Bug 165306

Summary:	[ath] race conditions between scanning and beacon timeout programming
Product:	Base System	Reporter:	Adrian Chadd <adrian>
Component:	wireless	Assignee:	freebsd-wireless (Nobody) <wireless>
Status:	Open ---
Severity:	Affects Only Me
Priority:	Normal
Version:	9.0-RELEASE
Hardware:	Any
OS:	Any

Description Adrian Chadd freebsd_committer

2012-02-20 02:40:09 UTC

There seem to be issues where net80211 doesn't quite get the "beacon miss" notification. It stays associated, the beacon interrupt/notification isn't occuring.

Adding on reset/beacon debugging (0x20 + 0x80) on ath0 (sysctl dev.ath.0.debug=0xa0) didn't show any beacon miss interrupts, software or hardware.

This is with one VAP STA on an AR9280.

What I think is happening is:

* the transition to -> RUN doesn't program in any beacon timers by default - it waits for the first beacon to be RX'ed before it programs in timers;
* but if it loses connectivity during a scan, the beacon timers won't ever be reprogrammed, as no beacons will occur.

So it stays associated.

Fix: 

It may be that we need to:

* program in some beacon TSF value for the initial state transition to RUN, and hope that a new beacon will come in and reprogram the timers.
* .. or also enable swbeacon support too for single-VAP STA mode?
How-To-Repeat: The above should be doable to reproduce - just enable beacon debugging, then do a scan and kill the AP whilst the station is scanning.

Comment 1 Adrian Chadd freebsd_committer

2012-02-20 02:42:58 UTC

Responsible Changed
From-To: freebsd-bugs->freebsd-wireless

Reassign

Comment 2 Eitan Adler freebsd_committer

2018-05-28 19:47:01 UTC

batch change:

For bugs that match the following
-  Status Is In progress 
AND
- Untouched since 2018-01-01.
AND
- Affects Base System OR Documentation

DO:

Reset to open status.


Note:
I did a quick pass but if you are getting this email it might be worthwhile to double check to see if this bug ought to be closed.