When a device is stacked like (team, bonding, failsafe or netvsc) the
XDP generic program for the parent device is not called. In these
cases, the rx handler changes skb->dev to its own in the receive
handler, and returns RX_HANDLER_ANOTHER. Fix this by calling
do_xdp_generic if necessary before starting another round.
Review of all the places RX_HANDLER_ANOTHER is returned
show that the current devices do correctly change skb->dev.
There was an older patch that got abandoned that did the
same thing, this is just a rewrite.
Suggested-by: Jason Wang <jasow...@redhat.com>
Fixes: d445516966dc ("net: xdp: support xdp generic on virtual devices")
Signed-off-by: Stephen Hemminger <sthem...@microsoft.com>
Acked-by: Jason Wang <jasow...@redhat.com>
---
net/core/dev.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/net/core/dev.c b/net/core/dev.c
index b6b8505cfb3e..240d0b2de1a8 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4921,6 +4921,16 @@ static int __netif_receive_skb_core(struct sk_buff *skb,
bool pfmemalloc,
ret = NET_RX_SUCCESS;
goto out;
case RX_HANDLER_ANOTHER:
+ if (static_branch_unlikely(&generic_xdp_needed_key)) {
+ struct bpf_prog *xdp_prog;
+
+ xdp_prog = rcu_dereference(skb->dev->xdp_prog);
+ ret = do_xdp_generic(xdp_prog, skb);
+ if (ret != XDP_PASS) {
+ ret = NET_RX_SUCCESS;
+ goto out;
+ }
+ }
goto another_round;
case RX_HANDLER_EXACT:
deliver_exact = true;
--
2.20.1
