Ubuntu Focal Fossa freezes spontaneously -- must power off when this happens

[Bill Yikes]

I just did a fresh first-time install of Ubuntu on a Dell Inspirion 14 with no modifications apart from installing Canon printer drivers and no 3rd party peripherals. The desktop freezes spontaneously. When it freezes, the display freezes including the mouse pointer, and all keystrokes are unresponsive (can't even do ctrl-alt-F3 to get a tty). Forced power off is the only possible action.

I think this is irrelevent, but I'll mention that (I think) the lockup only happens when I'm using VLC to play MythTV-served videos from the LAN. Nothing else is running.. not even a browser. I'm simply watching a video and out of the blue it hangs. After rebooting, I play the same video I was watching just before the hang, and finish watching without a freeze up. Which means there's no relation to the video data.

$ inxi -Fxz
System: Kernel: 5.4.0-42-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 Desktop: Gnome 3.36.3
           Distro: Ubuntu 20.04.1 LTS (Focal Fossa)
Machine: Type: Portable System: Dell product: Inspiron 14-3452 v: 4.0.7 serial: <filter>
           Mobo: Dell model: 0625M8 v: A00 serial: <filter> UEFI: Dell v: 4.0.7 date: 04/26/2016
Battery: ID-1: BAT0 charge: 33.6 Wh condition: 33.6/41.4 Wh (81%) model: Samsung SD DELL 07G075A status: Full
CPU: Topology: Dual Core model: Intel Celeron N3050 bits: 64 type: MCP arch: Airmont rev: 3 L2 cache: 1024 KiB
           flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 6400
           Speed: 1377 MHz min/max: 480/2160 MHz Core speeds (MHz): 1: 1034 2: 1139
Graphics: Device-1: Intel Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Integrated Graphics vendor: Dell driver: i915
           v: kernel bus ID: 00:02.0
           Display: server: X.Org 1.19.2 driver: i915 resolution: 1280x800~60Hz
           OpenGL: renderer: llvmpipe (LLVM 10.0.0 128 bits) v: 3.3 Mesa 20.0.8 direct render: Yes
Audio: Device-1: Intel Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series High Definition Audio vendor: Dell
           driver: snd_hda_intel v: kernel bus ID: 00:1b.0
           Sound Server: ALSA v: k5.4.0-42-generic
Network: Device-1: Realtek RTL8723BE PCIe Wireless Network Adapter driver: rtl8723be v: kernel port: e000 bus ID: 01:00.0
           IF: wlp1s0 state: up mac: <filter>
Drives: Local Storage: total: 29.12 GiB used: 8.75 GiB (30.0%)
           ID-1: /dev/mmcblk0 model: HBG4e size: 29.12 GiB
Partition: ID-1: / size: 28.05 GiB used: 8.74 GiB (31.2%) fs: ext4 dev: /dev/mmcblk0p2
Sensors: System Temperatures: cpu: 52.0 C mobo: 47.0 C
           Fan Speeds (RPM): cpu: 3181
Info: Processes: 199 Uptime: 41m Memory: 1.85 GiB used: 891.8 MiB (46.9%) Init: systemd runlevel: 5 Compilers: gcc: N/A
           Shell: bash v: 5.0.17 inxi: 3.0.38

[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/1889992/+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 1889992

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.

[Bill Yikes (yik3s)]

The apport-collect command does not seem to give a way to save to a file, so there's no way for users to inspect the data before sending. The man page for apport-collect says "Bug reports can be written to a file by using the --save option or by using apport-cli."

The --save option is not part of the syntax, and when it's used the response is "apport-collect: error: no such option: --save". The apport-cli certainly has a --save option, but that only grabs "non-crash" telemetry.

[Kai-Heng Feng (kaihengfeng)]

Maybe just attach `journalctl -b -1` here?

[Bill Yikes (yik3s)]

Immediately after a crash and forced poweroff, I ran "journalctl -b -1", which I've pasted below (minus the huge amount of systemd-udevd logs which are likely irrelevant). The freeze always happens in VLC, and indeed the logs show VLC failures at the end of the logs.

I should also note that I'm using glitchy cheap chinese bluetooth speakers. No matter what device connects to these speakers (phones and various laptops), the sound often dies and I have to disconnect and reconnect the bluetooth session to recover. I doubt that's related but mention it for completeness.

