This is a note to let you know that I've just added the patch titled samples/bpf: Fix to xdpsock to avoid recycling frames to the 5.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: samples-bpf-fix-to-xdpsock-to-avoid-recycling-frames.patch and it can be found in the queue-5.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2fd78b6374825d97d03c6b1e0036be0198d0a761 Author: Weqaar Janjua <weqaar.a.janjua@xxxxxxxxx> Date: Sat Aug 29 00:17:17 2020 +0800 samples/bpf: Fix to xdpsock to avoid recycling frames [ Upstream commit b69e56cf765155dcac0037d7d0f162a2afab76c2 ] The txpush program in the xdpsock sample application is supposed to send out all packets in the umem in a round-robin fashion. The problem is that it only cycled through the first BATCH_SIZE worth of packets. Fixed this so that it cycles through all buffers in the umem as intended. Fixes: 248c7f9c0e21 ("samples/bpf: convert xdpsock to use libbpf for AF_XDP access") Signed-off-by: Weqaar Janjua <weqaar.a.janjua@xxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Acked-by: Björn Töpel <bjorn.topel@xxxxxxxxx> Link: https://lore.kernel.org/bpf/20200828161717.42705-1-weqaar.a.janjua@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c index c91e91362a0c6..0151bb0b2fc71 100644 --- a/samples/bpf/xdpsock_user.c +++ b/samples/bpf/xdpsock_user.c @@ -921,7 +921,7 @@ static void rx_drop_all(void) } } -static void tx_only(struct xsk_socket_info *xsk, u32 frame_nb, int batch_size) +static void tx_only(struct xsk_socket_info *xsk, u32 *frame_nb, int batch_size) { u32 idx; unsigned int i; @@ -934,14 +934,14 @@ static void tx_only(struct xsk_socket_info *xsk, u32 frame_nb, int batch_size) for (i = 0; i < batch_size; i++) { struct xdp_desc *tx_desc = xsk_ring_prod__tx_desc(&xsk->tx, idx + i); - tx_desc->addr = (frame_nb + i) << XSK_UMEM__DEFAULT_FRAME_SHIFT; + tx_desc->addr = (*frame_nb + i) << XSK_UMEM__DEFAULT_FRAME_SHIFT; tx_desc->len = PKT_SIZE; } xsk_ring_prod__submit(&xsk->tx, batch_size); xsk->outstanding_tx += batch_size; - frame_nb += batch_size; - frame_nb %= NUM_FRAMES; + *frame_nb += batch_size; + *frame_nb %= NUM_FRAMES; complete_tx_only(xsk, batch_size); } @@ -997,7 +997,7 @@ static void tx_only_all(void) } for (i = 0; i < num_socks; i++) - tx_only(xsks[i], frame_nb[i], batch_size); + tx_only(xsks[i], &frame_nb[i], batch_size); pkt_cnt += batch_size;