Bug 1433420

Created attachment 1264078 [details]
File: backtrace

Created attachment 1264079 [details]
File: cgroup

Created attachment 1264080 [details]
File: core_backtrace

Created attachment 1264081 [details]
File: dso_list

Created attachment 1264082 [details]
File: environ

Created attachment 1264083 [details]
File: limits

Created attachment 1264084 [details]
File: maps

Created attachment 1264085 [details]
File: mountinfo

Created attachment 1264086 [details]
File: namespaces

Created attachment 1264087 [details]
File: open_fds

Created attachment 1264088 [details]
File: proc_pid_status

Created attachment 1264089 [details]
File: var_log_messages

What were you doing when this happened?

Can you duplicate the crash?

Yes using X2Go from a PC and the XFCE dropdown, it starts and then just quits.

xfwm4-4.12.4-1.fc25 has been submitted as an update to Fedora 25. https://bodhi.fedoraproject.org/updates/FEDORA-2017-ee90e7b000

xfwm4-4.12.4-1.fc26 has been submitted as an update to Fedora 26. https://bodhi.fedoraproject.org/updates/FEDORA-2017-15853d2654

xfwm4-4.12.4-1.fc25 has been pushed to the Fedora 25 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-ee90e7b000

xfwm4-4.12.4-1.fc26 has been pushed to the Fedora 26 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-15853d2654

rpm -q xfwm4
xfwm4-4.12.4-1.fc25.x86_64

Still crashes & coredump on Fedora 25.

