[PATCH net] eth: fbnic: Report the logical RX queue to XDP

[PATCH net] eth: fbnic: Report the logical RX queue to XDP

[Björn Töpel]

fbnic reports queue 0 to XDP on all RX queues. The XDP RX queue is
registered with the header buffer queue index, which is always 0,
instead of the completion queue index, which is the netdev queue id.

Any XDP program that reads rx_queue_index gets 0 on every queue, so a
program that uses the queue id uses the wrong queue. AF_XDP has the
same problem: XSKMAP finds the wrong socket, and redirect to a socket
on another queue fails.

Triggered on fbnic hardware (50G, firmware 25.08.05-004) with AF_XDP
zero-copy: sockets on queues other than 0 got no packets. With this
fix, a socket on queue 43, and sockets on four queues at once, get
their packets. On the QEMU model with two queues, a kprobe shows 0 and
0 before the fix, and 0 and 1 after it.

Fixes: 894d4a4ea6cb ("eth: fbnic: move xdp_rxq_info_reg() to resource alloc")
Signed-off-by: Björn Töpel <bjorn@kernel.org>
---
 drivers/net/ethernet/meta/fbnic/fbnic_txrx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
index c572a0062e77..0bcee152d47c 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
@@ -2072,7 +2072,7 @@ static int fbnic_alloc_rx_qt_resources(struct fbnic_net *fbn,
 
 	fbnic_bdq_set_page_size(&qt->sub1, rx_page_size);
 
-	err = xdp_rxq_info_reg(&qt->xdp_rxq, fbn->netdev, qt->sub0.q_idx,
+	err = xdp_rxq_info_reg(&qt->xdp_rxq, fbn->netdev, qt->cmpl.q_idx,
 			       nv->napi.napi_id);
 	if (err)
 		goto free_page_pools;

base-commit: d8a4f4c59da52b7c31ae337243b8473a19a3f819
-- 
2.56.0