[RFC PATCH bpf-next v1 6/7] veth: support the rx_csum XDP metadata hint
From: Vladimir Vdovin <hidden>
Date: 2026-06-30 19:18:09
Also in:
bpf
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Implement xmo_rx_csum from skb->ip_summed. veth has no real hardware; this surfaces whatever checksum verdict the skb already carries and makes the metadata kfunc testable without a NIC. Signed-off-by: Vladimir Vdovin <redacted> --- drivers/net/veth.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 1c5142149175..b7bc5a3b07e5 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c@@ -1700,6 +1700,28 @@ static int veth_xdp_rx_vlan_tag(const struct xdp_md *ctx, __be16 *vlan_proto, return err; } +static int veth_xdp_rx_csum(const struct xdp_md *ctx, + enum xdp_csum_status *csum_status) +{ + const struct veth_xdp_buff *_ctx = (void *)ctx; + const struct sk_buff *skb = _ctx->skb; + + if (!skb) + return -ENODATA; + + /* veth has no real hardware; surface whatever checksum verdict the + * skb already carries (e.g. CHECKSUM_PARTIAL/UNNECESSARY from a local + * sender or a previous validation). + */ + if (skb->ip_summed == CHECKSUM_UNNECESSARY || + skb->ip_summed == CHECKSUM_PARTIAL) + *csum_status = XDP_CSUM_VERIFIED; + else + *csum_status = XDP_CSUM_NONE; + + return 0; +} + static const struct net_device_ops veth_netdev_ops = { .ndo_init = veth_dev_init, .ndo_open = veth_open,
@@ -1725,6 +1747,7 @@ static const struct xdp_metadata_ops veth_xdp_metadata_ops = { .xmo_rx_timestamp = veth_xdp_rx_timestamp, .xmo_rx_hash = veth_xdp_rx_hash, .xmo_rx_vlan_tag = veth_xdp_rx_vlan_tag, + .xmo_rx_csum = veth_xdp_rx_csum, }; #define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \
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2.47.0