[dpdk-stable] [PATCH] net/virtio: fix device configure without jumbo Rx offload

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

From: Ivan Ilchenko <Ivan.Ilchenko@oktetlabs.ru>

Use max-pkt-len only if jumbo frames offload is requested
since otherwise this field isn't valid.

Fixes: 8b90e4358112 ("net/virtio: set offload flag for jumbo frames")
Fixes: 4e8169eb0d2d ("net/virtio: fix Rx scatter offload")
Cc: stable@dpdk.org

Signed-off-by: Ivan Ilchenko <ivan.ilchenko@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
---
 drivers/net/virtio/virtio_ethdev.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index e58085a2c9..9bce6833db 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -2099,10 +2099,14 @@ virtio_dev_configure(struct rte_eth_dev *dev)
 			return ret;
 	}
 
-	if (rxmode->max_rx_pkt_len > hw->max_mtu + ether_hdr_len)
+	if ((rx_offloads & DEV_RX_OFFLOAD_JUMBO_FRAME) &&
+	    (rxmode->max_rx_pkt_len > hw->max_mtu + ether_hdr_len))
 		req_features &= ~(1ULL << VIRTIO_NET_F_MTU);
 
-	hw->max_rx_pkt_len = rxmode->max_rx_pkt_len;
+	if (rx_offloads & DEV_RX_OFFLOAD_JUMBO_FRAME)
+		hw->max_rx_pkt_len = rxmode->max_rx_pkt_len;
+	else
+		hw->max_rx_pkt_len = ether_hdr_len + dev->data->mtu;
 
 	if (rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
 			   DEV_RX_OFFLOAD_TCP_CKSUM))
-- 
2.30.2