Revert "IB/mlx4: Return EAGAIN for any error in mlx4_ib_poll_one"

By Mellanox HW design and SW implementation, poll_cq never
fails and returns errors, so all these printks are to catch ULP bugs.

In case of such bug, the reverted patch will cause reentry of the
function, resulting in a printk storm.

This reverts commit 5412352f ("IB/mlx4: Return EAGAIN for any error in mlx4_ib_poll_one")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx4/cq.c

@@ -690,7 +690,7 @@ static int mlx4_ib_poll_one(struct mlx4_ib_cq *cq,
 	if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) == MLX4_OPCODE_NOP &&
 		     is_send)) {
 		pr_warn("Completion for NOP opcode detected!\n");
-		return -EAGAIN;
+		return -EINVAL;
 	}
 
 	/* Resize CQ in progress */
@@ -721,7 +721,7 @@ static int mlx4_ib_poll_one(struct mlx4_ib_cq *cq,
 		if (unlikely(!mqp)) {
 			pr_warn("CQ %06x with entry for unknown QPN %06x\n",
 			       cq->mcq.cqn, be32_to_cpu(cqe->vlan_my_qpn) & MLX4_CQE_QPN_MASK);
-			return -EAGAIN;
+			return -EINVAL;
 		}
 
 		*cur_qp = to_mibqp(mqp);
@@ -739,7 +739,7 @@ static int mlx4_ib_poll_one(struct mlx4_ib_cq *cq,
 		if (unlikely(!msrq)) {
 			pr_warn("CQ %06x with entry for unknown SRQN %06x\n",
 				cq->mcq.cqn, srq_num);
-			return -EAGAIN;
+			return -EINVAL;
 		}
 	}