Created attachment 1063935 [details]
File: backtrace

Created attachment 1063936 [details]
File: cgroup

Created attachment 1063937 [details]
File: core_backtrace

Created attachment 1063938 [details]
File: dso_list

Created attachment 1063939 [details]
File: environ

Created attachment 1063940 [details]
File: limits

Created attachment 1063941 [details]
File: maps

Created attachment 1063942 [details]
File: mountinfo

Created attachment 1063943 [details]
File: namespaces

Created attachment 1063944 [details]
File: open_fds

Created attachment 1063945 [details]
File: proc_pid_status

Created attachment 1063946 [details]
File: var_log_messages

Still occurs with gnome-shell-3.18.1-1.fc23.x86_64

How often does this occur for you?
Is there anything specific that triggers it?
Are there any Javascript exceptions in your journalctl logs before a crash?

 They would start with  gnome-session[1393]: (gnome-shell:1400): Gjs-WARNING **: JS ERROR: 

and then have several lines of backtrace following. (You can search for JS ERROR)

Do you have any GNOME Shell extensions installed?

Another user experienced a similar problem:

I was alt-tabbing while a VM was starting up in the background, I think.

reporter:       libreport-2.6.3
backtrace_rating: 3
cmdline:        /usr/bin/gnome-shell
crash_function: object_instance_trace
executable:     /usr/bin/gnome-shell
global_pid:     3296
kernel:         4.2.3-300.fc23.x86_64
package:        gnome-shell-3.18.1-1.fc23
reason:         gnome-shell killed by SIGSEGV
runlevel:       N 5
type:           CCpp
uid:            1001

There are no JS ERRORs around the time of the crash, here. 38 seconds earlier there's an goa-daemon warning, "Oct 27 11:27:30 adam.happyassassin.net org.gnome.OnlineAccounts[2985]: (goa-daemon:3347): GoaBackend-WARNING **: secret_password_lookup_sync() returned NULL".

(In reply to Owen Taylor from comment #14)
> How often does this occur for you?
it is happens sometimes without clear reason.

> Is there anything specific that triggers it?
May be moving window? I am not sure.

> Are there any Javascript exceptions in your journalctl logs before a crash?
> 
>  They would start with  gnome-session[1393]: (gnome-shell:1400): Gjs-WARNING
> **: JS ERROR: 
> 
> and then have several lines of backtrace following. (You can search for JS
> ERROR)

I see only this, but it happened 6 hours earlier

окт 27 11:53:50 localhost.localdomain dbus[845]: [system] Activating via systemd: service name='net.reactivated.Fprint' unit='fprintd.service'
окт 27 11:53:50 localhost.localdomain systemd[1]: Starting Fingerprint Authentication Daemon...
окт 27 11:53:50 localhost.localdomain dbus[845]: [system] Successfully activated service 'net.reactivated.Fprint'
окт 27 11:53:50 localhost.localdomain systemd[1]: Started Fingerprint Authentication Daemon.
окт 27 11:53:50 localhost.localdomain audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=fprintd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
окт 27 11:53:53 localhost.localdomain unix_chkpwd[1776]: password check failed for user (mikhail)
окт 27 11:53:53 localhost.localdomain gdm-password][1764]: pam_unix(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty= ruser= rhost=  user=mikhail
окт 27 11:53:53 localhost.localdomain audit[1764]: USER_AUTH pid=1764 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 msg='op=PAM:authentication grantors=? acct="mikhail" exe="/usr/libexec/gdm-session-worker" hostname=? addr=? terminal=? res=failed'
окт 27 11:53:55 localhost.localdomain audit[1764]: USER_LOGIN pid=1764 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 msg='uid=1000 exe="/usr/libexec/gdm-session-worker" hostname=? addr=? terminal=? res=failed'
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: (gnome-shell:2221): Gjs-WARNING **: JS ERROR: Gio.IOErrorEnum: The connection is closed
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: ShellUserVerifier<.cancel@resource:///org/gnome/shell/gdm/util.js:189
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: wrapper@resource:///org/gnome/gjs/modules/lang.js:169
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: AuthPrompt<.reset@resource:///org/gnome/shell/gdm/authPrompt.js:450
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: wrapper@resource:///org/gnome/gjs/modules/lang.js:169
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: AuthPrompt<.cancel@resource:///org/gnome/shell/gdm/authPrompt.js:521
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: wrapper@resource:///org/gnome/gjs/modules/lang.js:169
окт 27 11:53:56 localhost.localdomain gnome-session[2043]: AuthPrompt<._init/<@resource:///org/gnome/shell/gdm/authPrompt.js:82
окт 27 11:54:01 localhost.localdomain audit[1790]: USER_AUTH pid=1790 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 msg='op=PAM:authentication grantors=pam_unix,pam_gnome_keyring acct="mikhail" exe="/usr/libexec/gdm-session-worker" hostname=? addr=? terminal=? res=success'
окт 27 11:54:01 localhost.localdomain audit[1790]: USER_ACCT pid=1790 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 msg='op=PAM:accounting grantors=pam_unix,pam_localuser acct="mikhail" exe="/usr/libexec/gdm-session-worker" hostname=? addr=? terminal=? res=success'
окт 27 11:54:01 localhost.localdomain audit[1790]: CRED_REFR pid=1790 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:xdm_t:s0-s0:c0.c1023 msg='op=PAM:setcred grantors=pam_unix,pam_gnome_keyring acct="mikhail" exe="/usr/libexec/gdm-session-worker" hostname=? addr=? terminal=? res=success'
окт 27 11:54:20 localhost.localdomain audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=fprintd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
окт 27 11:54:46 localhost.localdomain org.gnome.OnlineAccounts[2039]: (goa-daemon:2303): GoaBackend-WARNING **: secret_password_lookup_sync() returned NULL
окт 27 11:54:46 localhost.localdomain org.gnome.OnlineAccounts[2039]: (goa-daemon:2303): GoaBackend-WARNING **: secret_password_lookup_sync() returned NULL
окт 27 11:54:48 localhost.localdomain org.gnome.OnlineAccounts[2039]: (goa-daemon:2303): GoaBackend-WARNING **: secret_password_lookup_sync() returned NULL
окт 27 11:54:49 localhost.localdomain org.gnome.OnlineAccounts[2039]: (goa-daemon:2303): GoaBackend-WARNING **: secret_password_lookup_sync() returned NULL
окт 27 11:55:26 localhost.localdomain org.gnome.OnlineAccounts[2039]: (goa-daemon:2303): GoaBackend-WARNING **: secret_password_lookup_sync() returned NULL


> Do you have any GNOME Shell extensions installed?
No.

Created attachment 1087058 [details]
full journal log here

Similar problem has been detected:

I'm using it as normal but suddenly it crashed.
No idea how to reproduce it.

reporter:       libreport-2.6.4
backtrace_rating: 4
cmdline:        /usr/bin/gnome-shell
crash_function: object_instance_trace
executable:     /usr/bin/gnome-shell
global_pid:     2501
kernel:         4.4.3-300.fc23.x86_64
package:        gnome-shell-3.18.3-1.fc23
reason:         gnome-shell killed by SIGSEGV
runlevel:       N 5
type:           CCpp
uid:            1000

*** Bug 1344725 has been marked as a duplicate of this bug. ***

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