Driver seems to cause a freeze on RPi 1

[thr-4]

Hi, I am aware the readme mentions that the driver isn't tested for "ARMv7 32-bit, single-core", but I was happily using it on my RPi 1 for months with no issues whatsoever. After a recent update of either kernel to Linux 6.18.39 or the driver to the "patched.9" version, the driver seems to have stopped working, with the Raspberry Pi hanging after boot.

Is there any possible known issue that might have caused this? The ./test.sh script passes successfully.

Thanks!

[thr-4]

Aug 12 08:49:12 thr-dietpi kernel: usb 1-1.3: new high-speed USB device number 5 using dwc_otg
Aug 12 08:49:12 thr-dietpi kernel: usb 1-1.3: New USB device found, idVendor=3625, idProduct=0110, bcdDevice= 1.00
Aug 12 08:49:12 thr-dietpi kernel: usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Aug 12 08:49:12 thr-dietpi kernel: usb 1-1.3: Product: AIC8800DC
Aug 12 08:49:12 thr-dietpi kernel: usb 1-1.3: Manufacturer: AICSemi
Aug 12 08:49:12 thr-dietpi kernel: usb 1-1.3: SerialNumber: 20220127
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        Number of interfaces: 1 not supported
Aug 12 08:49:13 thr-dietpi kernel: 8800dw
Aug 12 08:49:13 thr-dietpi kernel: [0x40500010]=e
Aug 12 08:49:13 thr-dietpi kernel: patch 1101a0 = 20010
Aug 12 08:49:13 thr-dietpi kernel: patch 11022c = 13fc00
Aug 12 08:49:13 thr-dietpi kernel: patch 11024c = ad180100
Aug 12 08:49:13 thr-dietpi kernel: patch 110220 = 40
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110888  180e4d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1108ec  185bb9
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110874  180e8d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110658  18171d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1107dc  1817ad
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1107e0  181ac1
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1107b8  181b25
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110838  181e71
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110490  183755
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110420  182aa5
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  11089c  184d4d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  11048c  182bc1
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110688  182d4d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110738  183689
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110554  18395d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  11085c  183ebd
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1108c4  1844c9
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1108c8  184099
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110628  1846e1
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110898  184885
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1103d0  186285
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110518  184a89
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1105e0  185b01
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1106c8  186a8d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110054  18171d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  11005c  18171d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110048  183755
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110bb4  182779
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  1109c0  1820d5
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110f08  182a85
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110b5c  182e61
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110b64  182e61
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110b6c  182e61
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110b74  182e61
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110b7c  182e61
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110b8c  182e61
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110ac0  185f79
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110aa0  183e6d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110c40  184b91
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110bf8  184e35
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110a70  18678d
Aug 12 08:49:13 thr-dietpi kernel: AICWFDBG(LOGERROR)        patch_tbl:  110ef0  1868e5
Aug 12 08:49:13 thr-dietpi kernel: ieee80211 phy0:
                                   *******************************************************
                                   ** CAUTION: USING PERMISSIVE CUSTOM REGULATORY RULES **
                                   *******************************************************

[thr-4]

