python / pyusb / libusb

[Hans Petter Selasky]

On 12/18/20 8:42 PM, Tomasz CEDRO wrote:
> Hello world :-)
> 
> Was there any substantial change in LibUSB / USB implementation in
> FreeBSD stacks? I mean somewhere around 12.1 -> 12.2 upgrade?
> 
> I have this nice pyOCD hardware debug utility that I use for embedded
> systems debug for my everyday work. It started to segfault Python. All
> of its versions even those older ones that worked fine before. So far
> I could flash firmwares using other channel (UMS mass storage function
> of the debug probe and it works fine), but I am getting to a point
> where I need to debug target and it seems blocked for now. I also
> reported this issue to the application tracker, but it may as well
> look as problem on the OS side.
> 
> This is strange because for instance Yubikey that uses the same Python
> environment works fine.
> 
> I have used hardfault module to backtrack Python crash :-)
> 
> (venv37zephyr) pyocd list
> Fatal Python error: Segmentation fault
> 
> Current thread 0x0000000800a3a000 (most recent call first):
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/usb/backend/libusb1.py",
> line 611 in __init__
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/usb/backend/libusb1.py",
> line 644 in __iter__
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/usb/core.py",
> line 1280 in device_iter
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/probe/pydapaccess/interface/pyusb_v2_backend.py",
> line 184 in get_all_connected_interfaces
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/probe/pydapaccess/dap_access_cmsis_dap.py",
> line 68 in _get_interfaces
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/probe/pydapaccess/dap_access_cmsis_dap.py",
> line 471 in get_connected_devices
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/probe/cmsis_dap_probe.py",
> line 73 in get_all_connected_probes
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/probe/aggregator.py",
> line 64 in get_all_connected_probes
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/core/helpers.py",
> line 82 in get_all_connected_probes
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/core/helpers.py",
> line 109 in list_connected_probes
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/__main__.py",
> line 462 in do_list
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/__main__.py",
> line 402 in run
>    File "/home/cd/usr/local/venv37zephyr/lib/python3.7/site-packages/pyocd-0.28.1.dev97+dirty-py3.7.egg/pyocd/__main__.py",
> line 931 in main
>    File "/home/cd/usr/local/venv37zephyr/bin/pyocd", line 11 in <module>
> Segmentation fault
> 
> Any hints welcome :-)

Maybe a ktrace / kdump will get you more hints.

--HPS