UI freezes permanently with open Macro Development window and event listening plugin

[martinjankoehler]

Steps to reproduce

• KLayout 0.30.7
• open built-in Macro Development IDE
• open Layout with shapes
• activate the MoveQuickly plugin tool
• click a shape
• drag the mouse to get the preview window

I've attached log files.
Analyse von „klayout“.txt
KLayout-Spindump.txt

Reduced call graph (use left/right arrow to scroll):

Call graph:
    2450 Thread_36054941   DispatchQueue_1: com.apple.main-thread  (serial)
    + 2450 start  (in dyld) + 7184  [0x192af9d54]
    +   2450 main  (in klayout) + 336  [0x100e312e8]
    +     2450 klayout_main(int&, char**)  (in klayout) + 1600  [0x100e319d8]
    +                       2450 lay::ApplicationBase::run()  (in libklayout_lay.0.30.7.dylib) + 4260  [0x1041b487c]
    +                         2450 lay::GuiApplication::exec()  (in libklayout_lay.0.30.7.dylib) + 1472  [0x1041b5e70]
    +                           2450 QCoreApplication::exec()  (in QtCore) + 228  [0x10ec53198]
    +                             2450 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>)  (in QtCore) + 588  [0x10ec5c608]
    +                               2450 QCocoaEventDispatcher::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)  (in libqcocoa.dylib) + 2152  [0x113fa54ec]
    +                                                               2450 QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*)  (in QtCore) + 628  [0x10ec53d84]
    +                                                                 2450 lay::GuiApplication::do_notify(QObject*, QEvent*)  (in libklayout_lay.0.30.7.dylib) + 56  [0x1041b55bc]
    +                                                                   2450 QApplication::notify(QObject*, QEvent*)  (in QtWidgets) + 468  [0x10d6117d8]
    +                                                                     2450 QApplicationPrivate::notify_helper(QObject*, QEvent*)  (in QtWidgets) + 336  [0x10d610758]
    +                                                                       2450 QObject::event(QEvent*)  (in QtCore) + 736  [0x10ec9cdb0]
    +                                                                         2450 QPropertyAnimation::~QPropertyAnimation()  (in QtCore) + 40  [0x10edc0530]
    +                                                                           2450 QAbstractAnimation::~QAbstractAnimation()  (in QtCore) + 368  [0x10edb7cb8]
    +                                                                             2450 QObject::~QObject()  (in QtCore) + 1000  [0x10ec9bab4]
    +                                                                               2450 gsi::Callback::issue<QDockWidget_Adaptor, QMetaMethod const&>(void (QDockWidget_Adaptor::*)(QMetaMethod const&), QMetaMethod const&) const  (in libklayout_QtWidgets.0.30.7.dylib) + 220  [0x10fd4a8c0]
    +                                                                                 2450 pya::Callee::call(int, gsi::SerialArgs&, gsi::SerialArgs&) const  (in libklayout_pya.0.30.7.dylib) + 120  [0x102785db0]
    +                                                                                   2450 lay::MacroEditorDialog::start_exec(gsi::Interpreter*)  (in libklayout_lay.0.30.7.dylib) + 376  [0x104217878]
    +                                                                                     2450 void doActivate<false>(QObject*, int, void**)  (in QtCore) + 1480  [0x10eca539c]
    +                                                                                       2450 lay::MacroEditorPage::run_mode_changed()  (in libklayout_lay.0.30.7.dylib) + 108  [0x10422696c]
    +                                                                                         2450 QPlainTextEdit::setReadOnly(bool)  (in QtWidgets) + 60  [0x10d7fc528]
    +                                                                                           2450 QWidgetTextControlPrivate::setCursorVisible(bool)  (in QtWidgets) + 236  [0x10d824650]
    +                                                                                             2450 QObject::disconnectImpl(QObject const*, void**, QObject const*, void**, QMetaObject const*)  (in QtCore) + 348  [0x10eca7718]
    +                                                                                               2450 QMetaObjectPrivate::disconnect(QObject const*, int, QMetaObject const*, QObject const*, int, void**, QMetaObjectPrivate::DisconnectType)  (in QtCore) + 260  [0x10eca154c]
    +                                                                                                 2450 QMetaObjectPrivate::disconnectHelper(QObjectPrivate::ConnectionData*, int, QObject const*, int, void**, QBasicMutex*, QMetaObjectPrivate::DisconnectType)  (in QtCore) + 400  [0x10eca26fc]
    +                                                                                                   2450 QBasicMutex::lockInternal()  (in QtCore) + 188  [0x10edebd6c]
    +                                                                                                     2450 __ulock_wait2  (in libsystem_kernel.dylib) + 8  [0x192e8ec74]

[klayoutmatthias]

My first attempts to reproduce the problem were not successful on Linux with MoveQuicklyToolPlugin 0.21. The UI did not freeze, but I had some internal errors - most likely due to invalid shape references after I left and re-entered the tool. Looks like the selection kind of survives the deactivation of the tool and afterwards it's invalid.