Aug 12 08:52:28 thr-dietpi kernel: Exception stack(0xdc871fb0 to 0xdc871ff8)
Aug 12 08:52:28 thr-dietpi kernel: 1fa0:                                     00000000 00000000 00000000 00000000
Aug 12 08:52:28 thr-dietpi kernel: 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
Aug 12 08:52:28 thr-dietpi kernel: 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
Aug 12 08:52:28 thr-dietpi kernel: INFO: task kworker/u4:1:19 is blocked on a mutex likely owned by task kworker/0:2:35.
Aug 12 08:52:28 thr-dietpi kernel: INFO: task kworker/0:2:35 blocked for more than 122 seconds.
Aug 12 08:52:28 thr-dietpi kernel:       Tainted: G         C O        6.18.39+rpt-rpi-v6 #1 Raspbian 1:6.18.39-1+rpt1
Aug 12 08:52:28 thr-dietpi kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Aug 12 08:52:28 thr-dietpi kernel: task:kworker/0:2     state:D stack:0     pid:35    tgid:35    ppid:2      task_flags:0x4288060 flags:0x00000000
Aug 12 08:52:28 thr-dietpi kernel: Workqueue: usb_hub_wq hub_event
Aug 12 08:52:28 thr-dietpi kernel: Call trace:
Aug 12 08:52:28 thr-dietpi kernel:  __schedule from schedule+0x28/0xec
Aug 12 08:52:28 thr-dietpi kernel:  schedule from schedule_preempt_disabled+0x14/0x18
Aug 12 08:52:28 thr-dietpi kernel:  schedule_preempt_disabled from __mutex_lock.constprop.0+0x3cc/0x8f0
Aug 12 08:52:28 thr-dietpi kernel:  __mutex_lock.constprop.0 from cfg80211_netdev_notifier_call+0x25c/0x460 [cfg80211]
Aug 12 08:52:28 thr-dietpi kernel:  cfg80211_netdev_notifier_call [cfg80211] from notifier_call_chain+0x54/0xcc
Aug 12 08:52:28 thr-dietpi kernel:  notifier_call_chain from raw_notifier_call_chain+0x20/0x28
Aug 12 08:52:28 thr-dietpi kernel:  raw_notifier_call_chain from __dev_close_many+0x64/0x218
Aug 12 08:52:28 thr-dietpi kernel:  __dev_close_many from netif_close_many+0x84/0x128
Aug 12 08:52:28 thr-dietpi kernel:  netif_close_many from unregister_netdevice_many_notify+0x220/0x9ac
Aug 12 08:52:28 thr-dietpi kernel:  unregister_netdevice_many_notify from unregister_netdevice_queue+0xac/0xf8
Aug 12 08:52:28 thr-dietpi kernel:  unregister_netdevice_queue from _cfg80211_unregister_wdev+0x1e4/0x274 [cfg80211]
Aug 12 08:52:28 thr-dietpi kernel:  _cfg80211_unregister_wdev [cfg80211] from rwnx_cfg80211_del_iface+0x13c/0x17c [aic8800_fdrv]
Aug 12 08:52:28 thr-dietpi kernel:  rwnx_cfg80211_del_iface [aic8800_fdrv] from rwnx_cfg80211_deinit+0xac/0x170 [aic8800_fdrv]
Aug 12 08:52:28 thr-dietpi kernel:  rwnx_cfg80211_deinit [aic8800_fdrv] from aicwf_bus_deinit+0xd4/0x13c [aic8800_fdrv]
Aug 12 08:52:28 thr-dietpi kernel:  aicwf_bus_deinit [aic8800_fdrv] from aicwf_usb_disconnect+0x44/0x10c [aic8800_fdrv]
Aug 12 08:52:28 thr-dietpi kernel:  aicwf_usb_disconnect [aic8800_fdrv] from usb_unbind_interface+0x7c/0x298
Aug 12 08:52:28 thr-dietpi kernel:  usb_unbind_interface from device_release_driver_internal+0x180/0x1f0
Aug 12 08:52:28 thr-dietpi kernel:  device_release_driver_internal from bus_remove_device+0xe4/0x178
Aug 12 08:52:28 thr-dietpi kernel:  bus_remove_device from device_del+0x148/0x44c
Aug 12 08:52:28 thr-dietpi kernel:  device_del from usb_disable_device+0xcc/0x178
Aug 12 08:52:28 thr-dietpi kernel:  usb_disable_device from usb_disconnect+0xd8/0x26c
Aug 12 08:52:28 thr-dietpi kernel:  usb_disconnect from usb_disconnect+0xbc/0x26c
Aug 12 08:52:28 thr-dietpi kernel:  usb_disconnect from hub_event+0x768/0x1610
Aug 12 08:52:28 thr-dietpi kernel:  hub_event from process_one_work+0x138/0x34c
Aug 12 08:52:28 thr-dietpi kernel:  process_one_work from worker_thread+0x170/0x30c
Aug 12 08:52:28 thr-dietpi kernel:  worker_thread from kthread+0x108/0x250
Aug 12 08:52:28 thr-dietpi kernel:  kthread from ret_from_fork+0x14/0x28
Aug 12 08:52:28 thr-dietpi kernel: Exception stack(0xdc8b1fb0 to 0xdc8b1ff8)

