Created attachment 152873 [details] Output of journalctl /usr/bin/kwin_wayland, including crashes SUMMARY *** NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols. See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports *** STEPS TO REPRODUCE 1. Unknown (played some steam games, ~a few hours before this happened) 2. 3. OBSERVED RESULT Plasma shell crashes and fails to reload. The first time, it was able to remain open as long as I didn't use the application launcher. I relaunched manually with kstart plasmashell. Then, eventually, it failed to work at all, just giving ```Omitting both --window and --windowclass arguments is not recommended The Wayland connection broke. Did the Wayland compositor die?``` (tangent/another annoyance: the application launcher seems to remain open whenever I launch anything, needing to be manually closed) I then killed kwin_wayland. It restarted automatically. The second time, when plasmashell crashed, it relaunched automatically, quickly dying. In the logs, `journalctl /usr/bin/kwin_wayland`, ```Oct 16 01:05:02 archlinux kwin_wayland_wrapper[1962]: Data too big for buffer (4108 > 4096). Oct 16 01:05:02 archlinux kwin_wayland_wrapper[1962]: error in client communication (pid 66420) ``` is written at the time of the crash. EXPECTED RESULT Plasmashell doesn't die. And, if it does die, I can restart it manually as on X11. This is extremely frustrating as I have to restart my entire session to get the taskbar/launcher back. SOFTWARE/OS VERSIONS Linux/KDE Plasma: (available in About System) KDE Plasma Version: KDE Frameworks Version: Qt Version: ADDITIONAL INFORMATION This is my first bug report. It will be incomplete/imperfect due to the difficulty of writing anything. I don't know how to attach a backtrace yet. While writing, I also seem to have lost alt-tab functionality. Attaching the output of `journalctl /usr/bin/kwin_wayland`. I also have the output for plasmashell, but I can't seem to upload two attachments.
Created attachment 152874 [details] Output of journalctl /usr/bin/plasmashell, including crashes
for completeness/readability: Operating System: Arch Linux KDE Plasma Version: 5.26.0 KDE Frameworks Version: 5.99.0 Qt Version: 5.15.6 Kernel Version: 6.0.1-arch2-1 (64-bit) Graphics Platform: Wayland
quick question - when kwin_wayland crashes, does it just leave you with a black screen + movable cursor?
(In reply to Jason Playne from comment #3) > quick question - when kwin_wayland crashes, does it just leave you with a > black screen + movable cursor? To clarify, kwin_wayland didn't crash - I killed it manually. But yes, I just got a black screen + movable cursor. (testing this now after killing plasmashell, I get the same)
I managed to generate a backtrace by recompiling the plasma-workspace package with options=(debug !strip), and using gdb -p $(pidof plasmashell) --command=debug-script debug-script: ```set logging file plasmashell.gdb set logging enabled break checkWaylandError(wl_display*) continue # backtrace bt # generate coredump gcore ``` (I identified the source of the message "The Wayland connection broke. Did the Wayland compositor die?" with `strings --print-file-name *.so* | grep -i 'compositor die?'`, traced it to libQt5WaylandClient.so, and downloaded+searched the source for that string. The function is https://github.com/qt/qtwayland/blob/2303ee38ead0a4eafa9f8af629fd8495c45d1442/src/client/qwaylanddisplay.cpp#L66 static void checkWaylandError(struct wl_display *display)) Thread 1 "plasmashell" hit Breakpoint 1, checkWaylandError (display=0x55b3ab934160) at /usr/src/debug/qtwayland/src/client/qwaylanddisplay.cpp:91 91 { #0 checkWaylandError(wl_display*) (display=0x55b3ab934160) at /usr/src/debug/qtwayland/src/client/qwaylanddisplay.cpp:91 #1 0x00007fb211122b7c in QtWaylandClient::EventThread::readAndDispatchEvents() (this=<optimized out>) at /usr/src/debug/qtwayland/src/client/qwaylanddisplay.cpp:141 #2 QtWaylandClient::QWaylandDisplay::flushRequests() (this=<optimized out>) at /usr/src/debug/qtwayland/src/client/qwaylanddisplay.cpp:419 #3 0x00007fb2106b0520 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5 #4 0x00007fb211378b1c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5 #5 0x00007fb21068cb88 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5 #6 0x00007fb21068d693 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/libQt5Core.so.5 #7 0x00007fb2106d3728 in () at /usr/lib/libQt5Core.so.5 #8 0x00007fb20ed1981b in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0 #9 0x00007fb20ed6fec9 in () at /usr/lib/libglib-2.0.so.0 #10 0x00007fb20ed180d2 in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0 #11 0x00007fb2106d750c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #12 0x00007fb21068532c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5 #13 0x00007fb21068fe59 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5 #14 0x000055b3ab3521a3 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/plasma-workspace-5.26.0/shell/main.cpp:233 warning: Memory read failed for corefile section, 4096 bytes at 0xffffffffff600000. Saved corefile core.158040 I'm not sure how useful this is. I also recompiled+installed the package qt5-wayland, which may explain the source file in the backtrace #0 checkWaylandError(wl_display*) (display=0x55b3ab934160) at /usr/src/debug/qtwayland/src/client/qwaylanddisplay.cpp:91 instead of a binary #3 0x00007fb2106b0520 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5 I don't know which way is preferred for debugging.
