Kernel bug/crash when trying to connect Tinker Board S as WiFi AP

prcarp · March 28, 2021

Armbianmonitor:

I have a brand new Tinker Board S with the latest Armbian buster installed. I have hostapd set up for the board to be a WiFi access point. I can see the SSID on my Windows and mobile devices but when I connect, hostapd tells me an error code 8 and that the device is disassociated. I don't think this is the issue as the kernel panics at exactly the same time. Here is the output from dmesg:

[  101.279674] ------------[ cut here ]------------
[  101.284852] kernel BUG at mm/slub.c:4117!
[  101.289337] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
[  101.295860] Modules linked in: fuse rtc_ds1307 xt_state xt_conntrack nft_counter nft_chain_nat xt_MASQUERADE nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_compat nf_tables nfnetlink snd_soc_simple_card snd_soc_simple_card_utils snd_usb_audio snd_hwdep snd_usbmidi_lib snd_rawmidi snd_seq_device hantro_vpu(C) snd_soc_rockchip_i2s snd_soc_hdmi_codec snd_soc_rockchip_pcm rockchip_rga snd_soc_core v4l2_h264 snd_pcm_dmaengine videobuf2_dma_contig videobuf2_dma_sg snd_pcm videobuf2_vmalloc v4l2_mem2mem videobuf2_memops videobuf2_v4l2 snd_timer videobuf2_common snd soundcore dw_wdt rk_crypto syscon_reboot_mode reboot_mode rk3288_gpiomem r8723bs(C) rockchip_thermal cpufreq_dt zram ip_tables gpio_keys panfrost gpu_sched dw_hdmi_i2s_audio dw_hdmi_cec realtek
[  101.371009] CPU: 0 PID: 2294 Comm: RTW_CMD_THREAD Tainted: G         C        5.10.21-rockchip #21.02.3
[  101.381513] Hardware name: Rockchip (Device Tree)
[  101.386781] PC is at kfree+0x49c/0x524
[  101.390971] LR is at nl80211_send_station+0x964/0x100c
[  101.396717] pc : [<c02c9ebc>]    lr : [<c0ec8430>]    psr: 40070013
[  101.403723] sp : c404fd10  ip : c404fd50  fp : c404fd4c
[  101.409565] r10: c1506808  r9 : 00023454  r8 : c1772340
[  101.415406] r7 : eee1d454  r6 : c0ec8430  r5 : c0fad7a8  r4 : 00000000
[  101.422705] r3 : eee1d458  r2 : 00000000  r1 : c793df78  r0 : c0fad7a8
[  101.430006] Flags: nZcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[  101.437985] Control: 10c5387d  Table: 07ca406a  DAC: 00000051
[  101.444411] Process RTW_CMD_THREAD (pid: 2294, stack limit = 0xabe5bfbc)
[  101.451905] Stack: (0xc404fd10 to 0xc4050000)
[  101.456770] fd00:                                     00000011 00000000 c0fad7a8 c6124190
[  101.465921] fd20: c793df1c c404fdf8 c4cc4780 00000011 00000000 c0fad7a8 c612418c c1506808
[  101.475071] fd40: c404fdac c404fd50 c0ec8430 c02c9a2c 00000005 00000013 c404fd74 00000000
[  101.484221] fd60: c1506808 c6124030 c612418c c6124014 e3500000 ba00005c 0008d8ec d3fcf9d2
[  101.493371] fd80: f08db550 c342c9e0 00000000 c342c000 00000a20 c793df0a c404fdf8 c4cc4780
[  101.502521] fda0: c404fdf4 c404fdb0 c0ec910c c0ec7ad8 00000000 c342c800 c342c000 c793df0a
[  101.511671] fdc0: c404fdf8 c1506808 00000008 c1506808 0000001c 00000000 00000000 bf0ac050
[  101.520821] fde0: c793e980 ffff3def c404feec c404fdf8 bf0a1ffc c0ec9088 00000000 00000000
[  101.529971] fe00: c010d19c 00060040 00000fff d3fcf9d2 c010c214 c1506808 d3fcf9d2 00000006
[  101.539120] fe20: 00000000 00000000 00000000 ffff3def c404fe64 c404fe40 bf084e68 bf084b5c
[  101.548270] fe40: c404fe74 c404fe50 c010c214 c010d11c c1506808 00000000 c0fb4d9c c1504900
