Re: [PATCH bpf 0/3] xsk: require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len

[Maciej Fijalkowski <maciej.fijalkowski@intel.com>]

On Fri, Jul 12, 2024 at 06:52:50PM -0700, Stanislav Fomichev wrote:
> Julian reports that commit 341ac980eab9 ("xsk: Support tx_metadata_len")
> can break existing use cases which don't zero-initialize xdp_umem_reg
> padding. Fix it (while still breaking a minority of new users of tx
> metadata), update the docs, update the selftest and sprinkle some
> BUILD_BUG_ONs to hopefully catch similar issues in the future.
> 
> Thank you Julian for the report and for helping to chase it down!
> 
> Reported-by: Julian Schindel <mail@arctic-alpaca.de>
> Cc: Magnus Karlsson <magnus.karlsson@gmail.com>

For the content series,

Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>

However I was not sure about handling patch 3/3.

Thanks!

> 
> Stanislav Fomichev (3):
>   xsk: require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len
>   selftests/bpf: Add XDP_UMEM_TX_METADATA_LEN to XSK TX metadata test
>   xsk: Try to make xdp_umem_reg extension a bit more future-proof
> 
>  Documentation/networking/xsk-tx-metadata.rst  | 16 ++++++++-----
>  include/uapi/linux/if_xdp.h                   |  4 ++++
>  net/xdp/xdp_umem.c                            |  9 +++++---
>  net/xdp/xsk.c                                 | 23 ++++++++++---------
>  tools/include/uapi/linux/if_xdp.h             |  4 ++++
>  .../selftests/bpf/prog_tests/xdp_metadata.c   |  3 ++-
>  6 files changed, 38 insertions(+), 21 deletions(-)
> 
> -- 
> 2.45.2
> 
>