dbus-daemon[8871]: [session uid=6105 pid=8869] Successfully activated service 'org.gtk.vfs.AfcVolumeMonitor'
kernel: xfce4-panel[9393]: segfault at 0 ip 00007f634e4826a7 sp 00007ffc5bef8858 error 4 in libX11-xcb.so.1.0.0[7f634e482000+1000]
systemd-coredump: Process 9393 (xfce4-panel) of user 6105 dumped core.#012#012Stack trace of thread 9393:#012#0  0x00007f634e4826a7 XGetXCBConnection (libX11-xcb.so.1)#012#1  0x00007f6352cfe1b2 sn_display_new (libstartup-notification-1.so.0)#012#2  0x00007f63565b267f wnck_screen_get (libwnck-1.so.22)#012#3  0x000055bb4e3a156a panel_window_screen_changed (xfce4-panel)#012#4  0x00007f63550767fb g_type_create_instance (libgobject-2.0.so.0)#012#5  0x00007f635505869b g_object_new_internal (libgobject-2.0.so.0)#012#6  0x00007f635505a5ae g_object_new_valist (libgobject-2.0.so.0)#012#7  0x00007f635505a851 g_object_new (libgobject-2.0.so.0)#012#8  0x000055bb4e3a3e38 panel_window_new (xfce4-panel)#012#9  0x000055bb4e3890b2 panel_application_new_window (xfce4-panel)#012#10 0x000055bb4e3893cc panel_application_load_real (xfce4-panel)#012#11 0x000055bb4e3897bc panel_application_wait_for_window_manager_destroyed (xfce4-panel)#012#12 0x00007f6354d77938 g_source_callback_unref (libglib-2.0.so.0)#012#13 0x00007f6354d79106 g_source_destroy_internal (libglib-2.0.so.0)#012#14 0x00007f6354d7af00 g_main_context_dispatch (libglib-2.0.so.0)#012#15 0x00007f6354d7b1d0 g_main_context_iterate.isra.24 (libglib-2.0.so.0)#012#16 0x00007f6354d7b4f2 g_main_loop_run (libglib-2.0.so.0)#012#17 0x00007f6356058267 gtk_main (libgtk-x11-2.0.so.0)#012#18 0x000055bb4e386f58 main (xfce4-panel)#012#19 0x00007f6354464401 __libc_start_main (libc.so.6)#012#20 0x000055bb4e3870d9 _start (xfce4-panel)
Mar 21 14:39:36  dbus-daemon[8871]: [session uid=6105 pid=8869] Activating service name='org.gtk.vfs.GoaVolumeMonitor' requested by ':1.12' (uid=6105 pid=8946 comm="/usr/libexec/tracker-extract ")
dbus-daemon[8871]: [session uid=6105 pid=8869] Successfully activated service 'org.gtk.vfs.GoaVolumeMonitor'
kernel: xfce4-panel[9455]: segfault at 0 ip 00007f7b7ad2a6a7 sp 00007ffc5c899df8 error 4 in libX11-xcb.so.1.0.0[7f7b7ad2a000+1000]
systemd: Started Process Core Dump (PID 9495/UID 0).
systemd-coredump: Removed old coredump core.marco.1000.c2b3c76b5fd04c8f981c941d5266a42d.16081.1489583034000000000000.lz4.
systemd-coredump: Process 9455 (xfce4-panel) of user 6105 dumped core.#012#012Stack trace of thread 9455:#012#0  0x00007f7b7ad2a6a7 XGetXCBConnection (libX11-xcb.so.1)#012#1  0x00007f7b7f5a61b2 sn_display_new (libstartup-notification-1.so.0)#012#2  0x00007f7b82e5a67f wnck_screen_get (libwnck-1.so.22)#012#3  0x0000560d747b156a panel_window_screen_changed (xfce4-panel)#012#4  0x00007f7b8191e7fb g_type_create_instance (libgobject-2.0.so.0)#012#5  0x00007f7b8190069b g_object_new_internal (libgobject-2.0.so.0)#012#6  0x00007f7b819025ae g_object_new_valist (libgobject-2.0.so.0)#012#7  0x00007f7b81902851 g_object_new (libgobject-2.0.so.0)#012#8  0x0000560d747b3e38 panel_window_new (xfce4-panel)#012#9  0x0000560d747990b2 panel_application_new_window (xfce4-panel)#012#10 0x0000560d747993cc panel_application_load_real (xfce4-panel)#012#11 0x0000560d747997bc panel_application_wait_for_window_manager_destroyed (xfce4-panel)#012#12 0x00007f7b8161f938 g_source_callback_unref (libglib-2.0.so.0)#012#13 0x00007f7b81621106 g_source_destroy_internal (libglib-2.0.so.0)#012#14 0x00007f7b81622f00 g_main_context_dispatch (libglib-2.0.so.0)#012#15 0x00007f7b816231d0 g_main_context_iterate.isra.24 (libglib-2.0.so.0)#012#16 0x00007f7b816234f2 g_main_loop_run (libglib-2.0.so.0)#012#17 0x00007f7b82900267 gtk_main (libgtk-x11-2.0.so.0)#012#18 0x0000560d74796f58 main (xfce4-panel)#012#19 0x00007f7b80d0c401 __libc_start_main (libc.so.6)#012#20 0x0000560d747970d9 _start (xfce4-panel)

Created attachment 1265190 [details]
core dump

Would you be able to file this upstream or would you prefer that I file it upstream?

Thanks!

If you could do it I would appreciate it, thanks. I take it this is separate from the issue that was just fixed?

If you could do it I would appreciate it, thanks. I take it this is separate from the issue that was just fixed?

I am not convinced this is a bug in xfwm4, or xfce4-panel for that matter (as both are mentioned in this bug, comment 0 and comment 19). but I suspect they are both victims of the display vanishing under their feet at startup.

Reason I believe so is because xfwm4 or xfce4-panel crashing won't cause the session to terminate (comment 14) and also, both backtraces point toward the same code in libstartup-notification but from two different components and code paths...

So if the session terminates, it's most likely xfce4-session that either dies or failed to start.

Best way to tell is to create a customer session in x2goclient and run just a bare xterm (Session type: "Custom desktop", Command "/usr/bin/xterm" - just make sure you have xterm installed first...) and then run "startxfce4" from this xterm and see what it says.

