System hangs after attaching Mediatek mt76x2u based USB Wifi network adapter

[Joerg Leonhard]

After attaching a Mediatek mt76x2u based USB Wifi network adapter the system (Ubuntu 20.04.1 LTS linux version 5.4.0-58-generic) hangs

My findings after some testing:
- A freshly installed Ubuntu 20.04 (for testing purposes) with an outdated kernel 5.4.0-26 is not affected as the USB Wifi network adapter works without any problems.
- After updating this system to kernel version 5.4.0-58 the problem can be reproduced.
- After upgrading to Ubuntu 20.10 with kernel version 5.8.0-33 the USB Wifi network adapter works without any problems.
So I guess it could be a software problem (maybe linux-image oder linux-modules?).
---
ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu27.14
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: joerg 821 F.... pulseaudio
CasperMD5CheckResult: skip
DistroRelease: Ubuntu 20.04
InstallationDate: Installed on 2020-03-14 (291 days ago)
InstallationMedia: Xubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017)
IwConfig:
 enp0s25 no wireless extensions.

 lo no wireless extensions.
MachineType: FUJITSU ESPRIMO P7936
NonfreeKernelModules: nvidia
Package: linux (not installed)
ProcEnviron:
 LANGUAGE=de_DE
 TERM=xterm-256color
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
ProcFB:

ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-58-generic root=UUID=62b871bf-f08a-4cd3-90a5-d6e3d83c7e9c ro quiet splash
ProcVersionSignature: Ubuntu 5.4.0-58.64-generic 5.4.73
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon.
RelatedPackageVersions:
 linux-restricted-modules-5.4.0-58-generic N/A
 linux-backports-modules-5.4.0-58-generic N/A
 linux-firmware 1.187.6
RfKill:

Tags: focal
Uname: Linux 5.4.0-58-generic x86_64
UpgradeStatus: Upgraded to focal on 2020-12-27 (2 days ago)
UserGroups: N/A
_MarkForUpload: True
dmi.bios.date: 04/21/2011
dmi.bios.vendor: FUJITSU // Phoenix Technologies Ltd.
dmi.bios.version: 6.00 R1.06.3012.A1
dmi.board.name: D3012-A1
dmi.board.vendor: FUJITSU
dmi.board.version: S26361-D3012-A1
dmi.chassis.type: 6
dmi.chassis.vendor: FUJITSU
dmi.chassis.version: C$PIP1
dmi.modalias: dmi:bvnFUJITSU//PhoenixTechnologiesLtd.:bvr6.00R1.06.3012.A1:bd04/21/2011:svnFUJITSU:pnESPRIMOP7936:pvr:rvnFUJITSU:rnD3012-A1:rvrS26361-D3012-A1:cvnFUJITSU:ct6:cvrC$PIP1:
dmi.product.name: ESPRIMO P7936
dmi.sys.vendor: FUJITSU

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1909474/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1909474

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

apport information

[Joerg Leonhard (jleonhard)]

"apport-collect" was executed without the USB Mediatek Wifi adapter as the network does not work, when it's plugged in :-(

[Vital Koshalew (vital-0)]

I can add that kernel 5.4.0-52-generic is NOT affected so the bug was introduced between 5.4.0-53 and 5.4.0-58.

[Joerg Leonhard (jleonhard)]

I just checked: I cannot reproduce the effect with linux-image-5.4.0-173-generic, i.e. the mentioned problem seems to have been silently fixed.