usb-midi-device crashes esp32-s3 when OUT USB packets sent at line rate
Nobody has claimed this yet.
Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 65/100
- Issue type
- Bug
- Clarity
- Mostly clear
- Activity status
- Active
- Tech stack
- python
- Domain
- embedded-iot
Research direction
Reproduce the failure with midi_example.py on an ESP32-S3 using the provided rtmidi2 line-rate sender. Start by tracing the receive and transfer callbacks in usb/device/midi.py and usb/device/core.py, especially the paths shown in the traceback. Done means sustained MIDI input no longer produces Buffer attribute errors or a hard crash.
Written by the indexing model from the issue text.
Description
Splitting this issue out from #1158 where it was independently discovered by @agatti while investigating a related issue.
The issue can be reproduced by setting up a CPython program that transmits MIDI data to the device as quickly as possible. For example:
import rtmidi2
out = rtmidi2.MidiOut()
# Port 1 is 'Espressif Device:Espressif Device MIDI 1 24:0' in my case
out.open_port(1)
while True:
out.send_pitchbend(0, 0) # channel, pitch
out.send_noteon(0, 48, 100)
out.send_noteoff(0, 48)
print(".", end="")
(Note that only the second two messages are currently processed by the MIDI device class, pitchbend messages are discarded.)
If running midi_example.py on the ESP32-S3, the exhibited behaviour is a few messages may be processed normally and then the handler fails with nonsense errors such as:
Traceback (most recent call last):
File "usb/device/midi.py", line 168, in _on_rx
File "usb/device/core.py", line 859, in pend_read
AttributeError: 'Buffer' object has no attribute '_b'
Traceback (most recent call last):
File "usb/device/core.py", line 342, in _xfer_cb
File "usb/device/midi.py", line 156, in _rx_cb
File "usb/device/core.py", line 827, in finish_write
AttributeError: 'Buffer' object has no attribute '_b'
and/or possibly a hard crash.
- Dominant language
- Python
- Stars
- 2.9k
- Forks
- 1.1k
- Avg merge
- 7d 4h
- Merged PRs (30d)
- 4
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
More from micropython/micropython-lib
-
Difficulty 2/5 1-3 hours Newbie friendliness 62/100
micropython/micropython-lib#1074 ·
-
needs-info
Difficulty 1/5 Under an hour Newbie friendliness 72/100
micropython/micropython-lib#943 · 1 comment ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
micropython/micropython-lib#931 · 1 comment ·
-
Difficulty 1/5 Under an hour Newbie friendliness 62/100
micropython/micropython-lib#795 · 2 comments ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 62/100
micropython/micropython-lib#762 ·
All issues in micropython/micropython-lib
Similar issues
-
agent-ready documentation needs-triage
Difficulty 1/5 1-3 hours Newbie friendliness 88/100
-
documentation
Difficulty 1/5 Under an hour Newbie friendliness 91/100
-
workflow-status page template still says reusable workflows are "triggered only by workflow_call:" Open
Difficulty 1/5 Under an hour Newbie friendliness 92/100
-
instance instance add
Difficulty 1/5 Under an hour Newbie friendliness 72/100
searxng/searx-instances#939 · 1 comment ·
-
area-deployment area-integrations triage:bot-seen
Difficulty 2/5 Half a day Newbie friendliness 86/100