Yes "the display vanishing under their feet at startup" is exactly what happens. Here's what happends with startxfce, and I added --disable-wm-check but same results with and without that option.


startxfce4 --disable-wm-check
/bin/startxfce4: X server already running on display :58.0
xfce4-session-Message: SSH authentication agent is already running
gpg-agent[6002]: WARNING: "--write-env-file" is an obsolete option - it has no effect
gpg-agent: a gpg-agent is already running - not starting a new one

(xfce4-session:5998): xfce4-session-WARNING **: gpg-agent returned no PID in the variables

(xfce4-session:5998): xfce4-session-WARNING **: xfsm_manager_load_session: Something wrong with /.cache/sessions/xfce4-session-ourdomain:58, Does it exist? Permissions issue?

(xfwm4:6005): xfwm4-WARNING **: The display does not support the XComposite extension.

(xfwm4:6005): xfwm4-WARNING **: The display does not support the XFixes extension.
(xfwm4:6005): xfwm4-WARNING **: Compositing manager disabled.

(xfwm4:6005): xfwm4-WARNING **: Error opening /dev/dri/card0: Permission denied
vmware-user: could not open /proc/fs/vmblock/dev
SELinux Troubleshooter: Applet requires SELinux be enabled to run.
blueman-applet version 2.0.4 starting
Stale PID, overwriting
/usr/lib/python3.5/site-packages/blueman/plugins/applet/AppIndicator.py:8: PyGIWarning: AppIndicator3 was imported without specifying a version first. Use gi.require_version('AppIndicator3', '0.1') before import to ensure that the right version gets loaded.
  from gi.repository import AppIndiccator3 as girAppIndicator

and then... "startxfce4" ends, just like that?

What if you run "xfwm4 & xfce4-panel" instead, do they start?

"and then... "startxfce4" ends, just like that?"

Just these logs over & over:
xfce4-panel: No window manager registered on screen 0. To start the panel without this check, run with --disable-wm-check.

xfwm4 
(xfwm4:25954): xfwm4-WARNING **: The display does not support the XComposite extension.
(xfwm4:25954): xfwm4-WARNING **: The display does not support the XFixes extension.
(xfwm4:25954): xfwm4-WARNING **: Compositing manager disabled.
(xfwm4:25954): xfwm4-WARNING **: Error opening /dev/dri/card0: Permission denied
Segmentation fault (core dumped)

xfce4-panel
xfce4-panel: Failed to connect to session manager: Failed to connect to the session manager: SESSION_MANAGER environment variable not defined
xfce4-panel: No window manager registered on screen 0. To start the panel without this check, run with --disable-wm-check.
Segmentation fault (core dumped)

Would you like the core dumps?

If, from the very same xterm session you run some other gtk2 based app, say "gtk-demo", does it work?

After installing all the necessary packages for gtk-demo it starts and I see the "Application main window Demonstrates a typical application window with menubar, toolbar, statusbar."

Any update on a fix or what the root of the problem is?

Sorry, can't reproduce the issue, xfce works fine in x2go here between two different fedora 25 machines.

I would be interested in the xfwm4 core file...

Created attachment 1269745 [details]
xfwm4 core file

xfwm4 core file attached I also have cores for marco, xfce4 and using openbox.

(In reply to RobbieTheK from comment #32)
> xfwm4 core file attached I also have cores for marco, xfce4 and using
> openbox.

You mean you have all these (unrelated) apps segfaulting the same? That doesn't seem right...

The backtrace seems odd, dpy->xcb is NULL but this is not something xfwm4 does by itself.

Why is that set in your env?

    LD_LIBRARY_PATH=/usr/lib64/nx/X11/Xinerama:/usr/lib64/nx/X11

Are you using x2go from Fedora 25 packages? Is there anything in those paths?

Does "unset LD_LIBRARY_PATH; xfwm4 --compositor=off" make any difference?

