Created attachment 187782 [details]
Full backtrace

SUMMARY

Installed fresh Arch Linux with everything latest and while interacting with panel it froze/got stuck.

STEPS TO REPRODUCE
1. No idea, happened only once

OBSERVED RESULT

Plasma froze

EXPECTED RESULT

Not to freeze :)

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.5.3
KDE Frameworks Version: 6.20.0
Qt Version: 6.10.1

ADDITIONAL INFORMATION

I'm putting this here mostly for documentation purposes because it happened only once and since then there's been bunch of updates.
It could have been Mesa 25.2.7 bug.

```
$ journalctl --user -u plasma-plasmashell.service --no-pager
dec 03 18:24:57 Arch systemd[1516]: Starting KDE Plasma Workspace...
dec 03 18:24:57 Arch systemd[1516]: Started KDE Plasma Workspace.
dec 03 18:24:59 Arch plasmashell[1827]: Applet preload policy set to 1
dec 03 18:25:00 Arch plasmashell[1827]: requesting unexisting screen geometry -1
dec 03 18:25:05 Arch plasmashell[1827]: Activity added twice "8bbeb32b-92fa-465e-99e4-3b3eb5f74047"
dec 03 18:25:05 Arch plasmashell[1827]: Failed to register with host portal QDBusError("org.freedesktop.portal.Error.Failed", "Could not register app ID: Connection already associated with an application ID")
dec 03 18:25:07 Arch plasmashell[1827]: Entry is not valid "org.kde.kontact.desktop" 0x5577b20bd940
dec 03 18:25:07 Arch plasmashell[1827]: Entry is not valid "org.kde.discover.desktop" 0x5577b2092cb0
dec 03 18:25:12 Arch plasmashell[1827]: Entry is not valid "org.kde.kontact.desktop" 0x5577b2119dd0
dec 03 18:25:12 Arch plasmashell[1827]: Entry is not valid "org.kde.discover.desktop" 0x5577b2a4e2c0
dec 03 18:25:12 Arch plasmashell[1827]: Entry is not valid "org.kde.kontact.desktop" 0x5577b2a4e2c0
dec 03 18:25:12 Arch plasmashell[1827]: Entry is not valid "org.kde.discover.desktop" 0x5577b322ae70
dec 03 18:25:13 Arch plasmashell[1827]: No object for name "alsa_output.pci-0000_0c_00.3.iec958-stereo.monitor"
dec 03 18:25:17 Arch plasmashell[1827]: error connecting to kameleon via dbus: "No such object path '/modules/kameleon'"
dec 03 18:25:31 Arch plasmashell[1827]: The cached device pixel ratio value was stale on window update.  Please file a QTBUG which explains how to reproduce.
```

```
[...]
Thread 50 (Thread 0x7f028b1f66c0 (LWP 2186) "QSGRenderThread"):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007f02a9d5daeb in sys_futex () at ../mesa-25.2.7/src/util/futex.c:43
#2  futex_wait () at ../mesa-25.2.7/src/util/futex.c:55
#3  0x00007f02a9d40bd0 in simple_mtx_lock () at ../mesa-25.2.7/src/util/simple_mtx.h:117
#4  _eglLockDisplay () at ../mesa-25.2.7/src/egl/main/eglapi.c:288
#5  0x00007f02a9d4417d in eglSwapInterval () at ../mesa-25.2.7/src/egl/main/eglapi.c:1382
#6  0x00007f02aacdc89f in QtWaylandClient::QWaylandGLContext::swapBuffers (this=0x7f02683f7280, surface=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/plugins/hardwareintegration/wayland-egl/qwaylandglcontext.cpp:471
#7  0x00007f02b25b78cd in QRhiGles2::endFrame (this=0x7f0268001910, swapChain=0x7f0268767780, flags=...) at /usr/src/debug/qt6-base/qtbase/src/gui/rhi/qrhigles2.cpp:2351
#8  0x00007f02b2405ddf in QRhi::endFrame (this=0x7f02680024a0, swapChain=0x7f0268767780, flags=..., flags@entry=...) at /usr/src/debug/qt6-base/qtbase/src/gui/rhi/qrhi.cpp:11507
#9  0x00007f02b3685ca0 in QSGRenderThread::syncAndRender (this=<optimized out>) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgthreadedrenderloop.cpp:788
