[FS#13] Ath9k AP stays up for connected clients but doesn't show in scan on new ones

[LEDE Bugs]

The following task has a new comment added:

FS#13 - Ath9k AP stays up for connected clients but doesn't show in scan on new ones
User who did this - pmgp (mgondium)

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LEDE Reboot SNAPSHOT r2726-0e947112bf from nbd's staging, TPLINK 1043ND v1

radio no longer "disappears" but clients drop constantly.

echo 0xffffffff >/sys/kernel/debug/ieee80211/phy0/ath9k/debug
logs *non-stop* for slots 0-7:
(...)
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.158229] ath: phy0: slot: 0 tsf: 117760017 tsftu: 115000
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.163860] ath: phy0: disable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.167330] ath: phy0: resume beacon xmit after 1 misses
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.172670] ath: phy0: Transmitting beacon for slot: 0
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.177867] ath: phy0: Enable TXE on queue: 9
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.182900] ath: phy0: enable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.186302] ath: phy0: AR_IMR 0x918104b0 IER 0x1
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.190955] ath: phy0: disable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.195022] ath: phy0: enable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.198374] ath: phy0: AR_IMR 0x918104b0 IER 0x1
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.217797] ath: phy0: disable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.221343] ath: phy0: enable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.224725] ath: phy0: disable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.228152] ath: phy0: AR_IMR 0x918104b0 IER 0x0
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.233299] ath: phy0: enable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.236658] ath: phy0: disable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.240090] ath: phy0: AR_IMR 0x918104b0 IER 0x0
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.245519] ath: phy0: enable IER
Sun Jan  1 22:10:15 2017 kern.debug kernel: [  191.248871] ath: phy0: AR_IMR 0x918104b0 IER 0x1
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.265562] ath: phy0: disable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.269079] ath: phy0: enable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.272422] ath: phy0: AR_IMR 0x918104b0 IER 0x1
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.286231] ath: phy0: missed 1 consecutive beacons
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.320187] ath: phy0: disable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.323758] ath: phy0: enable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.327109] ath: phy0: disable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.330543] ath: phy0: AR_IMR 0x918104b0 IER 0x0
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.335976] ath: phy0: enable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.339342] ath: phy0: disable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.342780] ath: phy0: AR_IMR 0x918104b0 IER 0x0
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.348027] ath: phy0: enable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.351374] ath: phy0: AR_IMR 0x918104b0 IER 0x1
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.367895] ath: phy0: disable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.371417] ath: phy0: enable IER
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.374792] ath: phy0: AR_IMR 0x918104b0 IER 0x1
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.393232] ath: phy0: listenTime=1222 OFDM:3 errs=96/s CCK:2 errs=120/s ofdm_turn=1
Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.401046] ath: phy0: Calibration @4294956434 finished:   ani, caldone: true
(...)


other messages include:

Sun Jan  1 22:10:16 2017 kern.debug kernel: [  191.528526] ath: phy0: Error: rs_phyer=0x1f not a radar error
Sun Jan  1 22:10:18 2017 kern.debug kernel: [  193.334231] ath: phy0: missed 1 consecutive beacons
Sun Jan  1 22:10:18 2017 kern.debug kernel: [  193.626947] ath: phy0: **** ccklevel 2=>1, rssi=0[lo=7 hi=40]
Sun Jan  1 22:10:19 2017 kern.debug kernel: [  194.244704] ath: phy0: Transmitting beacon for slot: 0
Sun Jan  1 22:10:19 2017 kern.debug kernel: [  194.249871] ath: phy0: Enable TXE on queue: 9
Sun Jan  1 22:10:19 2017 kern.debug kernel: [  194.358231] ath: phy0: missed 1 consecutive beacons
Sun Jan  1 22:10:19 2017 kern.debug kernel: [  194.500038] ath: phy0: Error: rs_phyer=0x1f not a radar error
Sun Jan  1 22:10:22 2017 kern.debug kernel: [  197.587975] ath: phy0: listenTime=452 OFDM:3 errs=70/s CCK:3 errs=285/s ofdm_turn=1
Sun Jan  1 22:10:22 2017 kern.debug kernel: [  197.595745] ath: phy0: **** ccklevel 3=>4, rssi=0[lo=7 hi=40]
Sun Jan  1 22:10:22 2017 kern.debug kernel: [  197.601537] ath: phy0: ** ch 2442: level 3=>4[def:2] firstep[level]=8 ini=2
Sun Jan  1 22:10:22 2017 kern.debug kernel: [  197.608566] ath: phy0: ** ch 2442: level 3=>4[def:2] firstep_low[level]=8 ini=6
Sun Jan  1 22:10:22 2017 kern.debug kernel: [  197.615936] ath: phy0: ANI parameters: SI=3, ofdmWS=on FS=4 MRCcck=off listenTime=452 ofdmErrs=32 cckErrs=129

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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=13#comment1137