From:   Angus Chen <angus.chen@jaguarmicro.com>
To:     mst@redhat.com, jasowang@redhat.com, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        ast@kernel.org, daniel@iogearbox.net, hawk@kernel.org,
        john.fastabend@gmail.com
Cc:     virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
        Angus Chen <angus.chen@jaguarmicro.com>
Subject: [PATCH] virtio_net: Use NETDEV_TX_BUSY when has no buf to send
Date:   Thu,  9 Mar 2023 15:49:52 +0800
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Don't consume skb if virtqueue_add return -ENOSPC.

Signed-off-by: Angus Chen <angus.chen@jaguarmicro.com>
---
 drivers/net/virtio_net.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index fb5e68ed3ec2..4096ea3d2eb6 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1980,7 +1980,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 				 qnum, err);
 		dev->stats.tx_dropped++;
 		dev_kfree_skb_any(skb);
-		return NETDEV_TX_OK;
+		return (err == -ENOSPC) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
 	}
 
 	/* Don't wait up for transmitted skbs to be freed. */
-- 
2.25.1