gnome-shell crashed with SIGABRT in _g_log_abort()

[Marius Gedminas]

Took laptop out of backpack, opened it, plugged in an external monitor using DisplayPort, got this apport error about a gnome-shell crash.

It looks like an assertion failure in libmutter, something to do with multi-monitor support. Probably a race condition, since it doesn't happen every time.

ProblemType: Crash
DistroRelease: Ubuntu 13.10
Package: gnome-shell 3.10.2.1-0ubuntu1~saucy1 [origin: LP-PPA-gnome3-team-gnome3]
ProcVersionSignature: Ubuntu 3.11.0-18.32-generic 3.11.10.4
Uname: Linux 3.11.0-18-generic x86_64
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: amd64
Date: Fri Feb 28 13:36:16 2014
DisplayManager: gdm
EcryptfsInUse: Yes
ExecutablePath: /usr/bin/gnome-shell
GsettingsChanges:
 b'org.gnome.desktop.interface' b'clock-show-date' b'true'
 b'org.gnome.desktop.interface' b'clock-show-seconds' b'true'
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
InstallationDate: Installed on 2012-07-25 (582 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
MarkForUpload: True
ProcCmdline: /usr/bin/gnome-shell
Signal: 6
SourcePackage: gnome-shell
StacktraceTop:
 _g_log_abort () at /build/buildd/glib2.0-2.38.2/./glib/gmessages.c:255
 g_assertion_message (domain=domain@entry=0x7f6ef344aae1 "mutter", file=file@entry=0x7f6ef344985e "core/monitor-config.c", line=line@entry=1806, func=func@entry=0x7f6ef344a020 "meta_monitor_config_assign_crtcs", message=message@entry=0x44f9420 "assertion failed: (n_outputs == config->n_outputs)") at /build/buildd/glib2.0-2.38.2/./glib/gtestutils.c:2278
 g_assertion_message_expr (domain=0x7f6ef344aae1 "mutter", file=0x7f6ef344985e "core/monitor-config.c", line=1806, func=0x7f6ef344a020 "meta_monitor_config_assign_crtcs", expr=<optimized out>) at /build/buildd/glib2.0-2.38.2/./glib/gtestutils.c:2293
 ?? () from /usr/lib/libmutter.so.0
 _g_closure_invoke_va (closure=0x2585b50, return_value=0x0, instance=0x244b960, args=0x7fff07ccbab8, n_params=0, param_types=0x0) at /build/buildd/glib2.0-2.38.2/./gobject/gclosure.c:840
Title: gnome-shell crashed with SIGABRT in _g_log_abort()
UpgradeStatus: Upgraded to saucy on 2013-10-17 (133 days ago)
UserGroups: adm cdrom dip libvirtd lpadmin plugdev sambashare sudo wireshark
gdmSessionLog:
 /etc/gdm/Xsession: Beginning session setup...
 localuser:mg being added to access control list
 localuser:mg being added to access control list
 Script for cjkv started at run_im.
 Script for default started at run_im.

[Ubuntu GNOME (ug-bot)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1285124, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.

[Tim Lunn (darkxst)]

Marius, can you try test mutter 3.10.4 (in Trusty) I think this is fixed there?

[Marius Gedminas (mgedmin)]

I've been using GNOME 3.10 on Saucy for a month (since Jan 24), and this was the first time I saw this error. I don't think a brief test with Trusty is going to definitely confirm that this has been fixed, given its rarity (and I plug/unplug my external monitor every day at work).

I cannot look at bug 1285124 (presumably it's marked private). Is it linked to an upstream bug?

I was unable to find anything mentioning "assertion failed: (n_outputs == config->n_outputs)" on bugzilla.gnome.org.

I looked at mutter commits between 3.10.1.1 and 3.10.4, and also between 3.10.1.1 and master, and I don't see anything that looks like a fix for this.

I'll file an upstream bug when I can find a spare moment.

The severity of this bug is low: when gnome-shell crashes, it's immediately restarted. The only user-visible thing is that apport dialog that prompted me to file this bug.