Bug 195348

Summary: IP traffic through wifi get stuck on each background scan every five minutes
Product: Base System Reporter: Matthias Apitz <guru>
Component: wirelessAssignee: freebsd-wireless (Nobody) <wireless>
Status: Closed Overcome By Events    
Severity: Affects Some People CC: guru, thj
Priority: ---    
Version: CURRENT   
Hardware: i386   
OS: Any   

Description Matthias Apitz 2014-11-24 20:30:18 UTC
The problem is reproducible fine: I'm running in a loop SCP traffic up
and down to my ISP host; when the background scan every five minutes
takes place the traffic gets STALLED and IP comes not to work again:

Nov 23 17:13:33 unixarea dhclient: New Broadcast Address (wlan0): 192.168.2.255
Nov 23 17:13:33 unixarea dhclient: New Routers (wlan0): 192.168.2.1
Nov 23 17:18:33 unixarea kernel: wlan0: ieee80211_bg_scan: active scan, ticks 36537257 duration 150
Nov 23 17:18:33 unixarea kernel: wlan0: [00:13:f7:0d:08:48] sta power save mode on
Nov 23 17:18:33 unixarea kernel: wlan0: scan_task: chan   7g ->   1g [active, dwell min 20ms max 150ms]
Nov 23 17:18:33 unixarea kernel: wlan0: scan_task: stopped, [ticks 36537415, dwell min 20 scanend 36537408]

from now the interface does not let pass frames anymore

Nov 23 17:18:33 unixarea kernel: wlan0: ieee80211_sta_tim_notify: TIM=1
Nov 23 17:18:34 unixarea last message repeated 3 times
Nov 23 17:18:34 unixarea kernel: wlan0: [00:13:f7:0d:08:48] save frame with age 40, 1 now queued
Nov 23 17:18:34 unixarea kernel: wlan0: [00:13:f7:0d:08:48] save frame with age 0, 2 now queued
Nov 23 17:18:34 unixarea kernel: wlan0: ieee80211_sta_tim_notify: TIM=1
Nov 23 17:18:35 unixarea last message repeated 14 times
Nov 23 17:18:35 unixarea kernel: wlan0: [00:13:f7:0d:08:48] save frame with age 0, 3 now queued
Nov 23 17:18:35 unixarea kernel: wlan0: ieee80211_sta_tim_notify: TIM=1
...

I tested the same in an older 10-ALPHA4 laptop (running r255948 from
October 2013) with the same physical WLAN card; there is no problem with
the bg scans every 5 minutes, it just goes ahead after any scan; this is
an issue in head.