Comment 43 for bug 64173

Hi,

Dan Williams, NM developer, wrote this on this topic on the mailing list:

The core of the problem is that this is may be a driver issue. There's
no reason why re-association should take more than a 5 - 10 seconds at
most. Papering over the issue in NetworkManager without investigating
why the driver is dropping association for more than 8 seconds is just
the wrong answer.

Without a lot more investigation into why the drivers are having
problems, and why only _certain_ drivers are having problems, the patch
is incorrect. Patches that are not investigated are not going to get
applied just like that.

I'd like to see driver traces from madwifi and ipw2200 that indicate why
the association was dropped, and what the card is doing to achieve
re-association during those 10 - 20 seconds. Remember, during the 10 -
20 seconds, the driver should _not_ be able to pass traffic if it's
really disassociated from the AP.

If the driver is actually associated to the AP, then it needs to report
that correctly via WEXT, which is the noticed by wpa_supplicant, which
is then noticed by NetworkManager. So we need to verify that the driver
is doing the right thing first, before crying wolf and patching
NetworkManager for something that in reality may not actually be
required. A clear picture of the issue is required.

Remember, when you encounter errant behavior, there's a lot more in the
stack than just NetworkManager, and that includes both wpa_supplicant
and the drivers. Historically, drivers have been quite inconsistent and
buggy. That's not to say that NM is bug-free at all, just that many
behavioral problems like this can be traced back to drivers behaving
badly.
---- end here ----

So it's not NM's fault to use all features of the wireless stack (software + hardware) and relying on correct behaviour.
Manual configurations and wpa_supplicant don't show some of the encountered problems, as they make different assumptions and use different functions.
Please bug:
a) hardware vendors for broken hardware
b) driver developers for each "cooking their own soup" and not using common standards

As for the wireless driver developers, I hope the new 80211 stack will be the last (and best) change in infrastructure and they migrate ASAP.

Nikolaus