Commit 6d9b7c85af57 for kernel

commit 6d9b7c85af57305ec2bd5907124478867edcc60b
Author: Lorenzo Bianconi <lorenzo.bianconi@oss.qualcomm.com>
Date:   Mon Nov 2 12:46:04 2026 +0100

    net: stmmac: set XDP metadata length on the page_pool RX path

    stmmac_rx() initializes the XDP buffer with the metadata area valid, so
    an XDP program can reserve metadata with bpf_xdp_adjust_meta() and write
    it in [xdp->data_meta, xdp->data), for example to export the RX hardware
    timestamp obtained from the metadata kfunc. When such a frame is passed
    to the stack, the skb is built in place around the same page with
    napi_build_skb(), but skb_metadata_set() is never called.

    napi_build_skb() clears skb_shared_info up to dataref, which includes
    meta_len, so skb_metadata_len() stays zero. The stack and TC BPF then see
    an empty metadata range even though the bytes are present in the skb
    headroom. The AF_XDP zero-copy path already records the length in
    stmmac_construct_skb_zc().

    Record the metadata length after reserving the headroom and adding the
    frame data. No copy is needed because the skb is built over the buffer the
    XDP program wrote to. With the length recorded, the software VLAN
    stripping path can move the metadata together with the MAC header, as it
    already does for zero-copy frames.

    Fixes: e3f9c3e34840 ("net: stmmac: add Rx HWTS metadata to XDP receive pkt")
    Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@oss.qualcomm.com>
    Reviewed-by: Daniel Machon <daniel.machon@microchip.com>
    Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de>
    Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
    Link: https://patch.msgid.link/20261102-stmmac_meatada_pp_path-v1-1-d93cc4f9a864@oss.qualcomm.com
    Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 7ffed295eb14..a2177777727e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -6017,7 +6017,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 		}

 		if (!skb) {
-			unsigned int head_pad_len;
+			unsigned int metasize;

 			/* XDP program may expand or reduce tail */
 			buf1_len = ctx.xdp.data_end - ctx.xdp.data;
@@ -6034,10 +6034,14 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 			}

 			/* XDP program may adjust header */
-			head_pad_len = ctx.xdp.data - ctx.xdp.data_hard_start;
-			skb_reserve(skb, head_pad_len);
+			skb_reserve(skb,
+				    ctx.xdp.data - ctx.xdp.data_hard_start);
 			skb_put(skb, buf1_len);
 			skb_mark_for_recycle(skb);
+
+			metasize = ctx.xdp.data - ctx.xdp.data_meta;
+			if (metasize)
+				skb_metadata_set(skb, metasize);
 			buf->page = NULL;
 		} else if (buf1_len) {
 			dma_sync_single_for_cpu(priv->device, buf->addr,