Re: [PATCH v3 net-next 2/5] psp: add new netlink cmd for dev-assoc and dev-disassoc

[Bobby Eshleman <bobbyeshleman@gmail.com>]

On Mon, Mar 09, 2026 at 11:34:50AM -0700, Wei Wang wrote:
> From: Wei Wang <weibunny@fb.com>
> 
> The main purpose of this cmd is to be able to associate a
> non-psp-capable device (e.g. veth) with a psp device.
> One use case is if we create a pair of veth/netkit, and assign 1 end
> inside a netns, while leaving the other end within the default netns,
> with a real PSP device, e.g. netdevsim or a physical PSP-capable NIC.
> With this command, we could associate the veth/netkit inside the netns
> with PSP device, so the virtual device could act as PSP-capable device
> to initiate PSP connections, and performs PSP encryption/decryption on
> the real PSP device.
> 
> Signed-off-by: Wei Wang <weibunny@fb.com>

We'll need to follow in your footsteps for TCP devmem + netkit. I wonder
if it is possible to decouple this API from PSP?

I have a hack POC that works similarly to the psp associated dev list
here, but is implicit. It teaches the devmem TX path to allow skbs land
on netkit_xmit() when that nk has been leased a queue from a device that
has the support needed (namely, netmem_tx)... but I expect that if there
is this explicit API, it'll probably be best for devmem to follow suite
instead of the implicit approach.

Best,
Bobby