Upload hanging or Device or Resource Busy on Linux

[kusti8]

Expected Behavior:

For pros to upload the project to the v5 brain.

Actual Behavior:

Sometimes, I get a Device or Resource Busy message or the upload just hangs at some random percentage and won't continue. Sometimes running udevadm trigger and unplugging and replugging works, but other times it just hangs.

I am part of the dialout group and this only happens occasionally. If I spin up a Windows VM right after it hangs, and connect that to the USB device, then the upload works without issue. If I reboot and try again, the problem persists.

Steps to reproduce:

1. Plug in brain and try to upload with pros v5 u.

System information:

Operating System: Ubuntu

PROS Version: 3.1.3

Additional Information

Screenshots/Output Dumps/Stack Traces

make: Nothing to be done for 'quick'.
Uploading bin/output.bin to v5 device on /dev/ttyACM0 as States to slot 1
ERROR - pros.cli.upload:upload - [Errno 16] could not open port /dev/ttyACM0: [Errno 16] Device or resource busy: '/dev/ttyACM0'
  File "/home/kusti8/.local/lib/python3.6/site-packages/serial/serialposix.py", line 268, in open
    raise SerialException(msg.errno, "could not open port {}: {}".format(self._port, msg))
serial.serialutil.SerialException: [Errno 16] could not open port /dev/ttyACM0: [Errno 16] Device or resource busy: '/dev/ttyACM0'

After running udevadm trigger and replugging the wire, it hangs

make: Nothing to be done for 'quick'.
Uploading bin/output.bin to v5 device on /dev/ttyACM0 as States to slot 1
Uploading slot_1.ini [####################################] 100%
Uploading slot_1.bin (bin/output.bin) [##########--------------------------]  27%

[HotelCalifornia]

closing as a duplicate of #45

[kusti8]

I saw the other issue, however mine seems to be slightly different. Mine hangs midway through downloading, and I do have permissions, and there are no other processes that are running as far as I can tell (I ran lsof and tried to kill any other python scripts).

[edjubuh]

Can you run prosv5 u --debug > debug.output.txt and share it via gist or pastebin or upload file?

[kusti8]

https://pastebin.com/Kack4rrN

https://pastebin.com/2NgwJYSt

[edjubuh]

🤔 you're on the develop branch now (instead of 3.1.3)? Just making sure we're on the same page

[kusti8]

I switched to the wireless upload branch to test that out, but the issue was the same on the master branch and the develop branch.

[edjubuh]

I might be able to patch something for this log, but I'm still not sure why it failed half-way through as you originally posted since the log you attached shows it failed at an earlier stage.

[edjubuh]

I've created a branch: hotfix/kusti8-debugging that has a potential patch for the log you sent.

[kusti8]

The point at which it fails is different every time, usually stopping earlier every time. I'll try out the fix, thanks.

[edjubuh]

I noticed you ctrl+c'd it out. You did say it was hanging, which is odd because we set timeout to something like 1 second with 3 retries of the same command, so it should never hang for more 3-ish seconds. I assume it hangs for 10+ seconds?

[kusti8]

Yeah it hangs for 10+ seconds. I had to Ctrl+c it.

[kusti8]

Hi, the patch prevents it from hanging. It still says device or resource busy, so I have to run udevadm trigger 1 or 2 times, but it works consistently after that.

[edjubuh]

Glad to hear it works. I'll close this issue for now unless you can determine a consistent workflow that causes the "device or resource busy" error. We'd probably have to report that to upstream pyserial.