#10 QSGRenderThread::run (this=0x7f02a0002fe0) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgthreadedrenderloop.cpp:992
#11 0x00007f02b1b2f899 in operator() (__closure=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:437
#12 (anonymous namespace)::terminate_on_exception<QThreadPrivate::start(void*)::<lambda()> > (t=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:367
#13 QThreadPrivate::start (arg=0x7f02a0002fe0) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:397
#14 0x00007f02b109698b in start_thread (arg=<optimized out>) at pthread_create.c:448
#15 0x00007f02b111a9cc in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

[...]

Thread 33 (Thread 0x7f020ffff6c0 (LWP 2322) "QSGRenderThread"):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007f02a9d5daeb in sys_futex () at ../mesa-25.2.7/src/util/futex.c:43
#2  futex_wait () at ../mesa-25.2.7/src/util/futex.c:55
#3  0x00007f02a9d40bd0 in simple_mtx_lock () at ../mesa-25.2.7/src/util/simple_mtx.h:117
#4  _eglLockDisplay () at ../mesa-25.2.7/src/egl/main/eglapi.c:288
#5  0x00007f02a9d44507 in eglSwapBuffers () at ../mesa-25.2.7/src/egl/main/eglapi.c:1421
#6  0x00007f02aacdc93a in QtWaylandClient::QWaylandGLContext::swapBuffers (this=0x7f0208002740, surface=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/plugins/hardwareintegration/wayland-egl/qwaylandglcontext.cpp:478
#7  0x00007f02b25b78cd in QRhiGles2::endFrame (this=0x7f0208001910, swapChain=0x7f0208363a30, flags=...) at /usr/src/debug/qt6-base/qtbase/src/gui/rhi/qrhigles2.cpp:2351
#8  0x00007f02b2405ddf in QRhi::endFrame (this=0x7f02080024a0, swapChain=0x7f0208363a30, flags=..., flags@entry=...) at /usr/src/debug/qt6-base/qtbase/src/gui/rhi/qrhi.cpp:11507
#9  0x00007f02b3685ca0 in QSGRenderThread::syncAndRender (this=<optimized out>) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgthreadedrenderloop.cpp:788
#10 QSGRenderThread::run (this=0x7f02a0005f20) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgthreadedrenderloop.cpp:992
#11 0x00007f02b1b2f899 in operator() (__closure=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:437
#12 (anonymous namespace)::terminate_on_exception<QThreadPrivate::start(void*)::<lambda()> > (t=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:367
#13 QThreadPrivate::start (arg=0x7f02a0005f20) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:397
#14 0x00007f02b109698b in start_thread (arg=<optimized out>) at pthread_create.c:448
#15 0x00007f02b111a9cc in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

[...]

Thread 1 (Thread 0x7f02aad46080 (LWP 1827) "plasmashell"):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007f0299712f3b in sys_futex () at ../mesa-25.2.7/src/util/futex.c:43
#2  futex_wait () at ../mesa-25.2.7/src/util/futex.c:55
#3  0x00007f0299720523 in do_futex_fence_wait () at ../mesa-25.2.7/src/util/u_queue.c:131
#4  0x00007f029972174c in _util_queue_fence_wait () at ../mesa-25.2.7/src/util/u_queue.c:146
#5  util_queue_fence_wait () at ../mesa-25.2.7/src/util/u_queue.h:181
#6  util_queue_fence_wait () at ../mesa-25.2.7/src/util/u_queue.h:178
#7  util_queue_finish () at ../mesa-25.2.7/src/util/u_queue.c:722
#8  0x00007f0299ba9f6b in si_set_debug_callback () at ../mesa-25.2.7/src/gallium/drivers/radeonsi/si_pipe.c:449
#9  0x00007f0299baa808 in si_destroy_context () at ../mesa-25.2.7/src/gallium/drivers/radeonsi/si_pipe.c:202
#10 0x00007f0299966892 in tc_destroy () at ../mesa-25.2.7/src/gallium/auxiliary/util/u_threaded_context.c:5400
#11 0x00007f02992dbcf2 in st_destroy_context_priv () at ../mesa-25.2.7/src/mesa/state_tracker/st_context.c:356
