[dpdk-dev] [PATCH 1/8] net/bnxt: remove assert for zero data len in Tx path

[Kalesh A P <kalesh-anakkur.purayil@broadcom.com>]

From: Somnath Kotur <somnath.kotur@broadcom.com>

Currently the PMD tries to detect a potential 0 byte DMA by
using RTE_VERIFY.
But since RTE_VERIFY internally calls rte_panic() it is fatal to
the application and some applications want to avoid that.
So return an error from the bnxt xmit handler if such a bad pkt is
encountered by logging an error message, dumping the pkt header and
dump the current stack as well

Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
---
 drivers/net/bnxt/bnxt_txr.c | 29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/drivers/net/bnxt/bnxt_txr.c b/drivers/net/bnxt/bnxt_txr.c
index 7a7196a..67e0167 100644
--- a/drivers/net/bnxt/bnxt_txr.c
+++ b/drivers/net/bnxt/bnxt_txr.c
@@ -123,6 +123,26 @@ bnxt_xmit_need_long_bd(struct rte_mbuf *tx_pkt, struct bnxt_tx_queue *txq)
 	return false;
 }
 
+static bool
+bnxt_zero_data_len_tso_segsz(struct rte_mbuf *tx_pkt, uint8_t data_len_chk)
+{
+	const char *type_str = "Data len";
+	uint16_t len_to_check = tx_pkt->data_len;
+
+	if (data_len_chk == 0) {
+		type_str = "TSO Seg size";
+		len_to_check = tx_pkt->tso_segsz;
+	}
+
+	if (len_to_check == 0) {
+		PMD_DRV_LOG(ERR, "Error! Tx pkt %s == 0\n", type_str);
+		rte_pktmbuf_dump(stdout, tx_pkt, 64);
+		rte_dump_stack();
+		return true;
+	}
+	return false;
+}
+
 static uint16_t bnxt_start_xmit(struct rte_mbuf *tx_pkt,
 				struct bnxt_tx_queue *txq,
 				uint16_t *coal_pkts,
@@ -179,7 +199,8 @@ static uint16_t bnxt_start_xmit(struct rte_mbuf *tx_pkt,
 	}
 
 	/* Check non zero data_len */
-	RTE_VERIFY(tx_pkt->data_len);
+	if (unlikely(bnxt_zero_data_len_tso_segsz(tx_pkt, 1)))
+		return -EIO;
 
 	prod = RING_IDX(ring, txr->tx_raw_prod);
 	tx_buf = &txr->tx_buf_ring[prod];
@@ -256,7 +277,8 @@ static uint16_t bnxt_start_xmit(struct rte_mbuf *tx_pkt,
 			 */
 			txbd1->kid_or_ts_low_hdr_size = hdr_size >> 1;
 			txbd1->kid_or_ts_high_mss = tx_pkt->tso_segsz;
-			RTE_VERIFY(txbd1->kid_or_ts_high_mss);
+			if (unlikely(bnxt_zero_data_len_tso_segsz(tx_pkt, 0)))
+				return -EIO;
 
 		} else if ((tx_pkt->ol_flags & PKT_TX_OIP_IIP_TCP_UDP_CKSUM) ==
 			   PKT_TX_OIP_IIP_TCP_UDP_CKSUM) {
@@ -330,7 +352,8 @@ static uint16_t bnxt_start_xmit(struct rte_mbuf *tx_pkt,
 	m_seg = tx_pkt->next;
 	while (m_seg) {
 		/* Check non zero data_len */
-		RTE_VERIFY(m_seg->data_len);
+		if (unlikely(bnxt_zero_data_len_tso_segsz(m_seg, 1)))
+			return -EIO;
 		txr->tx_raw_prod = RING_NEXT(txr->tx_raw_prod);
 
 		prod = RING_IDX(ring, txr->tx_raw_prod);
-- 
2.10.1