> diff --git a/tools/testing/selftests/bpf/prog_tests/prog_run_opts.c
> b/tools/testing/selftests/bpf/prog_tests/prog_run_opts.c
> index 01f1d1b6715a..9cc898e6a9f7 100644
> --- a/tools/testing/selftests/bpf/prog_tests/prog_run_opts.c
> +++ b/tools/testing/selftests/bpf/prog_tests/prog_run_opts.c
> @@ -4,6 +4,10 @@
>
> #include "test_pkt_access.skel.h"
>
> +#define NONLINEAR_PKT_LEN 9000
> +#define NONLINEAR_LINEAR_DATA_LEN 64
> +#define SHORT_OUT_LEN 100
> +
[ ... ]
> @@ -20,6 +24,69 @@ static void check_run_cnt(int prog_fd, __u64 run_cnt)
> "incorrect number of repetitions, want %llu have %llu\n",
> run_cnt, info.run_cnt);
> }
>
> +static void init_pkt(__u8 *pkt, size_t len)
> +{
> + size_t i;
> +
> + for (i = 0; i < len; i++)
> + pkt[i] = i & 0xff;
> +}
A question was raised on v2 about whether pkt_v4 could be reused by
reducing the linear area to ETH_HLEN, rather than introducing a custom
init_pkt() with a 9000-byte stack packet.
Can't we reuse pkt_v4 here by reducing the linear area to ETH_HLEN?
The v3 still adds init_pkt() and the NONLINEAR_PKT_LEN packet, so this
doesn't seem to have been picked up.
> +
> +static void test_skb_nonlinear_data_out_partial(struct test_pkt_access *skel)
> +{
> + LIBBPF_OPTS(bpf_test_run_opts, topts);
> + __u8 pkt[NONLINEAR_PKT_LEN];
> + __u8 out[SHORT_OUT_LEN];
> + struct __sk_buff skb = {};
> + int prog_fd, err;
> +
> + init_pkt(pkt, sizeof(pkt));
> +
> + skb.data_end = NONLINEAR_LINEAR_DATA_LEN;
> +
> + topts.data_in = pkt;
> + topts.data_size_in = sizeof(pkt);
> + topts.data_out = out;
> + topts.data_size_out = sizeof(out);
> + topts.ctx_in = &skb;
> + topts.ctx_size_in = sizeof(skb);
> +
> + prog_fd = bpf_program__fd(skel->progs.tc_pass_prog);
[ ... ]
> diff --git a/tools/testing/selftests/bpf/progs/test_pkt_access.c
> b/tools/testing/selftests/bpf/progs/test_pkt_access.c
> index bce7173152c6..cd284401eebd 100644
> --- a/tools/testing/selftests/bpf/progs/test_pkt_access.c
> +++ b/tools/testing/selftests/bpf/progs/test_pkt_access.c
> @@ -150,3 +150,15 @@ int test_pkt_access(struct __sk_buff *skb)
>
> return TC_ACT_UNSPEC;
> }
> +
> +SEC("tc")
> +int tc_pass_prog(struct __sk_buff *skb)
> +{
> + return TC_ACT_OK;
> +}
> +
> +SEC("xdp.frags")
> +int xdp_frags_pass_prog(struct xdp_md *ctx)
> +{
> + return XDP_PASS;
> +}
A related suggestion on v2 was that, once pkt_v4 is reused, the existing
BPF program could be reused instead of adding new pass-through programs.
Could tc_pass_prog and xdp_frags_pass_prog be dropped in favour of the
existing program? The v3 still adds both of these, so this point also
seems to be open.
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/27680511802