Ah this is highly suspect to me:

From                To                  Syms Read   Shared Object Library
                                        No          /usr/lib64/nx/X11/libX11.so.6

So you're *not* using the libX11 from the OS/Fedora 25, and not too surprisingly, the crash occurs in the display structures...

I am quite convinced this is a issue in your environment, not using provided libraries.

"Why is that set in your env?

    LD_LIBRARY_PATH=/usr/lib64/nx/X11/Xinerama:/usr/lib64/nx/X11"

Not sure?

"Does "unset LD_LIBRARY_PATH; xfwm4 --compositor=off" make any difference?"
 unset LD_LIBRARY_PATH; xfwm4 --compositor=off

(xfwm4:22503): Gtk-WARNING **: cannot open display:

"Are you using x2go from Fedora 25 packages?"

 dnf info libX11*
Last metadata expiration check: 0:53:26 ago on Fri Apr  7 11:25:27 2017.
Installed Packages
Name        : libX11
Arch        : i686
Epoch       : 0
Version     : 1.6.4
Release     : 4.fc25
Size        : 1.3 M
Repo        : @System
From repo   : updates
Summary     : Core X11 protocol client library
URL         : http://www.x.org
License     : MIT
Description : Core X11 protocol client library.

Name        : libX11
Arch        : x86_64
Epoch       : 0
Version     : 1.6.4
Release     : 4.fc25
Size        : 1.3 M
Repo        : @System
From repo   : updates
Summary     : Core X11 protocol client library
URL         : http://www.x.org
License     : MIT
Description : Core X11 protocol client library.

Name        : libX11-common
Arch        : noarch
Epoch       : 0
Version     : 1.6.4
Release     : 4.fc25
Size        : 1.3 M
Repo        : @System
From repo   : updates
Summary     : Common data for libX11
URL         : http://www.x.org
License     : MIT
Description : libX11 common data

Name        : libX11-devel
Arch        : x86_64
Epoch       : 0
Version     : 1.6.4
Release     : 4.fc25
Size        : 1.0 M
Repo        : @System
From repo   : updates
Summary     : Development files for libX11
URL         : http://www.x.org
License     : MIT
Description : X.Org X11 libX11 development package

Available Packages
Name        : libX11-devel
Arch        : i686
Epoch       : 0
Version     : 1.6.4
Release     : 4.fc25
Size        : 982 k
Repo        : updates
Summary     : Development files for libX11
URL         : http://www.x.org
License     : MIT
Description : X.Org X11 libX11 development package

dnf info x2go*
Last metadata expiration check: 0:57:23 ago on Fri Apr  7 11:25:27 2017.
Installed Packages
Name        : x2goagent
Arch        : x86_64
Epoch       : 0
Version     : 3.5.0.32
Release     : 4.fc24
Size        : 37 k
Repo        : @System
From repo   : fedora
Summary     : X2Go Agent
URL         : http://x2go.org/
License     : GPLv2+
Description : X2Go agent functionality has been completely incorporated into
            : nxagent's code base. If the nxagent binary is executed under the name
            : of "x2goagent", the X2Go functionalities get activated.
            :
            : The x2goagent package is a wrapper that activates X2Go branding in
            : nxagent. Please refer to the nxagent package's description for more
            : information on NX.

Name        : x2goserver
Arch        : x86_64
Epoch       : 0
Version     : 4.0.1.20
Release     : 1.fc25
Size        : 309 k
Repo        : @System
From repo   : updates
Summary     : X2Go Server
URL         : http://www.x2go.org
License     : GPLv2+
Description : X2Go is a server based computing environment with
            :     - session resuming
            :     - low bandwidth support
            :     - session brokerage support
            :     - client side mass storage mounting support
            :     - audio support
            :     - authentication by smartcard and USB stick
            :
            : This package contains the main daemon and tools for X2Go server-side session
            : administrations.

