From e4e9baf06a6ea6cfbf69db4c3766a0879329dda2 Mon Sep 17 00:00:00 2001 From: Magnus Karlsson Date: Wed, 22 Sep 2021 09:56:12 +0200 Subject: [PATCH] selftests: xsk: Change interleaving of packets in unaligned mode Change the interleaving of packets in unaligned mode. With the current buffer addresses in the packet stream, the last buffer in the umem could not be used as a large packet could potentially write over the end of the umem. The kernel correctly threw this buffer address away and refused to use it. This is perfectly fine for all regular packet streams, but the ones used for unaligned mode have every other packet being at some different offset. As we will add checks for correct offsets in the next patch, this needs to be fixed. Just start these page-boundary straddling buffers one page earlier so that the last one is not on the last page of the umem, making all buffers valid. Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210922075613.12186-13-magnus.karlsson@gmail.com --- tools/testing/selftests/bpf/xdpxceiver.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c index 3beea7531c8e9..fd620f8accfd3 100644 --- a/tools/testing/selftests/bpf/xdpxceiver.c +++ b/tools/testing/selftests/bpf/xdpxceiver.c @@ -543,14 +543,14 @@ static void pkt_stream_replace(struct test_spec *test, u32 nb_pkts, u32 pkt_len) test->ifobj_rx->pkt_stream = pkt_stream; } -static void pkt_stream_replace_half(struct test_spec *test, u32 pkt_len, u32 offset) +static void pkt_stream_replace_half(struct test_spec *test, u32 pkt_len, int offset) { struct xsk_umem_info *umem = test->ifobj_tx->umem; struct pkt_stream *pkt_stream; u32 i; pkt_stream = pkt_stream_clone(umem, test->pkt_stream_default); - for (i = 0; i < test->pkt_stream_default->nb_pkts; i += 2) { + for (i = 1; i < test->pkt_stream_default->nb_pkts; i += 2) { pkt_stream->pkts[i].addr = (i % umem->num_frames) * umem->frame_size + offset; pkt_stream->pkts[i].len = pkt_len; } @@ -1209,7 +1209,7 @@ static bool testapp_unaligned(struct test_spec *test) test->ifobj_tx->umem->unaligned_mode = true; test->ifobj_rx->umem->unaligned_mode = true; /* Let half of the packets straddle a buffer boundrary */ - pkt_stream_replace_half(test, PKT_SIZE, test->ifobj_tx->umem->frame_size - 32); + pkt_stream_replace_half(test, PKT_SIZE, -PKT_SIZE / 2); test->ifobj_rx->pkt_stream->use_addr_for_fill = true; testapp_validate_traffic(test);