Gnome Shell crashes randomly

[John Steeves]

When using Ubuntu Gnome 16.04, it is common for gnome-shell to crash unexpectedly, especially when performing intensive tasks.

I've found that I was able to replicate the error by following these steps:
Download and install a copy of Ubuntu Gnome 16.04.2 in VirtualBox.
Open a screen displaying App icons in a menu, such as the app grid in the Gnome Shell overlay or the Arc Menu Gnome Shell extension (https://extensions.gnome.org/extension/1228/arc-menu/).
Install all the latest software updates from the Software Updater or Synaptic.
Upgrading all the packages between 16.04.2 to 16.04.3 seems to over-load Gnome Shell and cause the crash in the middle of the installation process.
This crash always seems to occur after opening a screen with app icons and I'm not sure why.

I've attached my .crash file updated with a symbolic stack trace.I hope this info and my attachment proves helpful in fixing the issue.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gnome-shell 3.18.5-0ubuntu0.3
ProcVersionSignature: Ubuntu 4.10.0-33.37~16.04.1-generic 4.10.17
Uname: Linux 4.10.0-33-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.10
Architecture: amd64
CurrentDesktop: GNOME
Date: Fri Sep 8 19:24:22 2017
DisplayManager: gdm3
GsettingsChanges:
 b'org.gnome.shell' b'enabled-extensions' b"['<email address hidden>']"
 b'org.gnome.shell' b'favorite-apps' b"['ubiquity.desktop', 'firefox.desktop', 'evolution.desktop', 'empathy.desktop', 'rhythmbox.desktop', 'org.gnome.Photos.desktop', 'libreoffice-writer.desktop', 'org.gnome.Nautilus.desktop', 'yelp.desktop']"
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
InstallationDate: Installed on 2017-09-08 (0 days ago)
InstallationMedia: Ubuntu-GNOME 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

Thanks for the bug report. In order to get a readable stack trace from that crash file please run this command on the machine it came from:

  ubuntu-bug _usr_bin_gnome-shell.1000.crash

That will log a new bug with the required automated analysis we need.

I have tried analysing your crash file by hand but the stack trace is not readable so we need you to resubmit it using 'ubuntu-bug'.

[John Steeves (jstevz4teh1337)]

Thanks for letting me know Daniel! I've entered this command and sent the error report less than a minute ago.

[John Steeves (jstevz4teh1337)]

I've been testing Ubuntu Gnome 16.10 and 17.04 and the same issue happens on them.
When running "gnome-shell --replace" in a Terminal before preforming the software updates, I see a "Segmentation fault (core dumped)" error in the Terminal when the crash happens.

However, the issue never appears when using the current builds of Ubuntu 17.10, both in Wayland and Xorg. Perhaps the updated GJS interpreter fixed the issue.

I still wonder if it's possible to patch the Gnome Shell package in Ubuntu 16.04 to fix this bug for the LTS users (who expect stability in their system until 2021).

[Daniel van Vugt (vanvugt)]

It looks like we won't be able to figure out the root cause of your crash until the robots can analyse and retrace it. Please let us know the new bug ID created in comment #3 if you know it.

P.S. What kind of terminal are you running "gnome-shell --replace" from? That sounds like it should be impossible, or you are using a Xorg session in which case you will have some basic windows to type in after the shell/window manager crashed.

[John Steeves (jstevz4teh1337)]

Thanks for the reply!

I'm not quite sure how to find the bug ID for the report sent in comment #3. After running the "ubuntu-bug _usr_bin_gnome-shell.1000.crash" command I saw a dialog asking to either "Examine Locally" or "Continue", the latter of which I clicked (with the "Send error report" checkbox marked). Nothing appeared on my screen after clicking "Continue" to give me a report ID. Did I do something wrong when reporting the bug?

I ran "gnome-shell --replace" from the standard Gnome Terminal (Ctrl+Alt+T) immediately before running the Software Updater, and the "Segmentation Fault" error showed up in the Terminal window beside the Software Updater window at the time of the crash. As the errors only appeared in 16.04, 16.10 and 17.04 (which don't have Wayland) I was using Xorg in these cases.

[Daniel van Vugt (vanvugt)]

Sometimes crash reports don't work reliably. I can confirm it failed to log a new bug for you:
  https://bugs.launchpad.net/~jstevz4teh1337/+reportedbugs?orderby=-id&start=0

Of course, you shouldn't be running 'gnome-shell --replace' normally unless it's already crashed beforehand. Had it crashed before you ran that command? Even still, it sounds like a dangerous way to restart the shell because the act of it restarting might kill your terminal which is now the parent of the shell. So restarting the shell like that could make it crash immediately, unless you also do:

  nohup gnome-shell --replace &

Please answer the question in the previous paragraph and also try the above more correct command instead.

[John Steeves (jstevz4teh1337)]

The crash occurs (during the software updates) regardless of whether I run the "gnome-shell --replace" command. I was only running the command before installing the software updates (and therefore, before the crash happened) in one specific session per Ubuntu release in order to get debug information when the crash happens (above). I would never run it in a normal scenario.

I crashed gnome-shell on Ubuntu 16.04 again (without running the "gnome-shell --replace" command) and added a symbolic stacktrace, which I managed to upload to Launchpad using the ubuntu-bug command (I needed to enable Apport in 16.04 LTS by commenting-out a line in /etc/apport/crashdb.conf). You can find it as a private bug report at LP: 1718268

[Daniel van Vugt (vanvugt)]

Thanks. Looks like a duplicate of bug 1706203.

[John Steeves (jstevz4teh1337)]

Thanks Daniel! Please let me know if there's anything I can do to help accelerate the bug fixing process.

[Alessandro Albanese (alessandroalb2)]

I have same problem on my ubuntu 16.04-3 64 bit box.
Crash are randomly during my work, no special operation i do before crash.
Crash appeared only last 2 months.
Before no problem.
Can give some other info or not important ?