Name        : x2goserver-xsession
Arch        : x86_64
Epoch       : 0
Version     : 4.0.1.20
Release     : 1.fc25
Size        : 8.7 k
Repo        : @System
From repo   : updates
Summary     : X2Go Server Xsession runner
URL         : http://www.x2go.org
License     : GPLv2+
Description : X2Go is a server based computing environment with
            :    - session resuming
            :    - low bandwidth support
            :    - session brokerage support
            :    - client side mass storage mounting support
            :    - audio support
            :    - authentication by smartcard and USB stick
            :
            : This X2Go server add-on enables Xsession script handling
            : when starting desktop sessions with X2Go.
            :
            : Amongst others the parsing of Xsession scripts will
            : enable desktop-profiles, ssh-agent startups, gpgagent
            : startups and many more Xsession related features on
            : X2Go session login automagically.

That doesn't prove that the file comes from the packages :)

What gives:

  $ ls -l /usr/lib64/nx/X11/libX11.so.6
  $ rpm -qf /usr/lib64/nx/X11/libX11.so.6

On your system? (since that's the actual libX11 being loaded there)

As a comparison, I have here:

  $ ls /usr/lib64/nx/X11/libX11.so.6
  ls: cannot access '/usr/lib64/nx/X11/libX11.so.6': No such file or directory

  => So there is no such file on my system

But some of the directories do exist:

  $ ls /usr/lib64/nx/X11/
  Xinerama
  $ ls -l /usr/lib64/nx/X11/Xinerama/
  total 0
  lrwxrwxrwx. 1 root root 29 Feb 11 10:35 libNX_X11.so.6 -> ../../../../lib64/libX11.so.6
  lrwxrwxrwx. 1 root root 30 Feb 11 10:35 libNX_Xext.so.6 -> ../../../../lib64/libXext.so.6
  lrwxrwxrwx. 1 root root 25 Feb 11 10:35 libXinerama.so.1 -> ../../libNX_Xinerama.so.1

 => So those are supposed to be symlinks to the standard libs provided by Fedora. Is that the case on your system?

ls -l /usr/lib64/nx/X11/libX11.so.6
lrwxrwxrwx 1 root root 20 Mar  8 21:35 /usr/lib64/nx/X11/libX11.so.6 -> ../../libNX_X11.so.6

rpm -qf /usr/lib64/nx/X11/libX11.so.6
nxagent-3.5.99.4-0.0build1.fc25.x86_64

ls /usr/lib64/nx/X11/
libNX_X11.so.6  libX11.so.6  libX11.so.6.2


ls -l /usr/lib64/nx/X11/Xinerama
ls: cannot access '/usr/lib64/nx/X11/Xinerama': No such file or directory


OK looks like at some point I enabled the copr repo from https://copr.fedorainfracloud.org/coprs/mikedep333/nx-libs-3.6/build/524054/

Should I remove those?

That's completely up to you to decide, I don't know these builds... If I was me, I would stick to the builds provided by Fedora. Those work here.

All I know is that the core file shows the process is using a non-standard libX11 and the odd crash occurs in the display (created by libX11) and is affecting several different unrelated projects  - i.e. I am quite convinced this is not a bug in xfwm4.

Created attachment 1269835 [details]
coredump

OK here's a coredump from a server that is not using the updated NX libs.

