misc/163574: [net80211] overly-frequent HT occupancy changes

[Adrian Chadd]

>Number:         163574
>Category:       misc
>Synopsis:       [net80211] overly-frequent HT occupancy changes
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Dec 23 19:40:11 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Adrian Chadd
>Release:        FreeBSD-10.0, on a TP-WR1043ND router.
>Organization:
FreeBSD
>Environment:
FreeBSD home-11bg-ap 10.0-CURRENT FreeBSD 10.0-CURRENT #39: Thu Jan  1 08:00:00 WST 1970     adrian at dummy:/home/adrian/work/freebsd/git/adrianchadd-freebsd-work/obj/mipseb/mips.mipseb/home/adrian/work/freebsd/git/adrianchadd-freebsd-work/adrianchadd-freebsd-work/sys/TP-WN1043ND  mips

>Description:
When running this tplink in occupied 2.4GHz space, the AP instance frequently bounces between these states:

wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x13
wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x11
wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x13
wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x11
wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x13
wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x11
wlan0: [00:19:e0:66:66:68] HT bss occupancy change: 2 sta, 2 ht, 1 ht40, non-HT sta present, HT protmode now 0x13

. I'm not sure whether it's a problem but it is occuring very very frequently and this may be interfering with station operation.
>How-To-Repeat:
* enable 11n
* throw the AP into a busy 2.4ghz environment with non-11n stuff around you
* wlandebug +11n
>Fix:
Not known.

>Release-Note:
>Audit-Trail:
>Unformatted: