Xwayland crashed with SIGABRT in OsAbort() from AbortServer() from FatalError() from xwl_read_events() from ospoll_wait()

[Jean-Baptiste Lallement]

https://errors.ubuntu.com/problem/c27f5c4fef272640ec1027318712f0434c7c8857

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Xwayland crashes when gnome-shell goes away. This isn't really a bug, but could always be handled a little better...

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ProblemType: Crash
DistroRelease: Ubuntu 18.04
Package: xwayland 2:1.19.5-0ubuntu2
ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4
Uname: Linux 4.13.0-16-generic x86_64
ApportVersion: 2.20.7-0ubuntu4
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: GNOME-Greeter:GNOME
Date: Mon Nov 13 13:55:16 2017
DistUpgraded: Fresh install
DistroCodename: bionic
DistroVariant: ubuntu
DkmsStatus:
 bbswitch, 0.8, 4.13.0-15-generic, x86_64: installed
 bbswitch, 0.8, 4.13.0-16-generic, x86_64: installed
ExecutablePath: /usr/bin/Xwayland
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: ASUSTeK Computer Inc. 3rd Gen Core processor Graphics Controller [1043:1507]
InstallationDate: Installed on 2013-09-03 (1531 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Alpha amd64 (20130902)
MachineType: ASUSTeK COMPUTER INC. UX32VD
ProcCmdline: /usr/bin/Xwayland :1024 -rootless -terminate -core -listen 4 -listen 5 -displayfd 6
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=fr_FR.UTF-8
 SHELL=/bin/false
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.13.0-16-generic root=UUID=1004226d-a9db-46c7-bd28-eca0806c12f2 ro pcie_aspm=force drm.vblankoffdelay=1 i915.semaphores=1 init=/lib/systemd/systemd-bootchart
Signal: 6
SourcePackage: xorg-server
StacktraceTop:
 OsAbort ()
 ?? ()
 FatalError ()
 ?? ()
 ?? ()
Title: Xwayland crashed with SIGABRT in OsAbort()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

dmi.bios.date: 01/29/2013
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: UX32VD.214
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: UX32VD
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrUX32VD.214:bd01/29/2013:svnASUSTeKCOMPUTERINC.:pnUX32VD:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnUX32VD:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.family: UX
dmi.product.name: UX32VD
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.85-1
version.libgl1-mesa-dri: libgl1-mesa-dri 17.2.2-0ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx 17.2.2-0ubuntu1
version.xserver-xorg-core: xserver-xorg-core 2:1.19.5-0ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.5-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.10.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20170309-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2

[Michael (michael-redhat-bugs)]

Version-Release number of selected component:
xorg-x11-server-Xwayland-1.19.3-4.fc26

Additional info:
reporter: libreport-2.9.1
backtrace_rating: 4
cmdline: /home/mcatanzaro/Projects/GNOME/install/bin/Xwayland :1 -rootless -terminate -core -listen 4 -listen 5 -displayfd 6
crash_function: xwl_read_events
executable: /usr/bin/Xwayland
journald_cursor: s=ca44c691f28b4a3fa6affd95ab5151f5;i=1b36b7;b=1bb81d6006b3438f9124fe2aa5b58740;m=a0fe9fcbc;t=55ce29a097191;x=9b45217435b11c67
kernel: 4.13.9-200.fc26.x86_64
rootdir: /
runlevel: N 5
type: CCpp
uid: 1000

[Michael (michael-redhat-bugs)]

Created attachment 1350099
File: backtrace

[Michael (michael-redhat-bugs)]

Created attachment 1350100
File: cgroup

[Michael (michael-redhat-bugs)]

Created attachment 1350101
File: core_backtrace

[Michael (michael-redhat-bugs)]

Created attachment 1350102
File: cpuinfo

[Michael (michael-redhat-bugs)]

Created attachment 1350103
File: dso_list

[Michael (michael-redhat-bugs)]

Created attachment 1350104
File: environ

[Michael (michael-redhat-bugs)]

Created attachment 1350105
File: limits

[Michael (michael-redhat-bugs)]

Created attachment 1350106
File: maps

[Michael (michael-redhat-bugs)]

Created attachment 1350107
File: open_fds

[Michael (michael-redhat-bugs)]

Created attachment 1350108
File: proc_pid_status

[Michael (michael-redhat-bugs)]

Created attachment 1350109
File: var_log_messages

[Olivier (olivier-redhat-bugs)]

Same as bug 1510078, this is a abort() because Xwayland (Wayland client) cannot read events from the Wayland compositor (gnome-shell.mutter, presumably) which is most likely a crash in gnome-shell/mutter in the first place.

xwl_read_events() aborts in two cases, either it fails to read the events (wl_display_read_events) or it fails to dispatch the events (wl_display_dispatch_pending), in both cases it's a communication issue with the Wayland compositor.

