Re: [PATCH bpf-next 2/2] selftests: bpf: Add a new test for bare tracepoints

From: Qais Yousef
Date: Wed Jan 13 2021 - 05:22:39 EST


On 01/12/21 12:07, Andrii Nakryiko wrote:
> > > > $ sudo ./test_progs -v -t module_attach
> > >
> > > use -vv when debugging stuff like that with test_progs, it will output
> > > libbpf detailed logs, that often are very helpful
> >
> > I tried that but it didn't help me. Full output is here
> >
> > https://paste.debian.net/1180846
> >
>
> It did help a bit for me to make sure that you have bpf_testmod
> properly loaded and its BTF was found, so the problem is somewhere
> else. Also, given load succeeded and attach failed with OPNOTSUPP, I
> suspect you are missing some of FTRACE configs, which seems to be
> missing from selftests's config as well. Check that you have
> CONFIG_FTRACE=y and CONFIG_DYNAMIC_FTRACE=y, and you might need some
> more. See [0] for a real config we are using to run all tests in
> libbpf CI. If you figure out what you were missing, please also
> contribute a patch to selftests' config.
>
> [0] https://github.com/libbpf/libbpf/blob/master/travis-ci/vmtest/configs/latest.config

Yeah that occurred to me too. I do have all necessary FTRACE options enabled,
including DYNAMIC_FTRACE. I think I did try enabling fault injection too just
in case. I have CONFIG_FAULT_INJECTION=y and CONFIG_FUNCTION_ERROR_INJECTION=y.

I will look at the CI config and see if I can figure it out.

I will likely get a chance to look at all of this and send v2 over the
weekend.

Thanks

--
Qais Yousef