Re: [RFC PATCH net-next 2/5] net: 8021q: vlan_dev: add vid tag for uc and mc address lists

From: Florian Fainelli
Date: Tue Jan 08 2019 - 13:21:40 EST


On 1/7/19 9:01 PM, Florian Fainelli wrote:
> Le 12/4/18 Ã 4:04 PM, Ivan Khoronzhuk a ÃcritÂ:
>> On Tue, Dec 04, 2018 at 11:49:27AM -0800, Florian Fainelli wrote:
>>
>> ...
>>
>>>>
>>>> I was thinking also about pinned list of vlans to the address, but in
>>>> this case this information also has to be synced by members of device
>>>> chain,
>>>> because it can be modified on any device level and it looks not very
>>>> friendly,
>>>> and at the end address space has addresses with pinned lists of vlans
>>>> with
>>>> their pointers. But keeping this stuff in sync is not simplest decision.
>>>>
>>>>
>>>
>>> I really think we are not communicating properly, it really seems to me
>>> that if you had the information about the upper device trying to add an
>>> address to the lower device filter's either through notification or call
>>> to ndo_set_rxmode, you could be solving your problems. What are we
>>> missing here?
>>
>> Sry, missed this one. The problem in getting the owner of address.
>> Just simple case: vlan/macvlan/real_dev or vlan/.../.../real_dev
>>
>> The real dev hasn't simple way to get vid the address belong to, or it has?
>
> Humm looks like your right, by the time the address lists are
> synchronized (e.g: from = vlan_dev, to = real_dev), we lost that
> information. It looks like I just managed to find such an use case
> myself with VLAN filtering enabled on a bridge (so switch is VLAN aware)
> and a VLAN device created on the bridge (br0.42) but with IGMP snooping
> turned off (so we don't get HOST_MDB notifications with correct VLAN ID).
>
> Maybe keeping the "from" net_device within the address list that is
> processed by ndo_set_rx_mode() will do the job though?
>
> Then you can do things like:
>
> if (is_vlan_dev(ha->dev) && ha->dev != dev)
> vid = vlan_dev_vlan_id(ha->dev);
>
> and it should scale to any type of stacked device, regardless of VID or
> something else that we need?
>
> Can you remind me of your use case again? Is it because your switch has
> VLAN filtering enabled and you need to make sure that MC addresses on
> VLAN device get programmed into the switch's multicast database with
> correct VID?

Ivan, can you see if the following would work for you:

https://github.com/ffainelli/linux/commit/19e173ebdcdd32f5f5b5ef29049e35d33ad058f2

this should be more scalable approach in that we can support HOST_MDB
notifications from the bridge, the same way we would get notified about
IGMP snooping from the bridge and this does not impact any other driver
than those that elect to receive switchdev object notifications, which
cpsw should really implement by now...
--
Florian