RE: [PATCH] hv_netvsc: Add comment of netvsc_xdp_xmit()

-----Original Message-----
From: Jiasheng Jiang <redacted>
Sent: Wednesday, October 13, 2021 9:26 PM
To: KY Srinivasan <kys@microsoft.com>; Haiyang Zhang
[off-list ref]; Stephen Hemminger [off-list ref];
wei.liu@kernel.org; Dexuan Cui [off-list ref];
davem@davemloft.net; kuba@kernel.org
Cc: linux-hyperv@vger.kernel.org; netdev@vger.kernel.org; linux-
kernel@vger.kernel.org; bpf@vger.kernel.org; Jiasheng Jiang
[off-list ref]
Subject: [PATCH] hv_netvsc: Add comment of netvsc_xdp_xmit()

Adding comment to avoid the misusing of netvsc_xdp_xmit().
Otherwise the value of skb->queue_mapping could be 0 and
then the return value of skb_get_rx_queue() could be MAX_U16
cause by overflow.

Fixes: 351e158 ("hv_netvsc: Add XDP support")
Signed-off-by: Jiasheng Jiang <redacted>
---
 drivers/net/hyperv/netvsc_drv.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/hyperv/netvsc_drv.c

b/drivers/net/hyperv/netvsc_drv.c
index f682a55..ac9529c 100644

--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c

@@ -803,6 +803,7 @@ void netvsc_linkstatus_callback(struct net_device

*net,
 	schedule_delayed_work(&ndev_ctx->dwork, 0);
 }

+/* This function should only be called after skb_record_rx_queue() */
 static void netvsc_xdp_xmit(struct sk_buff *skb, struct net_device
*ndev)
 {