gnome-shell crashed with SIGSEGV in meta_monitor_manager_get_monitor_for_connector() from <JavaScript>

[Kostadin Stoilov]

https://errors.ubuntu.com/problem/6651d911f833729ccc39cf01ed5e393b95cb0c3f

gnome shell crashes when I go to Settings -> Devices -> Displays

ProblemType: Crash
DistroRelease: Ubuntu 18.04
Package: gnome-shell 3.28.4-0ubuntu18.04.1
ProcVersionSignature: Ubuntu 4.18.0-22.23~18.04.1-generic 4.18.20
Uname: Linux 4.18.0-21-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.6
Architecture: amd64
CrashCounter: 1
CurrentDesktop: ubuntu:GNOME
Date: Wed Jun 19 11:01:41 2019
DisplayManager: gdm3
ExecutablePath: /usr/bin/gnome-shell
InstallationDate: Installed on 2016-04-29 (1146 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
ProcCmdline: /usr/bin/gnome-shell
SegvAnalysis:
 Segfault happened at: 0x7f49b8116bf0 <meta_monitor_manager_get_monitor_for_connector+80>: mov 0x18(%rax),%eax
 PC (0x7f49b8116bf0) ok
 source "0x18(%rax)" (0x00000018) not located in a known VMA region (needed readable region)!
 destination "%eax" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: gnome-shell
StacktraceTop:
 meta_monitor_manager_get_monitor_for_connector () at /usr/lib/x86_64-linux-gnu/libmutter-2.so.0
 ffi_call_unix64 () at /usr/lib/x86_64-linux-gnu/libffi.so.6
 ffi_call () at /usr/lib/x86_64-linux-gnu/libffi.so.6
 () at /usr/lib/libgjs.so.0
 () at /usr/lib/libgjs.so.0
Title: gnome-shell crashed with SIGSEGV in meta_monitor_manager_get_monitor_for_connector()
UpgradeStatus: Upgraded to bionic on 2018-08-04 (319 days ago)
UserGroups: adm cdrom dip docker kvm libvirt libvirtd lpadmin plugdev sambashare sudo

[Apport retracing service (apport)]

StacktraceTop:
 meta_monitor_manager_get_monitor_for_connector (manager=<optimized out>, connector=0x564d1deed7e0 "eDP-1") at backends/meta-monitor-manager.c:2936
 ffi_call_unix64 () at ../src/x86/unix64.S:76
 ffi_call (cif=cif@entry=0x7f491687fb78, fn=<optimized out>, rvalue=<optimized out>, rvalue@entry=0x7ffded562668, avalue=avalue@entry=0x7ffded562550) at ../src/x86/ffi64.c:525
 gjs_invoke_c_function (context=context@entry=0x564d1a974600, function=function@entry=0x7f491687fb60, obj=..., obj@entry=..., args=..., js_rval=..., r_value=r_value@entry=0x0) at gi/function.cpp:1088
 function_call (context=context@entry=0x564d1a974600, js_argc=1, vp=0x564d1aaaf658) at gi/function.cpp:1406

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel van Vugt (vanvugt)]

Tracking in: https://errors.ubuntu.com/problem/6651d911f833729ccc39cf01ed5e393b95cb0c3f

[Daniel van Vugt (vanvugt)]

It appears there's only one caller of this function in gnome-shell:

js/ui/osdMonitorLabeler.js: let monitor = this._monitorManager.get_monitor_for_connector(connector);

[finn (finn-uni-bremen)]

For me the root cause seems to be a problem with the i915 driver and multihead. With Kernel 4.19.69 it works. See https://bbs.archlinux.org/viewtopic.php?id=247904

[Daniel van Vugt (vanvugt)]

Zero crashes after 19.10 so consider it fixed.