Re: [PATCH net-next 0/4] psp: make tx key ops optional for drivers

[Daniel Zahka]

On Mon Sep 7, 2026 at 8:00 PM EDT, patchwork-bot+netdevbpf wrote:
> Hello:
>
> This series was applied to netdev/net-next.git (main)
> by Jakub Kicinski <kuba@xxxxxxxxxx>:
>
> On Thu, 03 Sep 2026 18:33:58 -0700 you wrote:
>> This is the first of two series which together implement rekeying PSP
>> protected tcp connections. Here are both series together on github:
>> https://github.com/danieldzahka/linux/commits/psp-rekey-split/
>> 
>> This first series is mostly non-functional changes, except for the minor
>> difference that netdevsim driver implements tx key ops. Its tx key ops
>> were basically NOPs, and in the future PSP core can subsume the assoc
>> counting that it was doing.
>> 
>> [...]
>
> Here is the summary with links:
>   - [net-next,1/4] psp: refactor psp_dev_tx_key_del()
>     https://git.kernel.org/netdev/net-next/c/7b26ff200739
>   - [net-next,2/4] psp: move code from psp_sock_assoc_set_tx() into helper functions
>     https://git.kernel.org/netdev/net-next/c/4d3a7d1104eb
>   - [net-next,3/4] psp: allow drivers to omit tx key add/del ops
>     https://git.kernel.org/netdev/net-next/c/1e16b303109f
>   - [net-next,4/4] netdevsim: psp: drop tx key ops
>     https://git.kernel.org/netdev/net-next/c/da630d1da2b1
>
> You are awesome, thank you!

Thanks. I think applying was the right move, but I would like to
highlight something that sashiko flagged on patch 4, as I think it will
need to be addressed with its own series. The hazard is preexisting and
much broader than the way sashiko talks about it. 

The high level idea is that netdev core should probably take extra care
to make sure users of sk_validate_xmit_skb (psp and ktls) cannot clobber
what each other has set for that callback. In the case of psp vs. ktls,
there are probably fundamental reasons why these should be kept mutually
exclusive and their uapis should reject attempts to transition between
them.

More generally however, any offloads wishing to claim
sk_validate_xmit_skb should be considered mutually exclusive, and netdev
core may benefit from a generic system to enforce ownership. That would
help in case another user of sk_validate_xmit_skb comes along later.