*** Bug 460336 has been marked as a duplicate of this bug. ***
(In reply to Jason Playne from comment #6) > *** Bug 460336 has been marked as a duplicate of this bug. *** I'm not sure this is a duplicate. For me, my programs remained open -- only plasmashell crashed. They were only lost when I killed kwin_wayland. There were no segfaults in either kwin_wayland or plasmashell. To reproduce the black screen with movable cursor: - killall plasmashell (the screen is now black, as the desktop background is handled by plasmashell, but all the programs are open. In the original bug, plasmashell failed to relaunch) - ps $(pgrep kwin_wayland) PID TTY STAT TIME COMMAND 220965 ? Ssl 0:00 /usr/bin/kwin_wayland_wrapper --xwayland 237394 ? Sl 0:02 /usr/bin/kwin_wayland --wayland-fd 7 --socket wayland-0 --xwayland-fd 8 --xwayland-fd 9 - killall kwin_wayland (the screen is black, and all the programs are gone, but I can still move my cursor and launch a terminal with ctrl-alt-t) - ps $(pgrep kwin_wayland) PID TTY STAT TIME COMMAND 220965 ? Ssl 0:00 /usr/bin/kwin_wayland_wrapper --xwayland 238586 ? Sl 0:02 /usr/bin/kwin_wayland --wayland-fd 7 --socket wayland-0 --xwayland-fd 8 --xwayland-fd 9 (kwin_wayland has automatically been restarted. Killing kwin_wayland_wrapper gets me to the login screen) - kstart plasmashell (I can now use my session again) Sorry if the original bug description was misleading. "Output of journalctl /usr/bin/kwin_wayland, including crashes" should have been "including crashes of plasmashell".
(In reply to space9301 from comment #7) > (In reply to Jason Playne from comment #6) > > *** Bug 460336 has been marked as a duplicate of this bug. *** > > I'm not sure this is a duplicate. For me, my programs remained open -- only > plasmashell crashed. They were only lost when I killed kwin_wayland. There > were no segfaults in either kwin_wayland or plasmashell. > > To reproduce the black screen with movable cursor: > - killall plasmashell (the screen is now black, as the desktop background > is handled by plasmashell, but all the programs are open. In the original > bug, plasmashell failed to relaunch) > - ps $(pgrep kwin_wayland) > PID TTY STAT TIME COMMAND > 220965 ? Ssl 0:00 /usr/bin/kwin_wayland_wrapper --xwayland > 237394 ? Sl 0:02 /usr/bin/kwin_wayland --wayland-fd 7 --socket > wayland-0 --xwayland-fd 8 --xwayland-fd 9 > - killall kwin_wayland (the screen is black, and all the programs are > gone, but I can still move my cursor and launch a terminal with ctrl-alt-t) > - ps $(pgrep kwin_wayland) > PID TTY STAT TIME COMMAND > 220965 ? Ssl 0:00 /usr/bin/kwin_wayland_wrapper --xwayland > 238586 ? Sl 0:02 /usr/bin/kwin_wayland --wayland-fd 7 --socket > wayland-0 --xwayland-fd 8 --xwayland-fd 9 > (kwin_wayland has automatically been restarted. Killing kwin_wayland_wrapper > gets me to the login screen) > - kstart plasmashell (I can now use my session again) > > Sorry if the original bug description was misleading. "Output of journalctl > /usr/bin/kwin_wayland, including crashes" should have been "including > crashes of plasmashell". Your description describes what I am seeing (better than I am able to put into words) The segfault's and back traces I have seen I am thinking are incidental. I believe what I see is what you are describing. I suddenly get a back screen with a movable cursor, kwin_wayland is still running - lots of complains from the apps about losing their connection to the wayland server. I *think* the apps are still alive - I work around the problem with restarting sddm (the big hammer approach)
Yes, it does look similar, though the cause is different. A few things: - you reported a segfault in kwin_wayland, i.e. it tried to access invalid memory, then crashed. This is not incidental to what you experienced, it is the bug. - kwin_wayland is not still running, it restarted. Note the different process IDs, 237394 vs 238586 - maybe other programs are still running after the crash, but I don't see them either. You would have to take a process tree before the crash with something like `ps axjf` and log to a file, then compare with after. I'm happy to try to help you to reproduce your bug, though I do have limited time to spend on this now. I'll move further discussion over there.
Adding in some notes (to see if my usage patterns jive with yours) I have 3 virtual desktops. When I primarily use just one of them (#3) the issue does not manifest When I am regularly switching between each the problem manifests (but not on change) On each desktop I have #1 Java XWayland (jetbrains ide) + Opera Web Browser (Wayland) #2 Vivaldi (Wayland) and Teams (X11, Electron) #3 Discord (X11) and Firefox (X11) I am wondering if this might be a Chromium/Wayland caused thing?