Linux Ethernet Bridging - Aug 2016 - [Bridge] [PATCH net-next v2 2/2] net: bridge: add per-port multicast flood flag

On Tue, Aug 30, 2016 at 05:23:08PM +0200, Nikolay Aleksandrov via Bridge
wrote:
> diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
> index 1da3221845f1..ed0dd3340084 100644
> --- a/net/bridge/br_if.c
> +++ b/net/bridge/br_if.c
> @@ -362,7 +362,7 @@ static struct net_bridge_port *new_nbp(struct
net_bridge *br,
>  	p->path_cost = port_cost(dev);
>  	p->priority = 0x8000 >> BR_PORT_BITS;
>  	p->port_no = index;
> -	p->flags = BR_LEARNING | BR_FLOOD;
> +	p->flags = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD;
I'm discontent with this new flag becoming the default.

Could you elaborate a little more on your use-case, when/why do
you want/need this flag?

On 31/08/16 03:37, Linus L?ssing wrote:
> On Tue, Aug 30, 2016 at 05:23:08PM +0200, Nikolay Aleksandrov via Bridge
wrote:
>> diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
>> index 1da3221845f1..ed0dd3340084 100644
>> --- a/net/bridge/br_if.c
>> +++ b/net/bridge/br_if.c
>> @@ -362,7 +362,7 @@ static struct net_bridge_port *new_nbp(struct
net_bridge *br,
>>  	p->path_cost = port_cost(dev);
>>  	p->priority = 0x8000 >> BR_PORT_BITS;
>>  	p->port_no = index;
>> -	p->flags = BR_LEARNING | BR_FLOOD;
>> +	p->flags = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD;
> 
> I'm discontent with this new flag becoming the default.
> 
> Could you elaborate a little more on your use-case, when/why do
> you want/need this flag?
> 
The use case is the current default behaviour if we don't make this flag on
by default
then we'll change user-visible default behaviour. Right now we flood
unregistered mcast
traffic by default (if there's no querier and router port, which continues
to function
as before). Also we have the port flags equal to BR_AUTO_MASK by default.

Cheers,
 Nik