On Tue, Jul 28, 2020 at 5:14 AM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote:
>
> s390 uses socketcall multiplexer instead of individual socket syscalls.
> Therefore, "kprobe/" SYSCALL(sys_connect) does not trigger and
> test_map_in_map fails. Fix by using "kprobe/__sys_connect" instead.
samples/bpf is in semi-deprecated state. I tried for quite some time, but still
cannot build it all successfully. So I apologize for bounding the
question to you...
>From the code, we do the SYSCALL() trick to change the exact name for
different architecture. Would this change break the same file for x86?
Thanks,
Song
>
> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
> ---
> samples/bpf/test_map_in_map_kern.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/samples/bpf/test_map_in_map_kern.c b/samples/bpf/test_map_in_map_kern.c
> index 8def45c5b697..b0200c8eac09 100644
> --- a/samples/bpf/test_map_in_map_kern.c
> +++ b/samples/bpf/test_map_in_map_kern.c
> @@ -103,10 +103,9 @@ static __always_inline int do_inline_hash_lookup(void *inner_map, u32 port)
> return result ? *result : -ENOENT;
> }
>
> -SEC("kprobe/" SYSCALL(sys_connect))
> +SEC("kprobe/__sys_connect")
> int trace_sys_connect(struct pt_regs *ctx)
> {
> - struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1_CORE(ctx);
> struct sockaddr_in6 *in6;
> u16 test_case, port, dst6[8];
> int addrlen, ret, inline_ret, ret_key = 0;
> @@ -114,8 +113,8 @@ int trace_sys_connect(struct pt_regs *ctx)
> void *outer_map, *inner_map;
> bool inline_hash = false;
>
> - in6 = (struct sockaddr_in6 *)PT_REGS_PARM2_CORE(real_regs);
> - addrlen = (int)PT_REGS_PARM3_CORE(real_regs);
> + in6 = (struct sockaddr_in6 *)PT_REGS_PARM2_CORE(ctx);
> + addrlen = (int)PT_REGS_PARM3_CORE(ctx);
>
> if (addrlen != sizeof(*in6))
> return 0;
> --
> 2.25.4
>