And:
more core_backtrace
{   "signal": 11
,   "executable": "/usr/bin/xfdesktop"
,   "only_crash_thread": true
,   "stacktrace":
      [ {   "crash_thread": true
        ,   "frames":
              [ {   "address": 140025185842855
                ,   "build_id": "2cd49b4e4b0afdee8f342a7bd699e4656d95e0fc"
                ,   "build_id_offset": 1703
                ,   "function_name": "XGetXCBConnection"
                ,   "file_name": "/usr/lib64/libX11-xcb.so.1.0.0"
                }
              , {   "address": 140025263362482
                ,   "build_id": "774b2e67d0deb0d3f0a214b91e0aa68afd605fb6"
                ,   "build_id_offset": 12722
                ,   "function_name": "sn_display_new"
                ,   "file_name": "/usr/lib64/libstartup-notification-1.so.0.0.0"
                }
              , {   "address": 140025343317631
                ,   "build_id": "3de7365af2d70c17a8aec76de4283e7099f8d1da"
                ,   "build_id_offset": 83583
                ,   "function_name": "wnck_screen_get"
                ,   "file_name": "/usr/lib64/libwnck-1.so.22.4.0"
                }
              , {   "address": 94852561572451
                ,   "build_id": "1eb986ee199e86508279d2953d8f7b2c34220065"
                ,   "build_id_offset": 115299
                ,   "function_name": "xfce_desktop_realize"
                ,   "file_name": "/usr/bin/xfdesktop"
                }
              , {   "address": 140025286550501
                ,   "build_id": "8f0af3ac13665e292515639f3557b9f9c9b59b7c"
                ,   "build_id_offset": 62437
                ,   "function_name": "g_closure_invoke"
                ,   "file_name": "/usr/lib64/libgobject-2.0.so.0.5000.3"
                }
              , {   "address": 140025286622724
                ,   "build_id": "8f0af3ac13665e292515639f3557b9f9c9b59b7c"
                ,   "build_id_offset": 134660
                ,   "function_name": "signal_emit_unlocked_R"
                ,   "file_name": "/usr/lib64/libgobject-2.0.so.0.5000.3"
                }
              , {   "address": 140025286660191
                ,   "build_id": "8f0af3ac13665e292515639f3557b9f9c9b59b7c"
                ,   "build_id_offset": 172127
                ,   "function_name": "g_signal_emit_valist"
                ,   "file_name": "/usr/lib64/libgobject-2.0.so.0.5000.3"
                }
              , {   "address": 140025286661183
                ,   "build_id": "8f0af3ac13665e292515639f3557b9f9c9b59b7c"
                ,   "build_id_offset": 173119
                ,   "function_name": "g_signal_emit"
                ,   "file_name": "/usr/lib64/libgobject-2.0.so.0.5000.3"
                }
              , {   "address": 140025322594292
                ,   "build_id": "83b153c37b177bbcfcab011672f28fba50de4e44"
                ,   "build_id_offset": 2596852
                ,   "function_name": "gtk_widget_realize"
                ,   "file_name": "/usr/lib64/libgtk-x11-2.0.so.0.2400.31"
                }
              , {   "address": 94852561583245
                ,   "build_id": "1eb986ee199e86508279d2953d8f7b2c34220065"
                ,   "build_id_offset": 126093
                ,   "function_name": "xfdesktop_application_start"
                ,   "file_name": "/usr/bin/xfdesktop"
                }
              , {   "address": 94852561584314
                ,   "build_id": "1eb986ee199e86508279d2953d8f7b2c34220065"
                ,   "build_id_offset": 127162
                ,   "function_name": "cb_wait_for_window_manager_destroyed"
                ,   "file_name": "/usr/bin/xfdesktop"
                }
              , {   "address": 140025283553592
                ,   "build_id": "3b5186f89b9971902d8124e8eee90486b1e569de"
                ,   "build_id_offset": 289080
                ,   "function_name": "g_source_callback_unref"
                ,   "file_name": "/usr/lib64/libglib-2.0.so.0.5000.3"
                }
              , {   "address": 140025283559686
                ,   "build_id": "3b5186f89b9971902d8124e8eee90486b1e569de"
                ,   "build_id_offset": 295174
                ,   "function_name": "g_source_destroy_internal"
                ,   "file_name": "/usr/lib64/libglib-2.0.so.0.5000.3"
                }
              , {   "address": 140025283567360
                ,   "build_id": "3b5186f89b9971902d8124e8eee90486b1e569de"
                ,   "build_id_offset": 302848
                ,   "function_name": "g_main_context_dispatch"
                ,   "file_name": "/usr/lib64/libglib-2.0.so.0.5000.3"
                }
              , {   "address": 140025283568080
                ,   "build_id": "3b5186f89b9971902d8124e8eee90486b1e569de"
                ,   "build_id_offset": 303568
                ,   "function_name": "g_main_context_iterate.isra.24"
                ,   "file_name": "/usr/lib64/libglib-2.0.so.0.5000.3"
                }
              , {   "address": 140025283568252
                ,   "build_id": "3b5186f89b9971902d8124e8eee90486b1e569de"
                ,   "build_id_offset": 303740
                ,   "function_name": "g_main_context_iteration"
                ,   "file_name": "/usr/lib64/libglib-2.0.so.0.5000.3"
                }
              , {   "address": 140025294273437
                ,   "build_id": "48ad6b28698fcd7a879b133df3563a164f8d51d7"
                ,   "build_id_offset": 646045
                ,   "function_name": "g_application_run"
                ,   "file_name": "/usr/lib64/libgio-2.0.so.0.5000.3"
                }
              , {   "address": 94852561539517
                ,   "build_id": "1eb986ee199e86508279d2953d8f7b2c34220065"
                ,   "build_id_offset": 82365
                ,   "function_name": "main"
                ,   "file_name": "/usr/bin/xfdesktop"
                } ]
        } ]
}

