Re: [PATCH bpf-next] selftests/bpf: make libbpf_probe_prog_types testcase aware of kernel configuration

[Artem Savkov]

On Fri, Sep 30, 2022 at 04:06:41PM -0700, Andrii Nakryiko wrote:
> On Fri, Sep 30, 2022 at 4:09 AM Artem Savkov <asavkov@xxxxxxxxxx> wrote:
> >
> > At the moment libbpf_probe_prog_types test iterates over all available
> > BPF_PROG_TYPE regardless of kernel configuration which can exclude some
> > of those. Unfortunately there is no direct way to tell which types are
> > available, but we can look at struct bpf_ctx_onvert to tell which ones
> > are available.
> >
> > Signed-off-by: Artem Savkov <asavkov@xxxxxxxxxx>
> > ---
> 
> Many selftests assume correct kernel configuration which is encoded in
> config and config.<arch> files. So it seems fair to assume that all
> defined program types are available on kernel-under-test.

Ok. Wasn't sure if this is the assumption being made.

> If someone is running selftests under custom more minimal kernel they
> can use denylist to ignore specific prog type subtests?

Thanks for the suggestion. Denylist is a bit too broad in this case as
it means we'll be disabling the whole libbpf_probe_prog_types test while
only a single type is a problem. Looks like we'll have to live with a
downstream-only patch in this case.

-- 
 Artem