Re: [PATCH net-next v3 3/3] nfp: implement xfrm callbacks and expose ipsec offload feature to upper layer

[Leon Romanovsky <leon@kernel.org>]

On Wed, Nov 09, 2022 at 06:58:44AM +0000, Yinjun Zhang wrote:
> On Mon, 7 Nov 2022 08:14:12 +0200, Leon Romanovsky wrote:
> > On Tue, Nov 01, 2022 at 12:02:48PM +0100, Simon Horman wrote:
> <...>
> > > +
> > > +	/* General */
> > > +	switch (x->props.mode) {
> > > +	case XFRM_MODE_TUNNEL:
> > > +		cfg->ctrl_word.mode = NFP_IPSEC_PROTMODE_TUNNEL;
> > > +		break;
> > > +	case XFRM_MODE_TRANSPORT:
> > > +		cfg->ctrl_word.mode = NFP_IPSEC_PROTMODE_TRANSPORT;
> > > +		break;
> > > +	default:
> > > +		nn_err(nn, "Unsupported mode for xfrm offload\n");
> > 
> > There are no other modes.
> 
> Sorry this comment was neglected, but I have to say this is a good practice to avoid
> newly introduced mode in future sneaking into HW while it's not supported.

There is a subtitle difference between not-existent flows and
not-supported ones. Good practice is to rely on upper level API to do
the right thing from the beginning.

Thanks