I have found a way to crash kwin/plasma in Kubuntu 16.04.1 on my system (pentium g860, 8Gb, integrated video) and in Virtual Box. The method works in freshly installed VM, live CD VM, live USB my system, and in my installed system (which is based on ppa:kubuntu-ppa/backports). In a fteshly installed VM system the result is a report about plasma crash that instantly closes. In live CD vm system and live USB VM systems kwin obviously crashes but there is no report appear. In my real system a report about a kwin crash appears. Reproducible: Always Steps to Reproduce: 1. boot the system (live usb/cd Kubuntu 16.04.1, freshly insalled Kubuntu 16.04.1, VM or may be your real system) 2. Press: Application Launcher - Applications - Settings -System Settings - Applications Style - Window Decorations - Select Plastic - Apply 3. Press: All Settings (the back button) - Input Devices - Touchpad - Joystic (or other tab, or back) - Discard 4. Close the System Settings window by clicking on the "X" close button 5. Do again: Application Launcher - Applications - Settings -System Settings - Input Devices - Touchpad - Joystic (or other tab, or back) => KWin crash If you open any other windows before or inbetween, the method may not work. Actual Results: In my real system (kubuntu backport) a report about kwin crash appears In a freshly installed VM system after right clicking on the task button and trying to close the System Settings window for a couple of times a plasma crash report appears and instantly closes. The System Settings window doesn't close. In live cd/usb systems nothing appears but I couldn't close the System Settings window in a usual way because it had no caption and nothing happend when I tried to close it by the method above.. Expected Results: the window about applying changes appears as usual and the System Settings window can be closed in a usual way Processor: 2x Intel(R) Pentium(R) CPU G860 @ 3.00GHz Memory : 7852MB Integrated Video Operating System: Kubuntu 16.04.1 LTS ppa:kubuntu-ppa/backports
If you are able to reproduce please provide the backtrace from drkonqi.
In live cd/usb systems (Kubuntu 16.04.1) no crash report appears. Such a behavior could be done intentionally. The caption of the System Settings window disappears, so I think it is obvious that kwin crashes. I couldn't close the System Settings window using the task manager button. Nothing happened. Plasma didn't crash. I can't or don't know how to provide a backtrace of crashed kwin because no crash report appears. In a freshly installed VM system. (HOST: Kubuntu 16.04.1 LTS ppa:kubuntu-ppa/backports, Virtual Box 5.0.24_Ubuntu r108355, GUEST: Virtual machine Ram 2048, Kubuntu 16.04.1 LTS, sha256sum -b kubuntu-16.04.1-desktop-amd64.iso e97fbadd3219ef41a77aa801bdb52e9a4f3deb3449fcd08d465f865c6b751b3d) it doesn't show a kwin crash report but the caption of the System Settings window disappears, so I think it is obvious that kwin crashed. I can't or don't know how to provide a backtrace of the crashed kwin. After right clicking on the task manager button and trying to close the System Settings window for a couple of times a plasma crash report appears and instantly closes. Such a behavior could be done intentionally. I can't or don't know how to provide a backtrace of the crashed plasma. In my system that is based on Kubuntu 16.04.1 LTS ppa:kubuntu-ppa/backports I can generate a backtrace of crashed kwin, but I couldn't guess packages with debugging symbols for /usr/bin/kwin_x11 /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5 /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 The ppa:kubuntu-ppa/backports doesn't have libkf5windowsystem5-dbg. (I installed kwin-dbg libqt5declarative5 qtbase5-dbg qtquick1-5-dbg) Application: kwin_x11 (5.6.5) Qt Version: 5.5.1 Frameworks Version: 5.23.0 Operating System: Linux 4.4.0-31-generic x86_64 Distribution: Ubuntu 16.04.1 LTS -- Information about the crash: <Напишите подробно, что вы делали, когда произошла ошибка.