ODroid XU4 $ uname -a Linux computer 4.12.0-rc3-dirty #1 SMP Wed May 31 15:02:05 CDT 2017 armv7l GNU/Linux $ lsusb ... Bus 001 Device 002: ID 2109:2813 VIA Labs, Inc. Bus 001 Device 010: ID 0cf3:7015 Qualcomm Atheros Communications TP-Link TL-WN821N v3 / TL-WN822N v2 802.11n [Atheros AR7010+AR9287] ... ***** Jun 02 16:20:11 computer hostapd[14954]: vwlan0: interface state COUNTRY_UPDATE->HT_SCAN Jun 02 16:20:17 computer hostapd[14954]: 20/40 MHz operation not permitted on channel pri=7 sec=3 based on overlapping BSSes Jun 02 16:20:18 computer kernel: Division by zero in kernel. Jun 02 16:20:18 computer kernel: CPU: 1 PID: 14507 Comm: kworker/u16:2 Tainted: G W 4.12.0-rc3-dirty #1 Jun 02 16:20:18 computer kernel: Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) Jun 02 16:20:18 computer kernel: Workqueue: phy5 ieee80211_scan_work [mac80211] Jun 02 16:20:18 computer kernel: [<c010ee0c>] (unwind_backtrace) from [<c010b61c>] (show_stack+0x10/0x14) Jun 02 16:20:18 computer kernel: [<c010b61c>] (show_stack) from [<c0377708>] (dump_stack+0x88/0x9c) Jun 02 16:20:18 computer kernel: [<c0377708>] (dump_stack) from [<c03755d0>] (Ldiv0_64+0x8/0x18) Jun 02 16:20:18 computer kernel: [<c03755d0>] (Ldiv0_64) from [<bf71c9a4>] (ath9k_get_next_tbtt+0x58/0x5c [ath9k_common]) Jun 02 16:20:18 computer kernel: [<bf71c9a4>] (ath9k_get_next_tbtt [ath9k_common]) from [<bf71cb90>] (ath9k_cmn_beacon_config Jun 02 16:20:18 computer kernel: [<bf71cb90>] (ath9k_cmn_beacon_config_ap [ath9k_common]) from [<bf7898c8>] (ath9k_htc_beacon Jun 02 16:20:18 computer kernel: [<bf7898c8>] (ath9k_htc_beacon_config_ap [ath9k_htc]) from [<bf7885a8>] (ath9k_htc_vif_recon Jun 02 16:20:18 computer kernel: [<bf7885a8>] (ath9k_htc_vif_reconfig [ath9k_htc]) from [<bf78860c>] (ath9k_htc_sw_scan_compl Jun 02 16:20:18 computer kernel: [<bf78860c>] (ath9k_htc_sw_scan_complete [ath9k_htc]) from [<bf506d38>] (__ieee80211_scan_co Jun 02 16:20:18 computer kernel: [<bf506d38>] (__ieee80211_scan_completed [mac80211]) from [<bf507968>] (ieee80211_scan_work+ Jun 02 16:20:18 computer kernel: [<bf507968>] (ieee80211_scan_work [mac80211]) from [<c0133f10>] (process_one_work+0x1d8/0x40 Jun 02 16:20:18 computer kernel: [<c0133f10>] (process_one_work) from [<c0134cb4>] (worker_thread+0x4c/0x564) Jun 02 16:20:18 computer kernel: [<c0134cb4>] (worker_thread) from [<c0139c20>] (kthread+0x14c/0x154) Jun 02 16:20:18 computer kernel: [<c0139c20>] (kthread) from [<c0107c38>] (ret_from_fork+0x14/0x3c) Jun 02 16:20:18 computer hostapd[14954]: Using interface wlan0 with hwaddr <sanitized> and ssid "<sanitized>" Jun 02 16:20:18 computer kernel: IPv6: ADDRCONF(NETDEV_CHANGE): vwlan0: link becomes ready ***** This is a new one on me. The "normal" problem (search shows to be a very old issue) I consistently (daily or multiple times/day) encounter is: ***** Jun 02 14:55:30 computer kernel: usb 1-1.1: ath: firmware panic! exccause: 0x0000000d; pc: 0x0090ae81; badvaddr: 0x10ff4038. Jun 02 14:55:30 computer kernel: usb 1-1.1: USB disconnect, device number 9 Jun 02 14:55:30 computer systemd-networkd[11959]: vwlan0: Lost carrier Jun 02 14:55:30 computer kernel: br0: port 2(vwlan0) entered disabled state Jun 02 14:55:30 computer kernel: wlan0: deauthenticating from <sanitized> by local choice (Reason: 3=DEAUTH_LEAVING) Jun 02 14:55:30 computer kernel: ath: phy4: Failed to wakeup in 500us Jun 02 14:55:30 computer kernel: ath: phy4: Failed to wakeup in 500us Jun 02 14:55:30 computer kernel: ath: phy4: Failed to wakeup in 500us Jun 02 14:55:30 computer kernel: ath: phy4: Failed to wakeup in 500us Jun 02 14:55:30 computer systemd-networkd[11959]: wlan0: