[PATCH v4 0/1] mbuf: add runtime metadata dynamic-field storage

[Stephen Hemminger]

On Fri, 9 Oct 2026 18:12:20 +0000
"Randy Tice (rtice)" <rtice at cisco.com> wrote:

> Stephen,
> I’m thinking, perhaps the best path forward for now, is to continue using a private mbuf layout and carry the collateral internally — at least for now. The changes are getting well beyond the initial desired impacts and has potential make things become unstable.
> 
> I would love to see some sort of solution along these lines in the future so we can discontinue the use of a private patch. To be clear, the solution is not built around cnxk, cnxk is just impacted — we have several other platform builds that do not use cnxk but we still carry the metadata in the mbuf itself for performance reasons.
> 
> WRT the skip functions, we fit under the 384 max for wqe but there’s no room for additional growth beyond that with how it’s laid out. The other 2 are not as sensitive to the size but still have valid limits which are well beyond our use case. Today we carry 256 bytes which caps us on wqe.
> 
> That said, we plan to discuss internally next week on how to move forward as we prep for our v25.11 upgrade work. I want to thank you and Morten, however, for your time and support on this work.
> Regards,
> -rt

I do think CNXK needs fixing.