bnxt_en: Add XDP RSS hash metadata support [LWN.net]

From:		Chris J Arges <carges-AT-cloudflare.com>
To:		netdev-AT-vger.kernel.org, michael.chan-AT-broadcom.com, pavan.chebbi-AT-broadcom.com, davem-AT-davemloft.net, joe-AT-dama.to, gospo-AT-broadcom.com, kuba-AT-kernel.org, pabeni-AT-redhat.com, edumazet-AT-google.com
Subject:		[PATCH net-next v5 0/6] bnxt_en: Add XDP RSS hash metadata support
Date:		Wed, 25 Mar 2026 15:09:46 -0500
Message-ID:		<20260325201139.2501937-1-carges@cloudflare.com>
Cc:		andrew+netdev-AT-lunn.ch, horms-AT-kernel.org, ast-AT-kernel.org, daniel-AT-iogearbox.net, hawk-AT-kernel.org, john.fastabend-AT-gmail.com, sdf-AT-fomichev.me, shuah-AT-kernel.org, bpf-AT-vger.kernel.org, linux-kselftest-AT-vger.kernel.org, kernel-team-AT-cloudflare.com, Chris J Arges <carges-AT-cloudflare.com>
Archive-link:		Article

This series adds XDP RSS hash metadata extraction support for the bnxt_en
driver and includes selftests to validate the functionality. I was able
to test this on a BCM57414 NIC.

Patches 1-4 implement the driver support:
  - Patch 1 adds bnxt_xdp_buff to wrap xdp_buff with
    pointers to the hardware RX completion descriptors and the
    completion type. This is similar to other driver implementations.
  - Patch 2 adds xmo_rx_hash callback for CMP_TYPE_RX_L2_CMP completions.
  - Patch 3 moves bnxt_rss_ext_op to bnxt.h
  - Patch 4 adds handling for CMP_TYPE_RX_L2_V3_CMP completions

Patches 5-6 add selftest coverage:
  - Patch 5 refactors common BPF map helper functions out of the
    existing xdp.py selftest into a shared net/lib/py/bpf.py module.
  - Patch 6 adds an XDP metadata selftest that loads an XDP program
    calling bpf_xdp_metadata_rx_hash. The test skips on devices without
    xdp-rx-metadata-features.

Changes from v4: https://lore.kernel.org/all/20260313223029.454755-1-carge...
  - address RCT again
  - make _format_hex_bytes private
  - remove redundant bpf_map_set
  - rebased on net-next

Changes from v3: https://lore.kernel.org/netdev/20260306230600.1628196-1-c...
  - split out bnxt_rss_ext_op into header
  - address RCT issue
  - rebased on net-next

Changes from v2: https://lore.kernel.org/netdev/20260303024510.644962-1-ca...
  - bnxt xdp: actually fixed RCT issues
  - bnxt xdp: Added patch 3 to handle CMP_TYPE_RX_L2_V3_CMP completions.

Changes from v1: https://lore.kernel.org/netdev/cover.1772211065.git.carge...
  - selftests: moved tests into net/hw
  - selftests: fix pylinter errors
  - selftests: add check for no error count
  - bnxt_xdp: followed RCT for variable declaration
  - rebased on net-next

Chris J Arges (6):
  bnxt_en: use bnxt_xdp_buff for xdp context
  bnxt_en: Implement XDP RSS hash metadata extraction
  bnxt_en: Move bnxt_rss_ext_op into header
  bnxt_en: Implement XDP RSS hash metadata extraction for V3_CMP
  selftests: net: move common xdp.py functions into lib
  selftests: drv-net: xdp: Add rss_hash metadata tests

 drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  51 +++---
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |  19 ++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |  57 ++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h |  10 ++
 .../testing/selftests/drivers/net/hw/Makefile |   1 +
 .../drivers/net/hw/lib/py/__init__.py         |   2 +
 .../selftests/drivers/net/hw/xdp_metadata.py  | 146 ++++++++++++++++
 .../selftests/drivers/net/lib/py/__init__.py  |   2 +
 tools/testing/selftests/drivers/net/xdp.py    |  96 +++--------
 .../testing/selftests/net/lib/py/__init__.py  |   2 +
 tools/testing/selftests/net/lib/py/bpf.py     |  68 ++++++++
 .../selftests/net/lib/xdp_metadata.bpf.c      | 163 ++++++++++++++++++
 12 files changed, 516 insertions(+), 101 deletions(-)
 create mode 100644 tools/testing/selftests/drivers/net/hw/xdp_metadata.py
 create mode 100644 tools/testing/selftests/net/lib/py/bpf.py
 create mode 100644 tools/testing/selftests/net/lib/xdp_metadata.bpf.c

-- 
2.43.0