Re: [PATCH net-next 01/10] net: bridge: add document for IFLA_BR enum

[Hangbin Liu <liuhangbin@gmail.com>]

On Sun, Nov 19, 2023 at 07:21:25PM +0100, Andrew Lunn wrote:
> > > + * @IFLA_BR_GROUP_FWD_MASK
> > > + *   The group forward mask. This is the bitmask that is applied to
> > > + *   decide whether to forward incoming frames destined to link-local
> > > + *   addresses. The addresses of the form is 01:80:C2:00:00:0X, which
> > > + *   means the bridge does not forward any link-local frames coming on
> > > + *   this port).
> > > + *
> > > + *   The default value is 0.
> 
> Where was the default value of 0 derived from?

I doc it as 0 because I saw in br_dev_setup()

        br->stp_enabled = BR_NO_STP;
        br->group_fwd_mask = BR_GROUPFWD_DEFAULT;
        br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT;

and #define BR_GROUPFWD_DEFAULT     0

Thanks
Hangbin
> 
> br_handle_frame() seems to handle 01-80-C2-00-00-00 using is used for
> BPDUs. 01-80-C2-00-00-01 is explicitly dropped, since its Pause, which
> i doubt you want to forward. LLDP has some level of processing.
> 
> Should the default value reflect this?
> 
>        Andrew