Can you quickly check in the logs at the time of the crash if gnome-shell/mutter had crashed or failed to start (I've seen this happening as well at startup, gnome-shell starts, spawns Xwayland, then fails, and Xwayland aborts in xwl_read_events())

[Apport retracing service (apport)]

StacktraceTop:
 OsAbort () at ../../../../os/utils.c:1361
 AbortServer () at ../../../../os/log.c:877
 FatalError (f=f@entry=0x559808cfd640 "failed to read Wayland events: %s\n") at ../../../../os/log.c:1015
 xwl_read_events (xwl_screen=0x55980a5c4a40) at ../../../../../hw/xwayland/xwayland.c:594
 ospoll_wait (ospoll=0x55980a5b9a20, timeout=<optimized out>) at ../../../../os/ospoll.c:412

[Launchpad Janitor (janitor)]

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

[Justin (justin-redhat-bugs)]

I am also experiencing this on Fedora 27, 4.14.0-1, Nouveau, t I think you're right Olivier, this is likely from a crash in mutter:

I see in the logs:
gnome-shell: segfault at ... in libmutter-1.so.0.0.0...
gnome-logs: Error reading events from display: Connection reset by peer
kernel: (EE)
Xwayland: ANOM_ABEND ...
gnome-session-b: gnome-session-binary: WARNING: Application 'org.gnome.Shell.desktop' killed by signal 11

(stack trace...)
systemd:coredum: Process 2515 (gnome-shell) of user 1000 dumped core.

The stack trace has:
#0 and #1 in libc.so.6
#2 OsAbort (Xwayland)
#3 AbortServer (Xwayland)
#4 FatalError (Xwayland)
#5 xwl_read_events (Xwayland)
#6 ospoll_wait (Xwayland)

I haven't been able to determine if some user action causes this. It seems to happen when I have the screen off (perhaps a notification triggers this crash? or turning the screen on, which activates the Displayport link, triggers the crash?)

I have mutter and gnome-shell at 3.26.2-1, and gnome-session(-xsession, -wayland-session) at 3.26.1-1.

Please let me know what more would be useful.

[Justin Chiu (c-justin88)]

I am on F26 and also seeing this bug, as reported here: https://bugzilla.redhat.com/show_bug.cgi?id=1511681

[Brian Neltner (neltnerb)]

I previously had bug https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1724557 which causes the desktop to hard crash when the monitor is turned on, related to gnome-shell and mutter.

That bug hasn't reported anything to /var/crash lately, but the behavior has stayed the same for me. If I turn my monitor off while playing music, when I turn it back on the desktop session has crashed and I have to start a new session. The music makes pretty clear that it is specifically related to the monitor turning on.

Now the crash report coinciding with the crash of the desktop session with the correct timestamp is a duplicate of this one. I am not sure if the two bugs are connected, but I get it when I turn my monitor on.

[Lars Falk-Petersen (julenissen)]

I think this hits me when moving Firefox between monitors.

[rugk (rugk-redhat-bugs)]

Maybe that is related to my issue Bug 1513807 ?

[Raymond (raymond-redhat-bugs)]

I was also experiencing this same problem after fresh install of Fedora 27. The problem is easily and always reproducible. The steps are :

1. login properly
2. power off monitor (or wait until screen saver cause the monitor to auto-sleep)
3. power back on the monitor (or wake-up from monitor sleep mode)

It reports "gnome-shell" was crashed and I have to re-login again.

I used just an ordinary HDMI full-HD monitor. This always happens, even just after fresh reboot. Should be something when the HDMI connection back on caused something to crash.

[Olivier (olivier-redhat-bugs)]

This is simply Xwayland telling your Wayland compositor (namely gnome-shell/mutter) has died.

Basically, gnome-shell (now) runs Xwayland with “-core” which means that *any* FatalError() in Xwayland will dump a core file.

xwl_read_events() triggers a FatalError() because the Wayland socket is unusable, and it's unusable because the Wayland compositor (the other side of the socket) has died, i.e. crashed most likely.

The Wayland compositor is gnome-shell/mutter, so if you could please look into journalctl and coredumpctl to find a backtrace and/or generate one with coredumpctl and gdb.

From comment 15, this is most likely a dupe of bug 1500325.

[Daniel van Vugt (vanvugt)]

This bug is also being tracked in:
https://errors.ubuntu.com/problem/c27f5c4fef272640ec1027318712f0434c7c8857

[Daniel van Vugt (vanvugt)]

NOTE: According to bug 1742544 and bug 1742545, this crash may happen if you manually turn your monitor off.

[Brian Neltner (neltnerb)]

I don't know how to tell if it's definitely the same, but for me the crash occurs not when the monitor is turned off but rather when it is turned back on. The actual time stamp of the crash isn't until after turning it on.

[jrstravino (jrstravino)]

Whenever I turn off my screen and then turn it on the problem occurs. the computer (a desktop PC) logs me out of my session.
When I wake the screen, I get the GDM login screen and a new session opens.
The previous session is lost.