#12 0x00007f02992dd832 in st_destroy_context () at ../mesa-25.2.7/src/mesa/state_tracker/st_context.c:967
#13 0x00007f029923e370 in dri_destroy_context () at ../mesa-25.2.7/src/gallium/frontends/dri/dri_context.c:267
#14 0x00007f02a9d5003a in dri2_destroy_context () at ../mesa-25.2.7/src/egl/drivers/dri2/egl_dri2.c:1271
#15 dri2_destroy_context () at ../mesa-25.2.7/src/egl/drivers/dri2/egl_dri2.c:1266
#16 0x00007f02a9d4254b in eglDestroyContext () at ../mesa-25.2.7/src/egl/main/eglapi.c:919
#17 0x00007f02aacd9d31 in QtWaylandClient::QWaylandGLContext::~QWaylandGLContext (this=<optimized out>, this=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/plugins/hardwareintegration/wayland-egl/qwaylandglcontext.cpp:319
#18 0x00007f02aacd9d86 in QtWaylandClient::QWaylandGLContext::~QWaylandGLContext (this=<optimized out>, this=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/plugins/hardwareintegration/wayland-egl/qwaylandglcontext.cpp:320
#19 0x00007f02b259cabe in QOpenGLContext::destroy (this=0x7ffc0d920610) at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qopenglcontext.cpp:461
#20 0x00007f02b25ab614 in QOpenGLContext::~QOpenGLContext (this=<optimized out>, this=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qopenglcontext.cpp:488
#21 QRhiGles2InitParams::newFallbackSurface (format=...) at /usr/src/debug/qt6-base/qtbase/src/gui/rhi/qrhigles2.cpp:633
#22 0x00007f02b3691dfc in QSGRhiSupport::maybeCreateOffscreenSurface (this=<optimized out>, window=0x5577b3b89660) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgrhisupport.cpp:901
#23 QSGRhiSupport::maybeCreateOffscreenSurface (this=0x7f02b3927fb0 <_ZZN13QSGRhiSupport17instance_internalEvE4inst.lto_priv.0>, window=0x5577b3b89660) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgrhisupport.cpp:895
#24 QSGThreadedRenderLoop::handleExposure (this=<optimized out>, window=<optimized out>) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgthreadedrenderloop.cpp:1331
#25 QSGThreadedRenderLoop::exposureChanged (this=<optimized out>, window=<optimized out>) at /usr/src/debug/qt6-declarative/qtdeclarative/src/quick/scenegraph/qsgthreadedrenderloop.cpp:1265
#26 0x00007f02b22157ac in QWindow::event (this=<optimized out>, ev=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qwindow.cpp:2737
#27 0x00007f02b3b021c0 in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x5577b3b89660, e=0x7ffc0d920920) at /usr/src/debug/qt6-base/qtbase/src/widgets/kernel/qapplication.cpp:3305
#28 0x00007f02b196a958 in QCoreApplication::notifyInternal2 (receiver=0x5577b3b89660, event=0x7ffc0d920920) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1109
#29 0x00007f02b196a9ad in QCoreApplication::sendSpontaneousEvent (receiver=<optimized out>, event=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1563
#30 0x00007f02b21ab0ea in QGuiApplicationPrivate::processExposeEvent (e=0x7ffc0d9209d0) at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qguiapplication.cpp:3477
#31 0x00007f02b2220ccd in QWindowSystemEventHandler::sendEvent (this=<optimized out>, e=0x7ffc0d9209d0) at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qwindowsysteminterface.cpp:190
#32 QWindowSystemHelper<QWindowSystemInterface::SynchronousDelivery>::handleEvent<QWindowSystemInterfacePrivate::ExposeEvent, QWindow*, QRegion> () at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qwindowsysteminterface.cpp:102
#33 QWindowSystemHelper<QWindowSystemInterface::SynchronousDelivery>::handleEvent<QWindowSystemInterfacePrivate::ExposeEvent, QWindow*, QRegion> () at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qwindowsysteminterface.cpp:96