[  101.557420] fe60: bf0ac050 c793e980 c793df1c 0000005c c404fec4 c404fe80 c02cba38 c028872c
[  101.566570] fe80: bf05ceb4 c02c9b18 c2001d80 c793df80 00ffff00 ffffe000 00000078 c793df00
[  101.575720] fea0: c404febc c012af1c c0fad8e8 c0fad7a8 c404fed4 c404fec0 c012af1c c01526f4
[  101.584870] fec0: bf05cf10 f11dff84 c404feec d3fcf9d2 f08da000 f11dff84 00000078 c793df00
[  101.594020] fee0: c404ff0c c404fef0 bf05cf28 bf0a1f88 f08db000 00000000 f08db4b8 c1504900
[  101.603170] ff00: c404ff24 c404ff10 bf067dd8 bf05cd6c f08db000 f08dd000 c404ff74 c404ff28
[  101.612320] ff20: bf055930 bf067d58 60000013 c60ad600 f08db49c f08da000 bf0b4000 c342da00
[  101.621470] ff40: c404e000 f08db480 c404ff74 c60ad600 c543f640 c404e000 bf05579c f08da000
[  101.630620] ff60: 00000000 c61037c8 c404ffac c404ff78 c0149700 bf0557a8 c60ad630 c60ad630
[  101.639769] ff80: 00000000 c543f640 c0149564 00000000 00000000 00000000 00000000 00000000
[  101.648919] ffa0: 00000000 c404ffb0 c0100148 c0149570 00000000 00000000 00000000 00000000
[  101.658068] ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[  101.667217] ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
[  101.676360] Backtrace:
[  101.679110] [<c02c9a20>] (kfree) from [<c0ec8430>] (nl80211_send_station+0x964/0x100c)
[  101.687970]  r10:c1506808 r9:c612418c r8:c0fad7a8 r7:00000000 r6:00000011 r5:c4cc4780
[  101.696726]  r4:c404fdf8
[  101.699566] [<c0ec7acc>] (nl80211_send_station) from [<c0ec910c>] (cfg80211_new_sta+0x90/0x1bc)
[  101.709290]  r10:c4cc4780 r9:c404fdf8 r8:c793df0a r7:00000a20 r6:c342c000 r5:00000000
[  101.718045]  r4:c342c9e0
[  101.720945] [<c0ec907c>] (cfg80211_new_sta) from [<bf0a1ffc>] (rtw_cfg80211_indicate_sta_assoc+0x80/0x9c [r8723bs])
[  101.732614]  r10:ffff3def r9:c793e980 r8:bf0ac050 r7:00000000 r6:00000000 r5:0000001c
[  101.741369]  r4:c1506808
[  101.744319] [<bf0a1f7c>] (rtw_cfg80211_indicate_sta_assoc [r8723bs]) from [<bf05cf28>] (rtw_stassoc_event_callback+0x1c8/0x1d4 [r8723bs])
[  101.758130]  r7:c793df00 r6:00000078 r5:f11dff84 r4:f08da000
[  101.764572] [<bf05cd60>] (rtw_stassoc_event_callback [r8723bs]) from [<bf067dd8>] (mlme_evt_hdl+0x8c/0xb4 [r8723bs])
[  101.776345]  r7:c1504900 r6:f08db4b8 r5:00000000 r4:f08db000
[  101.782788] [<bf067d4c>] (mlme_evt_hdl [r8723bs]) from [<bf055930>] (rtw_cmd_thread+0x194/0x3d4 [r8723bs])
[  101.793585]  r5:f08dd000 r4:f08db000
[  101.797647] [<bf05579c>] (rtw_cmd_thread [r8723bs]) from [<c0149700>] (kthread+0x19c/0x1b4)
[  101.806992]  r10:c61037c8 r9:00000000 r8:f08da000 r7:bf05579c r6:c404e000 r5:c543f640
[  101.815747]  r4:c60ad600
[  101.818586] [<c0149564>] (kthread) from [<c0100148>] (ret_from_fork+0x14/0x2c)
[  101.826662] Exception stack(0xc404ffb0 to 0xc404fff8)
[  101.832305] ffa0:                                     00000000 00000000 00000000 00000000
[  101.841455] ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[  101.850603] ffe0: 00000000 00000000 00000000 00000000 00000013 00000000
[  101.858003]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0149564
[  101.866758]  r4:c543f640
[  101.869594] Code: eaffff17 e5973004 e3130001 1affff83 (e7f001f2)
[  101.876416] ---[ end trace 8e72c51e24431188 ]---
[  106.311591] RTL8723BS: ap recv disassoc reason code(8) sta:b8:ee:65:33:39:bf