[Kiborgik]

Thanks for reporting! That second trace pins it, and patched.9 has nothing to do with it. The hang is in the driver teardown path.

When the stick disappears, aicwf_usb_disconnect runs rwnx_cfg80211_deinit, which holds rtnl plus wiphy->mtx while rwnx_cfg80211_del_iface calls cfg80211_unregister_wdev(). That unregisters the netdev, and since wlan0 was still up the netdev has to be closed first, so cfg80211s notifier goes for wiphy->mtx a second time on NETDEV_GOING_DOWN. hub_event ends up in __mutex_lock with rtnl still held, the next worker piles up behind it, and the board is gone.

I added that lock in patched.3 to fix a different deadlock, the one iwd triggers when it resets wlan0 through nl80211. wdev->registered short-circuits NETDEV_UNREGISTER only, not the close path, so every version from patched.3 onwards has this in it. What it needs is the interface being up at the moment the device vanishes, and a reboot or rmmod brings it down first, which is why months of normal use never tripped it.

On the version question: between patched.8 and .9 the driver code lost three unused variables, gained one static, and got a Mercusys MA14N (2c4e:0114) special case. Your stick is 3625:0110 and takes the same path it always did, so there is nothing useful to roll back to. Number of interfaces: 1 not supported and 8800dw are normal for your stick, they are not the failure.

What I cannot explain from here is why the port went away in the first place. At 08:52, three minutes into the boot, usb_disconnect from usb_disconnect under hub_event means the whole port dropped, not just our interface. On an RPi 1 that is usually 5V or the hub re-enumerating. Worth looking at separately, but the freeze is ours either way.

Fix is #23, merged to main: close the netdevs before taking wiphy->mtx, the way mac80211 does it in ieee80211_remove_interfaces() via cfg80211_shutdown_all_interfaces(). Guarded to 5.12+, so older kernels are untouched. It builds across the CI matrix but the deadlock needs your hardware, so a result from your Pi would help a lot.

cd <your checkout>
./update.sh        # no sudo, it pulls and re-runs install.sh
sudo ./test.sh

The DKMS version string is still 6.4.3.0-patched.9 because I bump that on release rather than per fix, so to be sure the new code landed:

grep -c cfg80211_shutdown_all_interfaces /usr/src/aic8800dc-6.4.3.0-patched.9/drivers/aic8800/aic8800_fdrv/rwnx_main.c

should print 1.

You can also provoke it on demand rather than waiting for the next disconnect. With wlan0 up and connected, sudo modprobe -r aic8800_fdrv hangs the same way your trace does and needs a hard reset; with the fix it should return immediately. Bring wlan0 down first and it always worked, and that difference is what confirms the diagnosis. If you would rather not risk a hang, just run it normally for a few days and say whether the freeze comes back.

If it does come back, these would help:

• sudo journalctl -k -b -1 --no-pager > aic-hang.txt after the hang, so the whole previous boot. The kworker/u4:1:19 trace is cut off in your paste and it is the other half of the lock cycle.
• ip -br link, iw dev, and systemctl is-active wpa_supplicant iwd NetworkManager systemd-networkd, to confirm wlan0 was up when the disconnect landed.
• dkms status and ls /lib/modules. If the kernel you ran before 6.18.39 still boots, that separates the kernel change from the driver change.
• vcgencmd get_throttled and any over-current or reset lines in dmesg, for the disconnect itself.