Re: [PATCH bpf-next v7 0/9] Introduce arena library and runtime

Kumar Kartikeya Dwivedi
2026-04-12T19:23:31Z

On Sun, 12 Apr 2026 at 19:45, Emil Tsalapatis <emil@etsalapatis.com> wrote:
>
> Add a new subdirectory to tools/testing/selftests/bpf called libarena,
> along with programs useful for writing arena-based BPF code. This
> patchset adds the following:
>
> 1) libarena, a subdirectory where arena BPF code that is generally useful
> to BPF arena programs can be easily added and tested.
>
> 2) An ASAN runtime for BPF arena programs. BPF arenas allow for accessing
> memory after it has been freed or if it is out of bounds, making it more
> difficult to triage bugs combined to regular BPF. Use LLVM's recently added
> support for address-space based sanitization to selectively sanitize just
> the arena accesses.
>
> 3) A buddy memory allocator that can be reused by BPF programs to handle
> memory allocation/deletion. The allocator uses the ASAN runtime to add
> address sanitization if requested.
>
> The patch includes testing for the new allocators and ASAN features that
> can be built from the top directory using "make libarena_test" and
> "make libarena_test_asan". The generated binaries reside in libarena/.
> The patch also adds test-progs-based selftests to the codebase for the
> libarena code, so the new tests are run by ./test_progs.
>

I am back in the same position as I was with comments in [0].

I.e., again, I don't see anything in the stream output (passing -v to
test_libarena_asan) when I build it with clang 23 (LLVM tip).
What am I doing wrong? (Leaving aside all feedback about integrating
it in the regular test runner that is still unaddressed, thus tests do
not run by default).

[0]: https://lore.kernel.org/bpf/CAP01T75+BoQfQN=47NhYYviZttjCPb_CXNpa=DUC0=xSvdNZdA@mail.gmail.com

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