> As part of the effort to limit undefined behaviors in DPDK code, some
> structure alignments revealed not to be accurate enough.
> At the moment two structures have been identified but others may be
> found while running more parts of DPDK with UBSan.
>
> Though the calling code can explicitly request alignment,
> we would prefer to put the alignment constraints as part of the
> structure definition itself.
>
> Such changes are ABI breakages.
>
> Signed-off-by: David Marchand <david.march...@redhat.com>
> ---
> doc/guides/rel_notes/deprecation.rst | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/doc/guides/rel_notes/deprecation.rst
> b/doc/guides/rel_notes/deprecation.rst
> index e2d4125308..4ae561d670 100644
> --- a/doc/guides/rel_notes/deprecation.rst
> +++ b/doc/guides/rel_notes/deprecation.rst
> @@ -57,6 +57,10 @@ Deprecation Notices
> ``__atomic_thread_fence`` must be used for patches that need to be merged
> in
> 20.08 onwards. This change will not introduce any performance degradation.
>
> +* lib: multiple issues relating to unaligned accesses have been detected
> using the UBSan checker.
> + As part of resolving those issues, alignment in some structures will be
> updated in 25.11,
> + namely (but not exhaustively): ``struct rte_stack_lf_head`` and ``struct
> rte_mp_msg``.
> +
> * lib: will fix extending some enum/define breaking the ABI. There are
> multiple
> samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which
> is
> used by iterators, and arrays holding these values are sized with this
> --
> 2.50.0
Acked-by: Konstantin Ananyev <konstantin.anan...@huawei.com>
