Re: [PATCH 2/3] mac80211: create a STA entry for a WDS interface after receiving a beacon

[Felix Fietkau <nbd@openwrt.org>]

On 2011-06-01 6:17 AM, Johannes Berg wrote:
> On Tue, 2011-05-31 at 22:22 +0200, Felix Fietkau wrote:
>>  On 2011-05-31 10:06 PM, Johannes Berg wrote:
>>  >  On Tue, 2011-05-31 at 21:39 +0200, Felix Fietkau wrote:
>>  >>   On 2011-05-31 9:32 PM, Johannes Berg wrote:
>>  >>   >   On Tue, 2011-05-31 at 21:16 +0200, Felix Fietkau wrote:
>>  >>   >>    When a STA entry is created too early, a lot of essential information
>>  >>   >>    required for rate control is missing.
>>  >>   >
>>  >>   >   I don't understand how you can rely on beacons for WDS.
>>  >>   You usually set up WDS links between APs on the same channel, each
>>  >>   running both a normal AP vif and a WDS vif. The remote AP's beacons are
>>  >>   then used to detect the capabilities of the peer.
>>  >
>>  >  I don't think we can rely on "usually" unless we also enforce that
>>  >  somehow. Otherwise this link will basically be dead. There's nothing
>>  >  that requires you to add WDS to an AP interface only after all.
>>  I don't think using WDS without APs makes any sense. Since WDS alone
>>  does not use beacons or probe requests, there's nothing else that would
>>  ensure that rate information, HT capabilities, etc. get exchanged.
>
> I just don't like the fact that you can create a non-functional WDS
> interface by adding it when there's no AP interface.
Actually, I just noticed that ieee80211_assign_perm_addr forces you to 
use the MAC address of an existing AP interface for a WDS interface, 
same as for an AP VLAN interface. So the requirement to also have an AP 
mode interface is not new.

- Felix