gnome-shell on 20.10 crashes all the time

[Tessa]

this is probably a dupe of a bunch of other gnome-shell crashing bugs. just noting that since upgrading to 20.10, both my systems (which use the nvidia binary X drivers) have gnome-shell crashing multiple times a day. it restarts fine, but while it's crashing it locks up the whole system for a minute or two. no idea why the release in 20.10 is so much more unstable than 20.04, but here we are.

as a starting point, how do I track down what it considers the cause of the crashes? I can't discern anything particularly useful from `journalctl` at first glance. is there a specific error message I can search for in all the noise to find where it crashed and see what happened right before that? I see a lot of these in the logs, but they seem to be non-fatal, and they also don't print out any actual stack traces to examine:

Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==
Nov 28 22:07:16 boxxy gnome-shell[222384]: == Stack trace for context 0x55995401f220 ==

ProblemType: Bug
DistroRelease: Ubuntu 20.10
Package: gnome-shell 3.38.1-1ubuntu1.1
ProcVersionSignature: Ubuntu 5.8.0-29.31-lowlatency 5.8.14
Uname: Linux 5.8.0-29-lowlatency x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu50.2
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Sat Nov 28 22:11:09 2020
DisplayManager: gdm3
InstallationDate: Installed on 2020-07-15 (137 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
RelatedPackageVersions: mutter-common 3.38.1-1ubuntu1
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to groovy on 2020-10-24 (36 days ago)

[Chris Guiver (guiverc)]

Thank you for taking the time to report this bug and helping to make Ubuntu better.

Bug reporting is mostly about finding & fixing problems thus preventing future users from hitting the same bug.

If you want a support site ("how do I track down..") you can use https://answers.launchpad.net/ubuntu. You can also find help with your problem in the support forum of your local Ubuntu community http://loco.ubuntu.com/ or asking at https://askubuntu.com or https://ubuntuforums.org, or for more support options please look at https://discourse.ubuntu.com/t/community-support/709

[Daniel van Vugt (vanvugt)]

Since so many bugs are caused by extensions, the first thing you should try is removing these:

'<email address hidden>', '<email address hidden>', '<email address hidden>', '<email address hidden>', '<email address hidden>', '<email address hidden>', '<email address hidden>', 'notification-center@Selenium-H', '<email address hidden>', '<email address hidden>', '<email address hidden>'

but also...

Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:

1. Look in /var/crash for crash files and if found run:
    ubuntu-bug YOURFILE.crash
Then tell us the ID of the newly-created bug.

2. If step 1 failed then look at https://errors.ubuntu.com/user/ID where ID is the content of file /var/lib/whoopsie/whoopsie-id on the machine. Do you find any links to recent problems on that page? If so then please send the links to us.

3. If step 2 also failed then apply the workaround from bug 994921, reboot, reproduce the crash, and retry step 1.

Please take care to avoid attaching .crash files to bugs as we are unable to process them as file attachments. It would also be a security risk for yourself.

[Tessa (unit3)]

hey Daniel,

if I'm reading the first part of your reply right, it sounds like gnome-shell extensions can hard crash gnome-shell? which means it's not safe to ever use any extensions? i feel like i must be misunderstanding that, since ubuntu distributes a set of extensions by default in the desktop env, and that wouldn't make sense if the shell extensions are so dangerous.

on to the next steps, there's no crash files in that dir, but there are files called `_usr_bin_gnome-shell.1000.upload` and `_usr_bin_gnome-shell.1000.uploaded`. I'm assuming that's what ties into errors.ubuntu.com.

I see a ton of errors around gnome on that site for my whoopsie-id, lots of gnome-shell and gnome-settings-daemon crashes:
https://errors.ubuntu.com/user/3e155148c8cdcde9fe5cd5283283ef9837d7582a978ff3ce587c63aefe0cd3d3bc1bbe4921b8fff669e75ac4de5f3962de964e0df2f56142604e65bb3aa47f5c

it doesn't let me look at those crash reports so I don't really have a clue what the root cause could be, but hopefully you have access to them and can investigate further.

[Tessa (unit3)]

it's also worth noting that my laptop, which is also seeing a bunch of these crashes on gnome-shell, doesn't have any extra extensions installed that don't come from Ubuntu. this may be coincidence, but it does feel off that after upgrading to 20.10 both my systems that run Ubuntu on the desktop have a ton of gnome-shell crashes.

[Daniel van Vugt (vanvugt)]

Thanks. That link shows all your recent gnome-shell crashes are the same; bug 1872461. So to avoid gnome-shell crashing you should just need to uninstall the one extension: 'sound-output-device-chooser'.

If you experience any other problems then please don't hesitate to open new bugs.

[Tessa (unit3)]

just had another crash, with all the extensions disabled. I tried running ubuntu-bug on the crash file, but it didn't give me a bug to link in here, not sure why. the error it reported is:

"gnome-shell crashed with signal 5 in meta_window_actor_thaw()"

[Daniel van Vugt (vanvugt)]

That's easy, and a common one. It's bug 1897765 which I am trying to get a fix released for ASAP.

[Tessa (unit3)]

had another crash immediately after. seems like the primary trigger is playing games in steam, especially games using the proton runtime layer for running windows games. so it seems like something's perhaps changed since 20.04 and now gnome-shell is intolerant of high performance vulkan applications.

[Tessa (unit3)]

and this is all after uninstalling the sound-output-device-chooser extension, so I feel like that's a bit of a red herring for my actual issue.

[Tessa (unit3)]

awesome, glad to hear it.

[Daniel van Vugt (vanvugt)]

Yes bug 1897765 relates to window resizing and going fullscreen. So a lot of gamers have been reporting it.