Re: [PATCH bpf-next v7 3/3] selftests/bpf: add testcase for TRACING with 6+ arguments

[Daniel Borkmann <daniel@iogearbox.net>]

On 6/22/23 9:57 AM, menglong8.dong@gmail.com wrote:
> From: Menglong Dong <imagedong@tencent.com>

(CC'ing also Florent wrt arm64)

> Add test9/test10 in fexit_test.c and fentry_test.c to test the fentry
> and fexit whose target function have 7/11 arguments.
> 
> Correspondingly, add bpf_testmod_fentry_test7() and
> bpf_testmod_fentry_test11() to bpf_testmod.c
> 
> Meanwhile, add bpf_modify_return_test2() to test_run.c to test the
> MODIFY_RETURN with 7 arguments.
> 
> Add bpf_testmod_test_struct_arg_7/bpf_testmod_test_struct_arg_7 in
> bpf_testmod.c to test the struct in the arguments.
> 
> And the testcases passed:
> 
> ./test_progs -t fexit
> Summary: 5/12 PASSED, 0 SKIPPED, 0 FAILED
> 
> ./test_progs -t fentry
> Summary: 3/0 PASSED, 0 SKIPPED, 0 FAILED
> 
> ./test_progs -t modify_return
> Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
> 
> ./test_progs -t tracing_struct
> Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
> 
> Signed-off-by: Menglong Dong <imagedong@tencent.com>
> Acked-by: Yonghong Song <yhs@fb.com>
> ---
> v6:
> - add testcases to tracing_struct.c instead of fentry_test.c and
>    fexit_test.c
> v5:
> - add testcases for MODIFY_RETURN
> v4:
> - use different type for args in bpf_testmod_fentry_test{7,12}
> - add testcase for grabage values in ctx
> v3:
> - move bpf_fentry_test{7,12} to bpf_testmod.c and rename them to
>    bpf_testmod_fentry_test{7,12} meanwhile
> - get return value by bpf_get_func_ret() in
>    "fexit/bpf_testmod_fentry_test12", as we don't change ___bpf_ctx_cast()
>    in this version
> ---
>   net/bpf/test_run.c                            | 23 ++++++--
>   .../selftests/bpf/bpf_testmod/bpf_testmod.c   | 49 ++++++++++++++++-
>   .../selftests/bpf/prog_tests/fentry_fexit.c   |  4 +-
>   .../selftests/bpf/prog_tests/fentry_test.c    |  2 +
>   .../selftests/bpf/prog_tests/fexit_test.c     |  2 +
>   .../selftests/bpf/prog_tests/modify_return.c  | 20 ++++++-
>   .../selftests/bpf/prog_tests/tracing_struct.c | 19 +++++++
>   .../testing/selftests/bpf/progs/fentry_test.c | 32 +++++++++++
>   .../testing/selftests/bpf/progs/fexit_test.c  | 33 ++++++++++++
>   .../selftests/bpf/progs/modify_return.c       | 40 ++++++++++++++
>   .../selftests/bpf/progs/tracing_struct.c      | 54 +++++++++++++++++++
>   11 files changed, 271 insertions(+), 7 deletions(-)

This triggers test failures on arm64 in BPF CI given the additions are
not yet supported there:

https://github.com/kernel-patches/bpf/actions/runs/5371020820/jobs/9743606263
https://github.com/kernel-patches/bpf/actions/runs/5371020820/jobs/9743606326

[...]
Notice: Success: 362/3077, Skipped: 12, Failed: 3
Error: #71 fentry_fexit
   Error: #71 fentry_fexit
   test_fentry_fexit:PASS:fentry_skel_load 0 nsec
   test_fentry_fexit:PASS:fexit_skel_load 0 nsec
   test_fentry_fexit:FAIL:fentry_attach unexpected error: -1 (errno 524)
Error: #72 fentry_test
   Error: #72 fentry_test
   test_fentry_test:PASS:fentry_skel_load 0 nsec
   fentry_test:FAIL:fentry_attach unexpected error: -1 (errno 524)
   test_fentry_test:FAIL:fentry_first_attach unexpected error: -1 (errno 524)
Error: #76 fexit_test
   Error: #76 fexit_test
   test_fexit_test:PASS:fexit_skel_load 0 nsec
   fexit_test:FAIL:fexit_attach unexpected error: -1 (errno 524)
   test_fexit_test:FAIL:fexit_first_attach unexpected error: -1 (errno 524)
[...]

I think probably the best way would be to separate the new test cases and
then update tools/testing/selftests/bpf/DENYLIST.aarch64 to exclude them
from being run on arm64 until support gets added there too.

Thanks,
Daniel