Re: [PATCH v5 00/11] bpf: introduce extensible load API

[Stephen Hemminger <stephen@networkplumber.org>]

On Fri, 12 Jun 2026 09:42:07 +0100
Marat Khalili <marat.khalili@huawei.com> wrote:

> This patchset introduces an extensible load API for the BPF library in
> DPDK, addressing current limitations regarding ABI stability and feature
> constraints.
> 
> Currently, `rte_bpf_load` relies on a fixed `struct rte_bpf_prm`, which
> makes it difficult to add new loading options or parameters without
> breaking the ABI.
> 
> To resolve these issues, this series introduces `rte_bpf_load_ex` taking
> `struct rte_bpf_prm_ex`. The new parameter structure includes a `sz`
> field for backward compatibility, allowing future extensions.
> 
> Taking advantage of the new extensible API, this patchset also adds
> several new features:
> * Support for loading and executing BPF programs with up to 5 arguments.
> * Support for loading classic BPF (cBPF) directly.
> * Support for loading ELF files directly from memory buffers.
> * New API functions (`rte_bpf_eth_rx_install` and `rte_bpf_eth_tx_install`)
>   to install an already loaded BPF program as a port callback, decoupling
>   the loading phase from the installation phase.
> 
> 
> v5:
> * Fixed compilation between commits broken in v4 while addressing AI
>   comments.
> * Rebased on fresh main, addressing conflicts in release notes.
> 
> v4:
> * Restored missing NULL checks in wrapper functions `rte_bpf_load` and
>   `rte_bpf_elf_load`.
> * Fixed the burst execution functions (`rte_bpf_exec_burst*`) to return
>   `0` and set `rte_errno = EINVAL` on failure, preventing `-EINVAL`
>   being reinterpreted as a large `uint32_t` value. Initialized `rc`
>   properly in scalar execution wrappers for this case.
> * Swapped the Doxygen comments in `rte_bpf_ethdev.h` for RX and TX functions.
> * Added diagnostic dump on failure path in `test_bpf_filter`.
> * Fixed memory leak of the BPF handle in `bpf_rx_test` upon install failure.
> * Added tests for NULL parameter rejection, mismatched execution arguments,
>   unsupported execution flags, and the libpcap-less `rte_bpf_convert` stub.
> 
> v3:
> * Appended Acked-by tags to all individual commits to align with
>   patchwork requirements.
> 
> v2:
> * Fixed a potential segmentation fault in `exec_vm_burst_ex` by deferring
>   the dereference of `ctx[i].arg` until it is confirmed that `nb_prog_arg > 0`.
> * Clarified documentation and code comments for `RTE_BPF_EXEC_FLAG_JIT`
>   requirements and fast-path expectations.
> 
> 
> Marat Khalili (11):
>   bpf: make logging prefixes more consistent
>   bpf: introduce extensible load API
>   bpf: support up to 5 arguments
>   bpf: add cBPF origin to rte_bpf_load_ex
>   bpf: support rte_bpf_prm_ex with port callbacks
>   bpf: support loading ELF files from memory
>   test/bpf: test loading cBPF directly
>   test/bpf: test loading ELF file from memory
>   doc: add release notes for new extensible BPF API
>   doc: add load API to BPF programmer's guide
>   test/bpf: add tests for error handling contracts
> 
>  app/test/test_bpf.c                    | 455 +++++++++++++++++--------
>  doc/guides/prog_guide/bpf_lib.rst      |  75 +++-
>  doc/guides/rel_notes/release_26_07.rst |  20 ++
>  lib/bpf/bpf.c                          |  32 +-
>  lib/bpf/bpf_convert.c                  |  99 +++++-
>  lib/bpf/bpf_exec.c                     | 134 +++++++-
>  lib/bpf/bpf_impl.h                     |  53 ++-
>  lib/bpf/bpf_jit_arm64.c                |  18 +-
>  lib/bpf/bpf_jit_x86.c                  |  10 +-
>  lib/bpf/bpf_load.c                     | 213 ++++++++++--
>  lib/bpf/bpf_load_elf.c                 | 189 ++++++----
>  lib/bpf/bpf_pkt.c                      |  65 +++-
>  lib/bpf/bpf_stub.c                     |  46 ---
>  lib/bpf/bpf_validate.c                 |  94 +++--
>  lib/bpf/meson.build                    |  15 +-
>  lib/bpf/rte_bpf.h                      | 199 ++++++++++-
>  lib/bpf/rte_bpf_ethdev.h               |  54 +++
>  17 files changed, 1400 insertions(+), 371 deletions(-)
>  delete mode 100644 lib/bpf/bpf_stub.c
> 

Detailed AI review found some minor things:

02/11: comment grammar nits — "Any features that not known to
the application" -> "that are not known" (twice); "the size of
same struct" -> "the size of the same struct".

05/11: Doxygen for rte_bpf_eth_rx_install and
rte_bpf_eth_tx_install references rte_bpf_eth_unload, which does
not exist. Use rte_bpf_eth_rx_unload and rte_bpf_eth_tx_unload
respectively.

07/11: stray space before comma in the test_bpf_filter log
string ("for \"%s\" ,").