#34 handleWindowSystemEvent<QWindowSystemInterfacePrivate::ExposeEvent, QWindowSystemInterface::SynchronousDelivery, QWindow*, QRegion> () at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qwindowsysteminterface.cpp:138
#35 QWindowSystemInterface::handleExposeEvent<QWindowSystemInterface::SynchronousDelivery> (window=0x5577b3b89660, region=...) at /usr/src/debug/qt6-base/qtbase/src/gui/kernel/qwindowsysteminterface.cpp:341
#36 0x00007f02b2b1cfff in QtWaylandClient::QWaylandWindow::sendExposeEvent (this=this@entry=0x5577b13a3680, rect=...) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/qwaylandwindow.cpp:607
#37 0x00007f02b2b1e8de in QtWaylandClient::QWaylandWindow::updateExposure (this=0x5577b13a3680) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/qwaylandwindow.cpp:1624
#38 0x00007f02b4153ac6 in ffi_call_unix64 () at ../src/x86/unix64.S:104
#39 0x00007f02b415076b in ffi_call_int (cif=cif@entry=0x7ffc0d920c80, fn=fn@entry=0x7f02b4873960 <QtWayland::xdg_surface::handle_configure(void*, xdg_surface*, unsigned int)>, rvalue=<optimized out>, rvalue@entry=0x0, avalue=avalue@entry=0x7ffc0d920d50, closure=closure@entry=0x0) at ../src/x86/ffi64.c:676
#40 0x00007f02b415306e in ffi_call (cif=cif@entry=0x7ffc0d920c80, fn=0x7f02b4873960 <QtWayland::xdg_surface::handle_configure(void*, xdg_surface*, unsigned int)>, rvalue=rvalue@entry=0x0, avalue=avalue@entry=0x7ffc0d920d50) at ../src/x86/ffi64.c:713
#41 0x00007f02b453348d in wl_closure_invoke (closure=closure@entry=0x7f029c009500, target=<optimized out>, target@entry=0x5577b2e08ac0, opcode=opcode@entry=0, data=<optimized out>, flags=1) at ../wayland-1.24.0/src/connection.c:1241
#42 0x00007f02b45342e9 in dispatch_event (display=display@entry=0x5577b10af440, queue=queue@entry=0x5577b10af538) at ../wayland-1.24.0/src/wayland-client.c:1707
#43 0x00007f02b45346f3 in dispatch_queue (display=0x5577b10af440, queue=0x5577b10af538) at ../wayland-1.24.0/src/wayland-client.c:1853
#44 wl_display_dispatch_queue_pending (display=0x5577b10af440, queue=0x5577b10af538) at ../wayland-1.24.0/src/wayland-client.c:2190
#45 0x00007f02b2ae10c6 in QtWaylandClient::QWaylandDisplay::flushRequests (this=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/plugins/platforms/wayland/qwaylanddisplay.cpp:230
#46 0x00007f02b19d771a in doActivate<false> (sender=<optimized out>, signal_index=<optimized out>, argv=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qobject.cpp:4269
#47 0x00007f02b1c48195 in QAbstractEventDispatcher::awake (this=0x5577b10acd30) at /usr/src/debug/qt6-base/build/src/corelib/Core_autogen/include/moc_qabstracteventdispatcher.cpp:128
#48 QEventDispatcherGlib::processEvents (this=0x5577b10acd30, flags=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventdispatcher_glib.cpp:406
#49 0x00007f02b1975786 in QEventLoop::processEvents (this=0x7ffc0d9210f0, flags=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventloop.cpp:104
#50 QEventLoop::exec (this=0x7ffc0d9210f0, flags=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventloop.cpp:186
#51 0x00007f02b196f3f1 in QCoreApplication::exec () at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1452
#52 0x00007f02b3afd32a in QApplication::exec () at /usr/src/debug/qt6-base/qtbase/src/widgets/kernel/qapplication.cpp:2575
#53 0x000055778e0ef2d9 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/plasma-workspace/plasma-workspace-6.5.3/shell/main.cpp:188
```