Bug 460336

it appears this segfault didn't create a core dump?

$ coredumpctl
No coredumps found.

Created attachment 152759 [details]
sddm wayland-session.log

This is the second crash in kwin_wayland

Before restarting sddm I saved the ssdm wayland-session.log and have attached it here for you.

You can see PhpStorm complaining about some stuff (\Traversable, \Doctrine* stuff) and what happens when it goes bang

We can't do anything about this bug report without a backtrace or reproducible steps to reproduce the crash.

(In reply to Vlad Zahorodnii from comment #3)
> We can't do anything about this bug report without a backtrace or
> reproducible steps to reproduce the crash.

I understand, I am trying to figure out how to do  it.

It's just happened a 3rd time, the kwin_wayland process is still there this time

Created attachment 152762 [details]
output of gdb

Output of using the command from https://community.kde.org/KWin/Debugging#Debug_KWin_with_GDB

sudo gdb -pid $(pidof kwin_wayland) -batch -ex "set logging file kwin_wayland.gdb" -ex "set logging on" -ex "continue" -ex "thread apply all backtrace" -ex "quit"

note: This was run a few minutes *after* the sudden black screen with movable mouse cursor.

Unsure if this is related - it appears in the systemd logs around the time of the sddm restart (which is around 20 minutes after the "crash"?)

Oct 13 16:24:06 jason-desktop systemd-coredump[94616]: Process 94612 (xdg-desktop-por) of user 117 dumped core.

Stack trace of thread 94612:
#0  0x00007f96af46f00b __GI_raise (libc.so.6 + 0x4300b)
#1  0x00007f96af44e859 __GI_abort (libc.so.6 + 0x22859)
#2  0x00007f96af892bd9 qt_message_fatal (libQt5Core.so.5 + 0x92bd9)
#3  0x00007f96b0739d9b init_platform (libQt5Gui.so.5 + 0x139d9b)
#4  0x00007f96b073a218 _ZN22QGuiApplicationPrivate21createEventDispatcherEv (libQt5Gui.so.5 + 0x13a218)
#5  0x00007f96afabbb06 _ZN23QCoreApplicationPrivate4initEv (libQt5Core.so.5 + 0x2bbb06)
#6  0x00007f96b073d333 _ZN22QGuiApplicationPrivate4initEv (libQt5Gui.so.5 + 0x13d333)
#7  0x00007f96b15741bd _ZN19QApplicationPrivate4initEv (libQt5Widgets.so.5 + 0x1741bd)
#8  0x000055ffc4a71f55 n/a (xdg-desktop-portal-kde + 0x26f55)
#9  0x00007f96af450083 __libc_start_main (libc.so.6 + 0x24083)
#10 0x000055ffc4a7229e n/a (xdg-desktop-portal-kde + 0x2729e)

Stack trace of thread 94613:
#0  0x00007f96af53e99f __GI___poll (libc.so.6 + 0x11299f)
#1  0x00007f96addd736e n/a (libglib-2.0.so.0 + 0x5236e)
#2  0x00007f96addd74a3 g_main_context_iteration (libglib-2.0.so.0 + 0x524a3)
#3  0x00007f96afb0fb82 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x30fb82)
#4  0x00007f96afab3b3b _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2b3b3b)
#5  0x00007f96af8cd342 _ZN7QThread4execEv (libQt5Core.so.5 + 0xcd342)
#6  0x00007f96b057af4b n/a (libQt5DBus.so.5 + 0x18f4b)
#7  0x00007f96af8ce543 _ZN14QThreadPrivate5startEPv (libQt5Core.so.5 + 0xce543)
#8  0x00007f96b137f609 start_thread (libpthread.so.0 + 0x8609)
#9  0x00007f96af54b133 __clone (libc.so.6 + 0x11f133)

also, any help on how to get info out of a hung process would be nice

*** This bug has been marked as a duplicate of bug 460513 ***

(In reply to Jason Playne from comment #1)
> it appears this segfault didn't create a core dump?
> 
> $ coredumpctl
> No coredumps found.