I am the maintainer of that copr repo.

This bug only occurs with nx-libs 3.6 (in beta), not nx-libs 3.5, which is in all Fedora and EPEL releases.

I have submitted it upstream.
https://github.com/ArcticaProject/nx-libs/issues/420

xfwm4-4.12.4-1.fc26 has been pushed to the Fedora 26 stable repository. If problems still persist, please make note of it in this bug report.

xfwm4-4.12.4-1.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.

Similar problem has been detected:

using X2Go with XFCE

reporter:       libreport-2.8.0
backtrace_rating: 4
cmdline:        xfwm4
crash_function: XGetXCBConnection
executable:     /usr/bin/xfwm4
global_pid:     24707
kernel:         4.10.8-200.fc25.x86_64
package:        xfwm4-4.12.4-1.fc25
pkg_fingerprint: 4089 D8F2 FDB1 9C98
pkg_vendor:     Fedora Project
reason:         xfwm4 killed by SIGSEGV
runlevel:       N 5
type:           CCpp
uid:            6105

(In reply to RobbieTheK from comment #46)
> Similar problem has been detected:
> 
> using X2Go with XFCE

This a problem with x2go, not xfwm4.

(In reply to Olivier Fourdan from comment #47)
> (In reply to RobbieTheK from comment #46)
> > Similar problem has been detected:
> > 
> > using X2Go with XFCE
> 
> This a problem with x2go, not xfwm4.

Can you change this to an Fedora-X2Go bug and reassign?

Seeing this error:
TRACE[xfsm-manager.c:1295] xfsm_manager_save_yourself_done(): enteringTRACE[ice-layer.c:99] ice_error_handler(): ICE connection fd = 20, ICE I/O error on connection

*** Bug 1433419 has been marked as a duplicate of this bug. ***

*** Bug 1433449 has been marked as a duplicate of this bug. ***

*** Bug 1435677 has been marked as a duplicate of this bug. ***

As indicated in https://github.com/ArcticaProject/nx-libs/issues/420 this generally is a mismatch between x2goserver and nx-libs versions.  Robbie - are you sure you can reproduce with a stock Fedora install?

(In reply to Orion Poplawski from comment #53)
> As indicated in https://github.com/ArcticaProject/nx-libs/issues/420 this
> generally is a mismatch between x2goserver and nx-libs versions.  Robbie -
> are you sure you can reproduce with a stock Fedora install?

This only happens to one NIS user. I upgraded X2Goserver to 4.1 and same--keeps getting a protocol mismatch error. I deleted both ~/.config/xfce4  & ~/.ICEauthority and same. MATE crashes as well.

I think you're going to need to figure out what it different in the user's environment.

(In reply to Orion Poplawski from comment #55)
> I think you're going to need to figure out what it different in the user's
> environment.

What preferences/files should I be looking in?

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