[martinjankoehler]

I could also reproduce it with the IIC-OSIC-TOOLS:latest:

Using

$> gdb -p $(pidof klayout)
thread apply all bt

I get a similar situation

Thread 1 (Thread 0xffffaafb5020 (LWP 3075) "klayout"):
#0  syscall () at ../sysdeps/unix/sysv/linux/aarch64/syscall.S:38
#1  0x0000ffffa2a58428 in QBasicMutex::lockInternal() () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#2  0x0000ffffa2959e18 [PAC] in ??? () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#3  0x0000ffffa296677c [PAC] in QObject::disconnectImpl(QObject const*, void**, QObject const*, void**, QMetaObject const*) () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#4  0x0000ffffa1e64878 [PAC] in ??? () at /lib/aarch64-linux-gnu/libQt6Widgets.so.6
#5  0x0000ffffa1e2e2cc [PAC] in QPlainTextEdit::setReadOnly(bool) () at /lib/aarch64-linux-gnu/libQt6Widgets.so.6
#6  0x0000ffffaabf9cdc [PAC] in ??? () at /foss/tools/klayout/libklayout_lay.so.0
#7  0x0000ffffa296a8e4 in ??? () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#8  0x0000ffffaabd2604 [PAC] in ??? () at /foss/tools/klayout/libklayout_lay.so.0
#9  0x0000ffff9d93bcfc in ??? () at /foss/tools/klayout/libklayout_pya.so.0
#10 0x0000ffffa4788f88 in ??? () at /foss/tools/klayout/libklayout_QtWidgets.so.0
#11 0x0000ffffa295e39c in QObject::~QObject() () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#12 0x0000ffffa2a44e28 [PAC] in QPropertyAnimation::~QPropertyAnimation() () at /lib/aarch64-linux-gnu/libQt6Core.so.6
--Type <RET> for more, q to quit, c to continue without paging--
#13 0x0000ffffa295a52c [PAC] in QObject::event(QEvent*) () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#14 0x0000ffffa1c4026c [PAC] in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib/aarch64-linux-gnu/libQt6Widgets.so.6
#15 0x0000ffffaab7b1d8 [PAC] in lay::GuiApplication::do_notify(QObject*, QEvent*) () at /foss/tools/klayout/libklayout_lay.so.0
#16 0x0000ffffa29146d0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#17 0x0000ffffa291499c [PAC] in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#18 0x0000ffffa2b21700 [PAC] in ??? () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#19 0x0000ffff9ca2f90c [PAC] in ??? () at /lib/aarch64-linux-gnu/libglib-2.0.so.0
#20 0x0000ffff9ca91ae8 [PAC] in ??? () at /lib/aarch64-linux-gnu/libglib-2.0.so.0
#21 0x0000ffff9ca2ebc8 [PAC] in g_main_context_iteration () at /lib/aarch64-linux-gnu/libglib-2.0.so.0
#22 0x0000ffffa2b1ead8 [PAC] in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/aarch64-linux-gnu/libQt6Core.so.6
#23 0x0000ffffa291fdac [PAC] in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/aarch64-linux-gnu/libQt6Core.so.6

[klayoutmatthias]

Problem seems to be a deadlock happening when the disconnectNotify triggers a callback and that enters disconnect itselt

Solution is to put the handler of "run_mode_changed" into the event queue in a delayed fashion.

Thanks for helping debugging :)

Matthias

[klayoutmatthias]

Hi @martinjankoehler,

I implemented the patch, but I wasn't able to reproduce the problem after that, but it also was not easy to reproduce before. I could only see it on Qt6 and only if I managed to hit a certain small time window and switching between macro editor and layout view while dragging with MoveQuicklyPlugin.

Do you have a change to check if the patch fixes the issue for you too?

Thanks,

Matthias

[martinjankoehler]

@klayoutmatthias Looks good! I can't reproduce it either with bugfix/issue-2301