github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-11-07 06:17:02 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

net: lan966x: fix the DB dataptr of frames from ndo_xdp_xmit

Browse Source 
lan966x_fdma_xmit_xdpf() transmits both XDP_TX frames and xdp_frames
from ndo_xdp_xmit, and builds the DB with
lan966x_fdma_xdp_tx_dataptr_cb(), which adds XDP_PACKET_HEADROOM to the
stored DMA address.

Before this patch, the headroom is also added for xdp_frames. For
XDP_TX the stored address is the start of the page pool page, but for an
xdp_frame it is the mapping of the IFH placed in front of the frame
data, so frames from ndo_xdp_xmit are read from XDP_PACKET_HEADROOM
bytes after their IFH.

Use the plain tx dataptr callback for xdp_frames.

Found by an AI code review agent. Reproduced on a lan9668 board with an
XDP program redirecting frames from one port to another: none of the 20
frames arrived intact on the link partner. With the fix all 20 did.

Fixes: 29cc3a66a8 ("net: lan966x: use FDMA library for adding DCB's in the tx path")
Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://patch.msgid.link/20261026-lan966x-xdp-xmit-dataptr-v1-1-d0dd068324de@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Daniel Machon 2026-10-26 14:46:39 +01:00 committed by Jakub Kicinski
parent 2cffcf1aea
commit ce3192e0da
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
View File

@ -686,7 +686,8 @@ int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, void *ptr, u32 len)
FDMA_DCB_STATUS_BLOCKO(0) |
FDMA_DCB_STATUS_BLOCKL(next_dcb_buf->len),
&fdma_nextptr_cb,
&lan966x_fdma_xdp_tx_dataptr_cb);
len ? &lan966x_fdma_xdp_tx_dataptr_cb :
&lan966x_fdma_tx_dataptr_cb);
/* Start the transmission */
lan966x_fdma_tx_start(tx);