Do you have core dumps enabled? If coredumpctl still returns the same result, they might be disabled.
Places to check: https://wiki.archlinux.org/title/Core_dump, https://linux-audit.com/understand-and-configure-core-dumps-work-on-linux/
- sysctl kernel.core_pattern
- /usr/lib/sysctl.d/50-coredump.conf
- ulimit -c

i have managed to find a coredump

           PID: 248057 (plasmashell)
           UID: 1000 (jason)
           GID: 1000 (jason)
        Signal: 6 (ABRT)
     Timestamp: Sat 2022-10-15 11:20:36 AWST (2 days ago)
  Command Line: plasmashell --replace
    Executable: /usr/bin/plasmashell
 Control Group: /user.slice/user-1000.slice/session-171.scope
          Unit: session-171.scope
         Slice: user-1000.slice
       Session: 171
     Owner UID: 1000 (jason)
       Boot ID: 9123c4115a9743108f1f78feb5e71e19
    Machine ID: 0b8920f9b79a4d7aa86de3faed35fe2d
      Hostname: jason-desktop
       Storage: /var/lib/systemd/coredump/core.plasmashell.1000.9123c4115a9743108f1f78feb5e71e19.248057.1665804036000000000000.lz4
       Message: Process 248057 (plasmashell) of user 1000 dumped core.

                Stack trace of thread 248057:
                #0  0x00007fb5b8a6f00b __GI_raise (libc.so.6 + 0x4300b)
                #1  0x00007fb5b8a4e859 __GI_abort (libc.so.6 + 0x22859)
                #2  0x00007fb5b8e92bd9 qt_message_fatal (libQt5Core.so.5 + 0x92bd9)
                #3  0x00007fb5b9539d9b init_platform (libQt5Gui.so.5 + 0x139d9b)
                #4  0x00007fb5b953a218 _ZN22QGuiApplicationPrivate21createEventDispatcherEv (libQt5Gui.so.5 + 0x13a218)
                #5  0x00007fb5b90bbb06 _ZN23QCoreApplicationPrivate4initEv (libQt5Core.so.5 + 0x2bbb06)
                #6  0x00007fb5b953d333 _ZN22QGuiApplicationPrivate4initEv (libQt5Gui.so.5 + 0x13d333)
                #7  0x00007fb5b9f741bd _ZN19QApplicationPrivate4initEv (libQt5Widgets.so.5 + 0x1741bd)
                #8  0x000055b198773a0d main (plasmashell + 0x28a0d)
                #9  0x00007fb5b8a50083 __libc_start_main (libc.so.6 + 0x24083)
                #10 0x000055b19877491e _start (plasmashell + 0x2991e)

                Stack trace of thread 248058:
                #0  0x00007fb5b8b3e99f __GI___poll (libc.so.6 + 0x11299f)
                #1  0x00007fb5b754336e n/a (libglib-2.0.so.0 + 0x5236e)
                #2  0x00007fb5b75434a3 g_main_context_iteration (libglib-2.0.so.0 + 0x524a3)
                #3  0x00007fb5b910fb82 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x30fb82)
                #4  0x00007fb5b90b3b3b _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2b3b3b)
                #5  0x00007fb5b8ecd342 _ZN7QThread4execEv (libQt5Core.so.5 + 0xcd342)
                #6  0x00007fb5b9c9ef4b n/a (libQt5DBus.so.5 + 0x18f4b)
                #7  0x00007fb5b8ece543 _ZN14QThreadPrivate5startEPv (libQt5Core.so.5 + 0xce543)
                #8  0x00007fb5bb185609 start_thread (libpthread.so.0 + 0x8609)
                #9  0x00007fb5b8b4b133 __clone (libc.so.6 + 0x11f133)

oh and following the documentation I get a slightly more rich output


jason@jason-desktop:~ $ coredumpctl gdb /usr/bin/plasmashell
           PID: 248057 (plasmashell)
           UID: 1000 (jason)
           GID: 1000 (jason)
        Signal: 6 (ABRT)
     Timestamp: Sat 2022-10-15 11:20:36 AWST (2 days ago)
  Command Line: plasmashell --replace
    Executable: /usr/bin/plasmashell
 Control Group: /user.slice/user-1000.slice/session-171.scope
          Unit: session-171.scope
         Slice: user-1000.slice
       Session: 171
     Owner UID: 1000 (jason)
       Boot ID: 9123c4115a9743108f1f78feb5e71e19
    Machine ID: 0b8920f9b79a4d7aa86de3faed35fe2d
      Hostname: jason-desktop
       Storage: /var/lib/systemd/coredump/core.plasmashell.1000.9123c4115a9743108f1f78feb5e71e19.248057.1665804036000000000000.lz4
       Message: Process 248057 (plasmashell) of user 1000 dumped core.