> The crash can be reproduced every time. -- Backtrace: A useful backtrace could not be generated Application: KWin (kwin_x11), signal: Segmentation fault Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". [Current thread is 1 (Thread 0x7f4e3c9e6940 (LWP 3154))] Thread 4 (Thread 0x7f4d80e16700 (LWP 3560)): #0 0x00007f4e3accebe1 in QEventDispatcherUNIXPrivate::doSelect (this=this@entry=0x7f4d7c09ed60, flags=..., flags@entry=..., timeout=timeout@entry=0x0) at kernel/qeventdispatcher_unix.cpp:192 #1 0x00007f4e3accf13e in QEventDispatcherUNIX::processEvents (this=0x7f4d7c051b40, flags=...) at kernel/qeventdispatcher_unix.cpp:607 #2 0x00007f4e3ac78dea in QEventLoop::exec (this=this@entry=0x7f4d80e15c60, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204 #3 0x00007f4e3aa958a4 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503 #4 0x00007f4e353553c5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 #5 0x00007f4e3aa9a84e in QThreadPrivate::start (arg=0x214d770) at thread/qthread_unix.cpp:331 #6 0x00007f4e361f96fa in start_thread (arg=0x7f4d80e16700) at pthread_create.c:333 #7 0x00007f4e3c4eab5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 3 (Thread 0x7f4e0e75e700 (LWP 3244)): #0 pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f4e39c1ebd4 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5 #2 0x00007f4e39c1ec19 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5 #3 0x00007f4e361f96fa in start_thread (arg=0x7f4e0e75e700) at pthread_create.c:333 #4 0x00007f4e3c4eab5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 2 (Thread 0x7f4e154ef700 (LWP 3223)): #0 0x00007f4e3c4e0d13 in select () at ../sysdeps/unix/syscall-template.S:84 #1 0x00007f4e3accd10f in qt_safe_select (nfds=18, fdread=fdread@entry=0x7f4e08000a78, fdwrite=fdwrite@entry=0x7f4e08000d08, fdexcept=fdexcept@entry=0x7f4e08000f98, orig_timeout=orig_timeout@entry=0x0) at kernel/qcore_unix.cpp:75 #2 0x00007f4e3accec0e in QEventDispatcherUNIX::select (timeout=0x0, exceptfds=0x7f4e08000f98, writefds=0x7f4e08000d08, readfds=0x7f4e08000a78, nfds=<optimized out>, this=0x7f4e080008c0) at kernel/qeventdispatcher_unix.cpp:320 #3 QEventDispatcherUNIXPrivate::doSelect (this=this@entry=0x7f4e080008e0, flags=..., flags@entry=..., timeout=timeout@entry=0x0) at kernel/qeventdispatcher_unix.cpp:196 #4 0x00007f4e3accf13e in QEventDispatcherUNIX::processEvents (this=0x7f4e080008c0, flags=...) at kernel/qeventdispatcher_unix.cpp:607 #5 0x00007f4e3ac78dea in QEventLoop::exec (this=this@entry=0x7f4e154eec60, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204 #6 0x00007f4e3aa958a4 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503 #7 0x00007f4e353553c5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 #8 0x00007f4e3aa9a84e in QThreadPrivate::start (arg=0x13bd140) at thread/qthread_unix.cpp:331 #9 0x00007f4e361f96fa in start_thread (arg=0x7f4e154ef700) at pthread_create.c:333 #10 0x00007f4e3c4eab5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 1 (Thread 0x7f4e3c9e6940 (LWP 3154)): [KCrash Handler] #6 0x00007f4e3526e6d5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 #7 0x00007f4e35215685 in QV4::ExecutionEngine::newStringObject(QV4::Value const&) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 #8 0x00007f4e352ae8b2 in QV4::Runtime::getProperty(QV4::ExecutionEngine*, QV4::Value const&, int) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 #9 0x00007f4e0c07cc79 in ?? () #10 0x00007f4e35a83e62 in QQuickItem::staticMetaObject () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5 #11 0x00007f4d7b801260 in ?? () #12 0x0000000002018440 in ?? () #13 0x00007f4d7b801258 in ?? () #14 0x00000000025f8be0 in ?? () #15 0x00007f4e3afe0059 in QVariantConstructor<(anonymous namespace)::GuiTypesFilter>::CallConstructor<QIcon, true>::CallConstructor (this=<synthetic pointer>, tc=<synthetic pointer>) at ../../include/QtCore/5.5.1/QtCore/private/../../../../../src/corelib/kernel/qvariant_p.h:339 #16 QVariantConstructor<(anonymous namespace)::GuiTypesFilter>::FilteredConstructor<QIcon, true>::FilteredConstructor (this=<optimized out>, tc=<synthetic pointer>) at ../../include/QtCore/5.5.1/QtCore/private/../../../../../src/corelib/kernel/qvariant_p.h:362 #17 QVariantConstructor<(anonymous namespace)::GuiTypesFilter>::delegate<QIcon> (this=<synthetic pointer>) at ../../include/QtCore/5.5.1/QtCore/private/../../../../../src/corelib/kernel/qvariant_p.h:383 #18 QMetaTypeSwitcher::switcher<void, QVariantConstructor<(anonymous namespace)::GuiTypesFilter> > (data=0x0, type=<optimized out>, logic=<synthetic pointer>) at ../../include/QtCore/5.5.1/QtCore/private/../../../../../src/corelib/kernel/qmetatypeswitcher_p.h:68 #19 (anonymous namespace)::construct (x=0x24b08c0, copy=0x7ffccbfea9a0) at kernel/qguivariant.cpp:101 #20 0x00000000025f8be0 in ?? () #21 0x00000000025f8be0 in ?? () #22 0x00000000024e6c58 in ?? () #23 0x0000000000000003 in ?? () #24 0x0000000001f56420 in ?? () #25 0x00007f4e354972a0 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5 #26 0x00007f4d7b8011f8 in ?? () #27 0x00000000025f8be0 in ?? () #28 0x00007ffccbfeaf60 in ?? () #29 0x00007f4e0c1b7570 in ?? () #30 0x0000000000000000 in ?? ()
As a workaround use the breeze window decoration. *** This bug has been marked as a duplicate of bug 351839 ***
I should have used search. Sorry for posting duplicates.