Bug also exists in Ubuntu Raring 13.04. ~$ lsb_release -d Description: Ubuntu 13.04 ~$ uname -a Linux BuZZdEE-M2V-Desktop 3.9.0-030900-generic #201304291257 SMP Mon Apr 29 16:58:15 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux ~$ iwconfig wlan0 wlan0 IEEE 802.11bgn ESSID:"ArpaNet" Mode:Managed Frequency:2.412 GHz Access Point: 00:04:0E:D9:C5:4D Bit Rate=11 Mb/s Tx-Power=20 dBm Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off Link Quality=35/70 Signal level=-75 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:5 Invalid misc:32 Missed beacon:0 ~$ dmesg | egrep '\|ath9k' [ 11.344600] ath: EEPROM regdomain: 0x809c [ 11.344604] ath: EEPROM indicates we should expect a country code [ 11.344606] ath: doing EEPROM country->regdmn map search [ 11.344608] ath: country maps to regdmn code: 0x52 [ 11.344610] ath: Country alpha2 being used: CN [ 11.344611] ath: Regpair used: 0x52 [ 11.408407] ieee80211 phy0: Selected rate control algorithm 'ath9k_rate_control' [52600.932743] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00028040 [52600.932989] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [52957.837078] ath: phy0: Failed to stop TX DMA, queues=0x004! [52957.851115] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x000062c0 [52957.851126] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [58627.238520] ath: phy0: Failed to stop TX DMA, queues=0x004! [58629.223346] ath: phy0: Failed to stop TX DMA, queues=0x005! [58629.236328] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [58629.236341] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [58630.141735] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [58630.154668] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [58630.180025] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [58630.267089] ath: phy0: Failed to stop TX DMA, queues=0x005! [58630.279994] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [58630.280027] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [64115.692076] ath: phy0: Failed to stop TX DMA, queues=0x001! [64115.724988] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00028040 [64115.725007] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [64116.717375] ath: phy0: Failed to stop TX DMA, queues=0x001! [64116.730293] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64116.730305] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [64116.795935] ath: phy0: Failed to stop TX DMA, queues=0x001! [64116.808798] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [64116.808808] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [64117.214910] ath: phy0: Failed to stop TX DMA, queues=0x001! [64117.227828] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64117.227840] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [64118.136013] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64118.156036] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64118.168978] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64118.192022] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64118.254549] ath: phy0: Failed to stop TX DMA, queues=0x001! [64118.267492] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [64118.267505] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69038.424110] ath: phy0: Failed to stop TX DMA, queues=0x001! [69038.457088] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00028040 [69038.457108] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69039.436822] ath: phy0: Failed to stop TX DMA, queues=0x005! [69039.449745] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69039.449758] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69039.512088] ath: phy0: Failed to stop TX DMA, queues=0x001! [69039.525003] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69039.525016] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69040.494281] ath: phy0: Failed to stop TX DMA, queues=0x005! [69040.507207] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69040.507219] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69040.572007] ath: phy0: Failed to stop TX DMA, queues=0x001! [69040.584973] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69040.584985] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69041.546161] ath: phy0: Failed to stop TX DMA, queues=0x001! [69041.559072] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69041.559084] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69041.624022] ath: phy0: Failed to stop TX DMA, queues=0x001! [69041.636939] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69041.636952] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69042.614109] ath: phy0: Failed to stop TX DMA, queues=0x005! [69042.627149] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69042.627162] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69042.692075] ath: phy0: Failed to stop TX DMA, queues=0x001! [69042.704981] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69042.704993] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69043.679585] ath: phy0: Failed to stop TX DMA, queues=0x001! [69043.692555] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69043.692568] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69043.756155] ath: phy0: Failed to stop TX DMA, queues=0x001! [69043.769105] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69043.769118] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69044.737131] ath: phy0: Failed to stop TX DMA, queues=0x005! [69044.749816] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69044.749824] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69044.811884] ath: phy0: Failed to stop TX DMA, queues=0x001! [69044.824576] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69044.824584] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69045.792093] ath: phy0: Failed to stop TX DMA, queues=0x001! [69045.805011] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69045.805024] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69045.868558] ath: phy0: Failed to stop TX DMA, queues=0x001! [69045.881487] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00008040 [69045.881500] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69046.275860] ath: phy0: Failed to stop TX DMA, queues=0x001! [69046.288787] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69046.288799] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69048.215551] ath: phy0: Failed to stop TX DMA, queues=0x005! [69048.228542] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69048.228556] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [69049.116014] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69049.136047] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69049.145013] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69049.168047] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69049.232946] ath: phy0: Failed to stop TX DMA, queues=0x001! [69049.245694] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42000020 DMADBG_7=0x00006040 [69049.245702] ath: phy0: Could not stop RX, we could be confusing the DMA engine when we start RX up [71450.029546] ath9k: ath9k: Driver unloaded [71453.701366] ath: EEPROM regdomain: 0x809c [71453.701376] ath: EEPROM indicates we should expect a country code [71453.701381] ath: doing EEPROM country->regdmn map search [71453.701385] ath: country maps to regdmn code: 0x52 [71453.701389] ath: Country alpha2 being used: CN [71453.701393] ath: Regpair used: 0x52 [71453.707665] ieee80211 phy0: Selected rate control algorithm 'ath9k_rate_control'