[FS#176] Disapearing radios for ath9k introduced between August 31 and September 4th

[LEDE Bugs]

The following task has a new comment added:

FS#176 - Disapearing radios for ath9k introduced between August 31 and September 4th
User who did this - Franz Bettag (fbettag)

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Hey guys,

i've been running r1712 from nbd's staging tree and everything was fine until like 10 minutes ago:

root at wifi-food:~# uptime
 18:26:06 up 2 days,  5:02,  load average: 0.00, 0.00, 0.00

root at wifi-food:~# dmesg
...
[159489.201588] br-lan: port 3(wlan1) neighbor 7fff.00:0d:b9:1f:87:cc lost
[159489.208291] br-lan: topology change detected, propagating
[185348.587359] ath: phy1: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000062c0
[185365.647171] br-lan: port 3(wlan1) neighbor 7fff.00:0d:b9:1f:87:cc lost
...

root at wifi-food:~# cat /sys/kernel/debug/ieee80211/phy0/ath9k/reset
    Baseband Hang:  0
Baseband Watchdog:  0
   Fatal HW Error:  0
      TX HW error:  0
 Transmit timeout:  0
     TX Path Hang:  0
      PLL RX Hang:  0
         MAC Hang: 91
     Stuck Beacon:  1
        MCI Reset:  0
Calibration error:  0
Tx DMA stop error:  0
Rx DMA stop error:  0

root at wifi-food:~# cat /sys/kernel/debug/ieee80211/phy1/ath9k/reset
    Baseband Hang:  0
Baseband Watchdog:  0
   Fatal HW Error:  1
      TX HW error:  0
 Transmit timeout:  0
     TX Path Hang: 2037
      PLL RX Hang:  0
         MAC Hang:  3
     Stuck Beacon: 983
        MCI Reset:  0
Calibration error:  0
Tx DMA stop error: 3023
Rx DMA stop error:  1

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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=176#comment531