[PATCH 1/2] net: mana: Add handling of CQE_RX_TRUNCATED

[Tim Gardner]

From: Haiyang Zhang <haiyangz at microsoft.com>

The proper way to drop this kind of CQE is advancing rxq tail
without indicating the packet to the upper network layer.

Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com>
Reviewed-by: Dexuan Cui <decui at microsoft.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
(cherry picked from commit e4b7621982d29f26ff4d39af389e5e675a4ffed4 linux-next next-20220208)
Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
---
 drivers/net/ethernet/microsoft/mana/mana_en.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 987e11c02f727..5203f8824231a 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -991,8 +991,10 @@ static void mana_process_rx_cqe(struct mana_rxq *rxq, struct mana_cq *cq,
 		break;
 
 	case CQE_RX_TRUNCATED:
-		netdev_err(ndev, "Dropped a truncated packet\n");
-		return;
+		++ndev->stats.rx_dropped;
+		rxbuf_oob = &rxq->rx_oobs[rxq->buf_index];
+		netdev_warn_once(ndev, "Dropped a truncated packet\n");
+		goto drop;
 
 	case CQE_RX_COALESCED_4:
 		netdev_err(ndev, "RX coalescing is unsupported\n");
@@ -1054,6 +1056,7 @@ static void mana_process_rx_cqe(struct mana_rxq *rxq, struct mana_cq *cq,
 
 	mana_rx_skb(old_buf, oob, rxq);
 
+drop:
 	mana_move_wq_tail(rxq->gdma_rq, rxbuf_oob->wqe_inf.wqe_size_in_bu);
 
 	mana_post_pkt_rxq(rxq);
-- 
2.35.1