[RFC PATCH net-next 1/5] net: core: generic XDP support for stacked device

[Jason Wang]

Stacked device usually change skb->dev to its own and return
RX_HANDLER_ANOTHER during rx handler processing. But we don't call
generic XDP routine at that time, this means it can't work for stacked
device.

Fixing this by calling netif_do_generic_xdp() if rx handler returns
RX_HANDLER_ANOTHER. This allows us to do generic XDP on stacked device
e.g macvlan.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
 net/core/dev.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/core/dev.c b/net/core/dev.c
index 605c66e..a77ce08 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4822,6 +4822,11 @@ static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc,
 			ret = NET_RX_SUCCESS;
 			goto out;
 		case RX_HANDLER_ANOTHER:
+			ret = netif_do_generic_xdp(skb);
+			if (ret != XDP_PASS) {
+				ret = NET_RX_SUCCESS;
+				goto out;
+			}
 			goto another_round;
 		case RX_HANDLER_EXACT:
 			deliver_exact = true;
-- 
2.7.4