                Stack trace of thread 248057:
                #0  0x00007fb5b8a6f00b __GI_raise (libc.so.6 + 0x4300b)
                #1  0x00007fb5b8a4e859 __GI_abort (libc.so.6 + 0x22859)
                #2  0x00007fb5b8e92bd9 qt_message_fatal (libQt5Core.so.5 + 0x92bd9)
                #3  0x00007fb5b9539d9b init_platform (libQt5Gui.so.5 + 0x139d9b)
                #4  0x00007fb5b953a218 _ZN22QGuiApplicationPrivate21createEventDispatcherEv (libQt5Gui.so.5 + 0x13a218)
                #5  0x00007fb5b90bbb06 _ZN23QCoreApplicationPrivate4initEv (libQt5Core.so.5 + 0x2bbb06)
                #6  0x00007fb5b953d333 _ZN22QGuiApplicationPrivate4initEv (libQt5Gui.so.5 + 0x13d333)
                #7  0x00007fb5b9f741bd _ZN19QApplicationPrivate4initEv (libQt5Widgets.so.5 + 0x1741bd)
                #8  0x000055b198773a0d main (plasmashell + 0x28a0d)
                #9  0x00007fb5b8a50083 __libc_start_main (libc.so.6 + 0x24083)
                #10 0x000055b19877491e _start (plasmashell + 0x2991e)

                Stack trace of thread 248058:
                #0  0x00007fb5b8b3e99f __GI___poll (libc.so.6 + 0x11299f)
                #1  0x00007fb5b754336e n/a (libglib-2.0.so.0 + 0x5236e)
                #2  0x00007fb5b75434a3 g_main_context_iteration (libglib-2.0.so.0 + 0x524a3)
                #3  0x00007fb5b910fb82 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x30fb82)
                #4  0x00007fb5b90b3b3b _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2b3b3b)
                #5  0x00007fb5b8ecd342 _ZN7QThread4execEv (libQt5Core.so.5 + 0xcd342)
                #6  0x00007fb5b9c9ef4b n/a (libQt5DBus.so.5 + 0x18f4b)
                #7  0x00007fb5b8ece543 _ZN14QThreadPrivate5startEPv (libQt5Core.so.5 + 0xce543)
                #8  0x00007fb5bb185609 start_thread (libpthread.so.0 + 0x8609)
                #9  0x00007fb5b8b4b133 __clone (libc.so.6 + 0x11f133)

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Reading symbols from /usr/bin/plasmashell...
Reading symbols from /usr/lib/debug/.build-id/22/87b8620679417738a0acf1dba04885bb86a4bb.debug...
[New LWP 248057]
[New LWP 248058]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `plasmashell --replace'.
Program terminated with signal SIGABRT, Aborted.
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50      ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
[Current thread is 1 (Thread 0x7fb5b4f572c0 (LWP 248057))]
(gdb) bt
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007fb5b8a4e859 in __GI_abort () at abort.c:79
#2  0x00007fb5b8e92bd9 in qt_message_fatal (context=..., message=<synthetic pointer>...) at global/qlogging.cpp:1914
#3  QMessageLogger::fatal (this=this@entry=0x7ffecbcb36f0, msg=msg@entry=0x7fb5b99f9a05 "%s") at global/qlogging.cpp:893
#4  0x00007fb5b9539d9b in init_platform (argv=<optimised out>, argc=@0x7ffecbcb395c: 2, platformThemeName=..., platformPluginPath=..., pluginNamesWithArguments=...)
    at ../../include/QtCore/../../src/corelib/tools/qarraydata.h:209
#5  QGuiApplicationPrivate::createPlatformIntegration (this=0x55b199512d60) at kernel/qguiapplication.cpp:1484
#6  0x00007fb5b953a218 in QGuiApplicationPrivate::createEventDispatcher (this=<optimised out>) at kernel/qguiapplication.cpp:1501
#7  0x00007fb5b90bbb06 in QCoreApplicationPrivate::init (this=this@entry=0x55b199512d60) at kernel/qcoreapplication.cpp:853
#8  0x00007fb5b953d333 in QGuiApplicationPrivate::init (this=this@entry=0x55b199512d60) at kernel/qguiapplication.cpp:1530
#9  0x00007fb5b9f741bd in QApplicationPrivate::init (this=0x55b199512d60) at kernel/qapplication.cpp:513
#10 0x000055b198773a0d in main (argc=<optimised out>, argv=0x7ffecbcb3b48) at ./shell/main.cpp:75

(In reply to space9301 from comment #9)
> (In reply to Jason Playne from comment #1)
> > it appears this segfault didn't create a core dump?
> > 
> > $ coredumpctl
> > No coredumps found.
> 
> Do you have core dumps enabled? If coredumpctl still returns the same
> result, they might be disabled.
> Places to check: https://wiki.archlinux.org/title/Core_dump,
> https://linux-audit.com/understand-and-configure-core-dumps-work-on-linux/
> - sysctl kernel.core_pattern
> - /usr/lib/sysctl.d/50-coredump.conf
> - ulimit -c

Thank you for the help, I did install coredumpctl after the first crashes, and one of of the subsequent ones did produce something. Thank you for making me look again!

Thank you!