Re: [PATCH v2 net-next] net/hsr: add protocol version to fill_info output

[Jakub Kicinski <kuba@kernel.org>]

On Wed, 24 Sep 2025 13:21:32 +0200 Ján Václav wrote:
> On Wed, Sep 24, 2025 at 2:06 AM Jakub Kicinski <kuba@kernel.org> wrote:
> > On Mon, 22 Sep 2025 11:37:45 +0200 Jan Vaclav wrote:  
> > >       if (hsr->prot_version == PRP_V1)
> > >               proto = HSR_PROTOCOL_PRP;
> > > +     if (nla_put_u8(skb, IFLA_HSR_VERSION, hsr->prot_version))
> > > +             goto nla_put_failure;  
> >
> > Looks like configuration path does not allow setting version if proto
> > is PRP. Should we add an else before the if? since previous if is
> > checking for PRP already
> >  
> 
> The way HSR configuration is currently handled seems very confusing to
> me, because it allows setting the protocol version, but for PRP_V1
> only as a byproduct of setting the protocol to PRP. If you configure
> an interface with (proto = PRP, version = PRP_V1), it will fail, which
> seems wrong to me, considering this is the end result of configuring
> only with proto = PRP anyways.

I'm not very familiar with HSR or PRP. But The PRP_V1 which has value
of 3 looks like a kernel-internal hack. Or does the protocol actually
specify value 3 to mean PRP?

I don't think there's anything particularly wrong with the code.
The version is for HSR because PRP only has one version, there's no
ambiguity.

But again, I'm just glancing at the code I could be wrong..