.cqn;
 
                ring->stride = stride;
-               if (ring->stride <= TXBB_SIZE)
+               if (ring->stride <= TXBB_SIZE) {
+                       /* Stamp first unused send wqe */
+                       __be32 *ptr = (__be32 *)ring->buf;
+                       __be32 stamp = cpu_to_be32(1 << STAMP_SHIFT);
+                       *ptr = stamp;
+                       /* Move pointer to start of rx section */
                        ring->buf += TXBB_SIZE;
+               }
 
                ring->log_stride = ffs(ring->stride) - 1;
                ring->buf_size = ring->size * ring->stride;