Lost carrier Jun 02 14:55:30 computer systemd[1]: Stopping A simple WPA encrypted wireless connection using a static IP... -- Subject: Unit netctl@wlan0.service has begun shutting down -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit netctl@wlan0.service has begun shutting down. Jun 02 14:55:30 computer kernel: device vwlan0 left promiscuous mode Jun 02 14:55:30 computer kernel: br0: port 2(vwlan0) entered disabled state Jun 02 14:55:30 computer audit: ANOM_PROMISCUOUS dev=vwlan0 prom=0 old_prom=256 auid=4294967295 uid=0 gid=0 ses=4294967295 Jun 02 14:55:30 computer hostapd[13218]: vwlan0: AP-STA-DISCONNECTED <sanitized> Jun 02 14:55:30 computer hostapd[13218]: Failed to set beacon parameters Jun 02 14:55:30 computer hostapd[13218]: vwlan0: INTERFACE-DISABLED Jun 02 14:55:30 computer kernel: usb 1-1.1: ath9k_htc: USB layer deinitialized Jun 02 14:55:30 computer systemd[1]: Starting Load/Save RF Kill Switch Status... -- Subject: Unit systemd-rfkill.service has begun start-up -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit systemd-rfkill.service has begun starting up. Jun 02 14:55:30 computer systemd[1]: Started Load/Save RF Kill Switch Status. -- Subject: Unit systemd-rfkill.service has finished start-up -- Defined-By: systemd -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel -- -- Unit systemd-rfkill.service has finished starting up. -- -- The start-up result is done. Jun 02 14:55:30 computer network[13261]: Stopping network profile 'wlan0'... Jun 02 14:55:30 computer kernel: usb 1-1.1: new high-speed USB device number 10 using exynos-ehci Jun 02 14:55:30 computer kernel: usb 1-1.1: New USB device found, idVendor=0cf3, idProduct=7015 Jun 02 14:55:30 computer kernel: usb 1-1.1: New USB device strings: Mfr=16, Product=32, SerialNumber=48 Jun 02 14:55:30 computer kernel: usb 1-1.1: Product: USB WLAN Jun 02 14:55:30 computer kernel: usb 1-1.1: Manufacturer: ATHEROS Jun 02 14:55:30 computer kernel: usb 1-1.1: SerialNumber: 12345 Jun 02 14:55:30 computer kernel: usb 1-1.1: ath9k_htc: Firmware ath9k_htc/htc_7010-1.4.0.fw requested Jun 02 14:55:30 computer kernel: usb 1-1.1: ath9k_htc: Transferred FW: ath9k_htc/htc_7010-1.4.0.fw, size: 72812 Jun 02 14:55:30 computer kernel: ath9k_htc 1-1.1:1.0: ath9k_htc: HTC initialized with 45 credits Jun 02 14:55:31 computer kernel: ath9k_htc 1-1.1:1.0: ath9k_htc: FW Version: 1.4 Jun 02 14:55:31 computer kernel: ath9k_htc 1-1.1:1.0: FW RMW support: On Jun 02 14:55:31 computer kernel: ath: EEPROM regdomain: 0x809c Jun 02 14:55:31 computer kernel: ath: EEPROM indicates we should expect a country code Jun 02 14:55:31 computer kernel: ath: doing EEPROM country->regdmn map search Jun 02 14:55:31 computer kernel: ath: country maps to regdmn code: 0x52 Jun 02 14:55:31 computer kernel: ath: Country alpha2 being used: CN Jun 02 14:55:31 computer kernel: ath: Regpair used: 0x52 Jun 02 14:55:31 computer kernel: ieee80211 phy5: Atheros AR9287 Rev:2 Jun 02 14:55:31 computer kernel: IPv6: ADDRCONF(NETDEV_UP): vwlan0: link is not ready Jun 02 14:55:31 computer hostapd[13218]: vwlan0: INTERFACE-ENABLED Jun 02 14:55:31 computer network[13261]: Stopped network profile 'wlan0' ***** I don't know the particular reason for this one. At first it would happen every time I compiled anything (all cpu used). Then I added the ZTE Mobley to the USB hub. Even after removing the Mobley, the panic would still happen often. I then recompiled the kernel so only the 4 LITTLE cpus were used (big.LITTLE support+switcher), but the panic still happens sometimes. Now the consistency seems to come from the wireless adapter used as both AP and managed client.