[Timo Aaltonen (tjaalton)]

the fedora bug says it's a bug in mutter, fixed by

https://git.gnome.org/browse/mutter/commit/?h=gnome-3-26&id=cde5454622d99320a66f2fd352df132a4bfdab4b

[Launchpad Janitor (janitor)]

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

[Daniel van Vugt (vanvugt)]

OK, if that's the fix then we'll get it in mutter 3.26.3. Now looking forward to that one even more.

[Wellington Uemura (wellingtonuemura)]

This bug still not fixed, adding a core dump and this might have relations to bug #1743732 because if you turn the monitor off or lock the screen, everything in that session are lost. Daniel van Vugt asked to move that bug to private.

Core was generated by `/usr/bin/Xwayland :0 -rootless -terminate -core -listen 4 -listen 5 -displayfd'.

[Marcelo Bello (marcelo-bello)]

I experienced this crash today. Looking at dmesg the only suspicious line I found was this one:

[397641.528873] traps: gnome-shell[11133] general protection ip:7f5498d62de2 sp:7ffdd8da76f0 error:0 in libgobject-2.0.so.0.5400.1[7f5498d2d000+52000]

[Kir Kolyshkin (kolyshkin)]

This bug bite me on a daily basis, too (in Artful). I'm currently testing if the fix from Fedora (a cumulative patch of the first 30+ commits landed in mutter-3.26 branch after mutter-3.26.2 release) helps. Will report back soon.

[Seth Forshee (sforshee)]

My bug was duped to this one. After dist-upgrading 18.04 yesterday I consistently get a crash logging into any gnome sessions, only the unity session doesn't crash on me.

[Brian Neltner (neltnerb)]

Crash still occurs every time I turn my monitor back on, as has been the case since October.

[Federico Piantoni (fireb86)]

Crash occurs every time I turn the monitor off, in my case. Motherb.: Asrock J4205-itx (Intel HD graphics 505)

[Stuart (shutch)]

@Kir Kolyshkin - did trying the commits on the master branch of mutter after 3.26 fix this?

[Mathieu St-Gelais (mathieu-stgelais)]

I'm on Ubuntu 18.04, still beta, but fully updated, with dual screens on two AMD R9 390, and it keeps happening after each login / screen unlock.

[Andreas Enström (anen)]

Crashed at the same time as I got "gnome-shell crashed with SIGSEGV in cogl_object_unref()" after entering xorg session from the gnome-greeter lock-screen. I am not sure if it is related but I had problems with the wayland sessions crashing in the begining, until I changed to single monitor in the settings. For some reason the os detects my unplugged vga connector and wants to use it as an extended screen. I have no idea what the greeter sees or how it handles that, or if it's related at all.

[Daniel van Vugt (vanvugt)]

I think there are going to be multiple ways this Xwayland crash could be triggered. Also we don't seem to have fully deduplicated similar crashes yet:
https://bugs.launchpad.net/ubuntu/+source/xorg-server

So I think it's most helpful to keep this bug open and findable for now.

[Brian Neltner (neltnerb)]

I'm still seeing crashes under the exact same conditions as since October. When I do ubuntu-bug on the crash file it directs me here, so I think this bug may still be getting triggered for me at least.

[Daniel van Vugt (vanvugt)]

Bump. This bug is the top Xwayland crash by an order of magnitude:
https://errors.ubuntu.com/?package=xwayland&period=month

[Jeff Silverman (jeffsilverm)]

I think I'm experiencing the same problem. I installed Ubuntu 18.04 beta last Tuesday. When I power on my computer, the screen blinks 50-53 times over the span of 2-1/2 minutes (this is perfectly reproducible) and then for the rest of the session, everything works flawlessly. After LinuxFest Northwest, I was told to do an apt dist-upgrade and that did not clear the problem.

I have two video cards:
VGA compatible controller: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller (rev 09)
VGA compatible controller: NVIDIA Corporation GF108 [GeForce GT 430] (rev a1)

I'm not sure what other information would be helpful.

[Daniel van Vugt (vanvugt)]

Just tidying up this bug...

Although this is the top Xwayland crash, I'm now thinking we need to lower its priority. The reason is that this crash is only a side-effect of the gnome-shell process going away and not really a bug in Xwayland. One could argue that Xwayland still shouldn't crash in that case, and should survive (or exit) more cleanly. But still, not really a bug in Xwayland itself.

We need to focus on fixing the gnome-shell crashes more than this one, and then this one will happen much less.

[Brian Neltner (neltnerb)]

I'm not going to go so far as to say the bug itself is fixed, but upon upgrading to Bionic it is no longer using Wayland by default so...

no longer a bug that affects me at least. I'd suggest others try upgrading and switching to the new default window manager and backend.

[Daniel van Vugt (vanvugt)]

This bug is not fixed and frankly may never be fixed. It is also not a high priority. See comment #47 for why.

[Daniel van Vugt (vanvugt)]

Interesting that errors.ubuntu.com is showing zero reports of this crash in 19.04, and zero reports in the final release version of Xorg for 18.10 onward. But those same Xorg versions are crashing in 18.04. So I would have to conclude that this was fixed in mutter in Ubuntu 18.10 onward.