Can't connect to old devices (iOS 12), device reboot after unplugging

[hiepnh0]

• Plug in device
  syslog:

Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.771][3] usbmuxd v1.1.0-158-gf1f8d58 starting up
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.772][3] Successfully dropped privileges to 'usbmux'
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.772][3] Using libusb 1.0.20
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.774][3] Initialization complete
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.774][3] Enabled exit on SIGUSR1 if no devices are attached. Start a new instance with "--exit" to trigger.
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.775][2] Switching device 1-26 mode to 3
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.778][2] Cannot find device entry while removing USB device 0x6dfeb0 on location 0x1001a
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.778][2] Cannot find device entry while removing USB device 0x6dfeb0 on location 0x1001a
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.780][3] usbmuxd shutting down
Oct 31 09:27:35 hiep-Vostro-3668 usbmuxd[15371]: [09:27:35.881][3] Shutdown complete
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.399][3] usbmuxd v1.1.0-158-gf1f8d58 starting up
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.405][3] Successfully dropped privileges to 'usbmux'
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.414][3] Using libusb 1.0.20
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.426][3] Initialization complete
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.426][3] Enabled exit on SIGUSR1 if no devices are attached. Start a new instance with "--exit" to trigger.
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.426][3] Found CDC-NCM and Apple USB Multiplexor in device 1-27 configuration 5
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.426][2] Skipping switch device 1-27 mode from 3 to 3
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: libusb: error [op_get_configuration] device unconfigured
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.426][3] Found usbmux interface for device 1-27: 1
Oct 31 09:27:36 hiep-Vostro-3668 usbmuxd[15407]: [09:27:36.426][3] Changing configuration of device 1-27: 0 -> 5
Oct 31 09:28:38 hiep-Vostro-3668 usbmuxd[15407]: [09:28:38.885][1] Failed to request lang ID for device 1-27 (2)

• Unplug device
  syslog:

Oct 31 09:29:27 hiep-Vostro-3668 usbmuxd[15407]: [09:29:27.968][2] Cannot find device entry while removing USB device 0xeeb0f0 on location 0x1001b
Oct 31 09:29:27 hiep-Vostro-3668 usbmuxd[15407]: [09:29:27.968][2] Cannot find device entry while removing USB device 0xeeb0f0 on location 0x1001b
Oct 31 09:29:27 hiep-Vostro-3668 usbmuxd[15407]: [09:29:27.985][3] usbmuxd shutting down
Oct 31 09:29:28 hiep-Vostro-3668 usbmuxd[15407]: [09:29:28.086][3] Shutdown complete

$usbmuxd --version
usbmuxd 1.1.0-158-gf1f8d58

iPhone 6
iOS 12.5.7

Ubuntu 16.04 LTS

iPhone 7 Plus, iOS 15.8 is OK

[IsanHu]

Hello, is there any progress on this issue?

[httpstorm]

Mode 3 breaks tethering for me. Reverting to mode 1 makes it work again. Here is my research c7a0dd9#r141306029

@nikias @FunkyM @BalkanMadman @rickmark @Blefish @marcan

[nikias]

@httpstorm Thanks for pointing this out, looks like the CDC NCM support in ipheth would be good enough to default this back to mode 1. I was looking to add a way to dynamically allow mode switching on demand, but haven't completed my work on that yet.

[httpstorm]

@nikias
Thanks for the quick replay. Are you able to enable tethering in mode 3 and how?

• The benefit of mode 1 is that we only need ipheth so the interface will always be named eth0 when we switch between old and new iPhones. With mode 3 we would need configurations for both eth0 and usb0.
• The con of mode 1 is slower performance. This could be addressed by optimising ipheth.

I will make a PR to update all libimobiledevice in OpenWRT shortly. The latest release for some of the packages is 2020-06-16 and it does not compile unless we move forward, so I switched them to the latest commit.

I was looking to add a way to dynamically allow mode switching on demand, but haven't completed my work on that yet.

If you come up with interesting ideas, I can help you test them.
Can you please have a look at #218 ? We addressed it here openwrt/packages#23976
It would be nice if you can fix it in usbmuxd.