Firmware panic, 'Unable to remove station entry...'

[Jason Conti]

Hello,

With my TP-Link TL-WN821N wireless adapter using the ath9k_htc module
I am occasionally
running into the following error, which results in hanging many
processes on the system:

[ 3501.052975] usb 1-2: ath: firmware panic! exccause: 0x0000000d; pc:
0x0090a641; badvaddr: 0x12345678.
[ 3517.088168] wlan0: moving STA f4:ec:38:ec:42:02 to state 3
[ 3517.088180] wlan0: moving STA f4:ec:38:ec:42:02 to state 2
[ 3519.088060] ath: phy0: Unable to remove station entry for: f4:ec:38:ec:42:02
[ 3519.088078] wlan0: moving STA f4:ec:38:ec:42:02 to state 1
[ 3519.088084] wlan0: Removed STA f4:ec:38:ec:42:02
[ 3519.088240] wlan0: Destroyed STA f4:ec:38:ec:42:02

I filed a bug with more information on launchpad:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1301558

I'm working on debugging the issue but I thought I would ask here in
case anyone had any idea
about the values in the firmware panic string.

Thanks,
Jason Conti