net/mlx5e: Don't post fragmented MPWQE when RQ is disabled

ICO (Internal control operations) SQ (Send Queue) is closed/disabled
after RQ (Receive Queue).  After RQ is closed an ICO SQ completion
might post a fragmented MPWQE (Multi Packet Work Queue Element) into
that RQ.

As on regular RQ post, check if we are allowed to post to that
RQ (RQ is enabled). Cleanup in-progress UMR MPWQE on mlx5e_free_rx_descs
if needed.

Fixes: bc77b240b3c5 ('net/mlx5e: Add fragmented memory support for RX multi packet WQE')
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/en_main.c

@@ -534,6 +534,10 @@ static void mlx5e_free_rx_descs(struct mlx5e_rq *rq)
 	__be16 wqe_ix_be;
 	u16 wqe_ix;
 
+	/* UMR WQE (if in progress) is always at wq->head */
+	if (test_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state))
+		mlx5e_free_rx_fragmented_mpwqe(rq, &rq->wqe_info[wq->head]);
+
 	while (!mlx5_wq_ll_is_empty(wq)) {
 		wqe_ix_be = *wq->tail_next;
 		wqe_ix    = be16_to_cpu(wqe_ix_be);

drivers/net/ethernet/mellanox/mlx5/core/en_rx.c

@@ -506,6 +506,12 @@ void mlx5e_post_rx_fragmented_mpwqe(struct mlx5e_rq *rq)
 	struct mlx5e_rx_wqe *wqe = mlx5_wq_ll_get_wqe(wq, wq->head);
 
 	clear_bit(MLX5E_RQ_STATE_UMR_WQE_IN_PROGRESS, &rq->state);
+
+	if (unlikely(test_bit(MLX5E_RQ_STATE_FLUSH, &rq->state))) {
+		mlx5e_free_rx_fragmented_mpwqe(rq, &rq->wqe_info[wq->head]);
+		return;
+	}
+
 	mlx5_wq_ll_push(wq, be16_to_cpu(wqe->next.next_wqe_index));
 	rq->stats.mpwqe_frag++;