On 1/29/19 11:36 PM, Ido Schimmel wrote:
> On Tue, Jan 29, 2019 at 04:55:37PM -0800, Florian Fainelli wrote:
>> Some Ethernet switches might not be able to support disabling multicast
>> flooding globally when e.g: several bridges span the same physical
>> device, propagate the return value of br_mc_disabled_update() such that
>> this propagates correctly to user-space.
>>
>> Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
>> ---
>> net/bridge/br_multicast.c | 23 ++++++++++++++++-------
>> 1 file changed, 16 insertions(+), 7 deletions(-)
>>
>> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
>> index 3aeff0895669..aff5e003d34f 100644
>> --- a/net/bridge/br_multicast.c
>> +++ b/net/bridge/br_multicast.c
>> @@ -813,20 +813,22 @@ static void br_ip6_multicast_port_query_expired(struct
>> timer_list *t)
>> }
>> #endif
>>
>> -static void br_mc_disabled_update(struct net_device *dev, bool value)
>> +static int br_mc_disabled_update(struct net_device *dev, bool value)
>> {
>> struct switchdev_attr attr = {
>> .orig_dev = dev,
>> .id = SWITCHDEV_ATTR_ID_BRIDGE_MC_DISABLED,
>> - .flags = SWITCHDEV_F_DEFER,
>> + .flags = SWITCHDEV_F_DEFER | SWITCHDEV_F_SKIP_EOPNOTSUPP,
>
> Actually, since the operation is deferred I don't think the return value
> from the driver is ever checked. Can you test it?
You are right, you get a WARN() from switchdev_attr_port_set_now(), but
this does not propagate back to the caller, so you can still create a
bridge device and enslave a device successfully despite getting warnings
on the console.
>
> I think it would be good to convert the attributes to use the switchdev
> notifier like commit d17d9f5e5143 ("switchdev: Replace port obj add/del
> SDO with a notification") did for objects. Then you can have your
> listener veto the operation in the same context it is happening.
Alright, working on it. Would you do that just for the attr_set, or for
attr_get as well (to be symmetrical)?
--
Florian