When VLC can bring down the whole platform, that seems like a serious problem with the kernel. Regardless of how badly an app like VLC behaves, it shouldn't be able to freeze the whole system.

---

Aug 21 08:53:40 hostname kernel: microcode: microcode updated early to revision 0x368, date = 2019-04-23
Aug 21 08:53:40 hostname kernel: Linux version 5.4.0-42-generic (buildd@lgw01-amd64-038) (gcc version 9.3.0 (Ubuntu 9.3.0-10ubuntu2)) #46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 2020 (Ubuntu 5.4.0-42.46-generic 5.4.44)
Aug 21 08:53:40 hostname kernel: Command line: BOOT_IMAGE=/boot/vmlinuz-5.4.0-42-generic root=UUID=(redacted) ro quiet splash vt.handoff=7
Aug 21 08:53:40 hostname kernel: KERNEL supported cpus:
Aug 21 08:53:40 hostname kernel: Intel GenuineIntel
Aug 21 08:53:40 hostname kernel: AMD AuthenticAMD
Aug 21 08:53:40 hostname kernel: Hygon HygonGenuine
Aug 21 08:53:40 hostname kernel: Centaur CentaurHauls
Aug 21 08:53:40 hostname kernel: zhaoxin Shanghai
Aug 21 08:53:40 hostname kernel: x86/fpu: x87 FPU will use FXSAVE

(...) [copious systemd-udevd logs snipped]

Aug 21 09:19:11 hostname systemd-udevd[4206]: value '[dmi/id]sys_vendor' is 'Dell Inc.'
Aug 21 09:19:11 hostname systemd-udevd[4205]: ext4_inode_cache(357:console-setup.service): Device (SEQNUM=7613, ACTION=remove) processed
Aug 21 09:19:11 hostname systemd-udevd[4205]: ext4_inode_cache(357:console-setup.service): sd-device-monitor: Passed 164 byte to netlink monitor
Aug 21 09:19:11 hostname systemd-udevd[4206]: ext4_inode_cache(1161:NetworkManager-dispatcher.service): Device (SEQNUM=7614, ACTION=remove) processed
Aug 21 09:19:11 hostname systemd-udevd[4206]: ext4_inode_cache(1161:NetworkManager-dispatcher.service): sd-device-monitor: Passed 177 byte to netlink monitor
Aug 21 09:19:14 hostname systemd-udevd[325]: Cleanup idle workers
Aug 21 09:19:14 hostname systemd-udevd[4205]: Unload module index
Aug 21 09:19:14 hostname systemd-udevd[4205]: Unloaded link configuration context.
Aug 21 09:19:14 hostname systemd-udevd[4206]: Unload module index
Aug 21 09:19:14 hostname systemd-udevd[4206]: Unloaded link configuration context.
Aug 21 09:19:14 hostname systemd-udevd[325]: Worker [4205] exited
Aug 21 09:19:14 hostname systemd-udevd[325]: Worker [4206] exited
Aug 21 09:19:23 hostname vlc.desktop[2577]: [00005591dba78700] main audio output error: too low audio sample frequency (0)
Aug 21 09:19:23 hostname vlc.desktop[2577]: [00007fb34d0176b0] main decoder error: failed to create audio output
Aug 21 09:19:23 hostname vlc.desktop[2577]: [00007fb34c009260] ts demux error: libdvbpsi error (PSI decoder): TS d...

[Bill Yikes (yik3s)]

It locked up again. This time I let it sit there in the frozen state for ~5 minutes before powering off. It was so frozen that it did not respond to attempts to SSH in. This time the logs show more systemd-udevd logs at the end. The new logs are attached.

[Kai-Heng Feng (kaihengfeng)]

Software render is in use:
OpenGL: renderer: llvmpipe (LLVM 10.0.0 128 bits) v: 3.3 Mesa 20.0.8 direct render: Yes

And there isn't a lot free memory:
Info: Processes: 199 Uptime: 41m Memory: 1.85 GiB used: 891.8 MiB (46.9%)

[Timo Aaltonen (tjaalton)]

the real bug is why it's not using the native driver.. run apport-collect which should add relevant logs etc for mesa

[Launchpad Janitor (janitor)]

[Expired for mesa (Ubuntu) because there has been no activity for 60 days.]