Re: [EXT] Re: [PATCH net-next v5 3/7] net: macsec: indicate next pn update when offloading

[Radu Pirea (OSS)]

On 26.09.2023 15:16, Igor Russkikh wrote:
> Hi guys,
>
> > On 21.09.2023 18:11, Sabrina Dubroca wrote:
> > > 2023-09-20, 12:22:33 +0300, Radu Pirea (NXP OSS) wrote:
> > > > Indicate next PN update using update_pn flag in macsec_context.
> > > > Offloaded MACsec implementations does not know whether or not the
> > > > MACSEC_SA_ATTR_PN attribute was passed for an SA update and assume
> > > > that next PN should always updated, but this is not always true.
> > >
> > > This should probably go through net so that we can fix some drivers
> > > that are currently doing the wrong thing. octeontx2 should be
> > > fixable. atlantic looks like it would reset the PN to whatever was
> > > read during the last dump, and it's unclear if that can be fixed
> > > (AFAIU set_egress_sa_record writes the whole config at once).  mscc
>
> Thats correct, atlantic hardware requires full table to be in data buffer registers.
> I really doubt its possible to skip PN writing.
>
> > > doesn't seem to modify the PN (even if requested -- should it should
> > > reject the update), and mlx5 doesn't allow PN update (by storing the
> > > initial value of next_pn on SA creation).
> >
> > I updated octeontx2, mssc and mlx5. Atlantic is unclear.
> >
> > Mark, Igor, in the atlantic MACsec driver, can the SAs be updated
> > without a PN update?
>
> Reviewed the code and the docs I have - my view is it can not.
> All the packed record in macsec_api.c:set_egress_sa_record is expected by hardware in full.

Ok. I will not touch atlantic.

--
Radu P.