I found potential similar posts on this forum but they were marked as addressed/patched/resolved. Do I somehow have an older nl80211 driver?

Igor · March 28, 2021

28 minutes ago, prcarp said:

I found potential similar posts on this forum but they were marked as addressed/patched/resolved. Do I somehow have an older nl80211 driver?

You mean this? If solution is found on forum, it's not necessary that fix found the way into the kernel. Start this way:

prcarp · March 28, 2021

Thanks, Igor. That looks like the situation I am in. Sorry I missed that post or I would have tried that first.

I will post a follow-up if this works or not.

prcarp · March 28, 2021

Hi Igor,

I updated my VirtualBox, downloaded the Ubuntu 20.04 image (mini.os via the link), and installed that. I also installed git (as well as gcc, make, and perl to make VirtualBox additions happy) and then did the git command to get all the build stuff.

To test things out (before I apply any modifications or changes), I ran compile.sh from the build directory (logged in as root), selected to build UBoot and the Kernel and then opted for the Armbian kernel configuration for the Tinkerboard. The script did its magic and did a lot of pulling and installing packages from the web. It then looked like it was about to compile stuff and that's when things went sideways. The error that came up is fit_image.c:19:10 fatal error: libfdt.h: No such file or directory. The #include file on this C file was not found and so the compilation terminated. The script then exited completely.

So, two questions:

1. Should I really be building the Linux kernel or can I just build the nl80211 driver somehow? I chose to do the kernel just for version consistency but perhaps this is overkill?

2. If I just build the driver, what is the best mechanism for installing it? I am not that familiar with insmod if that the route to take.

Thanks,

Paul

Igor · March 28, 2021

31 minutes ago, prcarp said:

So, two questions:

1. Should I really be building the Linux kernel or can I just build the nl80211 driver somehow? I chose to do the kernel just for version consistency but perhaps this is overkill?

2. If I just build the driver, what is the best mechanism for installing it? I am not that familiar with insmod if that the route to take.

This is "as is" community support, not a professional support service that will help their customers solve their generic problem - welcome to become a part of it by helping others or project that makes your need possible. Asus forgot about you and me long time ago.

https://forum.armbian.com/forum/54-help-wanted/
https://github.com/armbian/build#support

https://forum.armbian.com/subscriptions/

3. Install

apt install libfdt-dev

and try again.

https://forum.armbian.com/clients/donations/

prcarp · March 28, 2021

Thanks, Igor. As much as I would like to contribute software-wise, my Linux skills are a grade B at best. So I went the donation route and you should see a PayPal note from Virginia, USA.

(Kernel is compiling now...)

Igor · March 28, 2021

3 minutes ago, prcarp said:

Kernel is compiling now

I didn't check - it was just a hunch. So this library is indeed missing? We need to add it to the dependencies then. I'll cover that.

4 minutes ago, prcarp said:

As much as I would like to contribute software-wise, my Linux skills are a grade B at best. So I went the donation route and you should see a PayPal note from Virginia, USA.

To ask questions you did, one must have some clue about. What I can see on this forum, which I am often around, I see that many users needs a crutch for much easier problems. And a lot of them are just too lazy to do some minimal searching ... which can easily raise the blood pressure

But thanks anyway.