> On Oct. 26, 2015, 5:27 p.m., Aleix Pol Gonzalez wrote:
> > This patch introduced a crash here. Could you maybe look into it? Here's a 
> > backtrace.
> > 
> > It happens on some (not all) programs when the open dialog is displayed. I 
> > can reproduce it with ksnapshot and kdevelop, but not with Kate.
> > 
> > ```
> > (gdb) where
> > #0  0x00007ffff22925f8 in raise () from /usr/lib/libc.so.6
> > #1  0x00007ffff2293a7a in abort () from /usr/lib/libc.so.6
> > #2  0x00007ffff2f3205e in qt_message_fatal (context=..., message=<synthetic 
> > pointer>) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/global/qlogging.cpp:1610
> > #3  QMessageLogger::fatal (this=this@entry=0x7fffffffc070, 
> > msg=msg@entry=0x7ffff31e57f0 "ASSERT: \"%s\" in file %s, line %d") at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/global/qlogging.cpp:784
> > #4  0x00007ffff2f2d5de in qt_assert (assertion=<optimized out>, 
> > file=<optimized out>, line=<optimized out>) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/global/qglobal.cpp:3046
> > #5  0x00007ffff63fb097 in KCoreDirListerCache::slotResult 
> > (this=0x7ffff669b840 <(anonymous 
> > namespace)::Q_QGS_kDirListerCache::innerFunction()::holder>, j=0xe972b0) at 
> > /home/kde-devel/frameworks/kio/src/core/kcoredirlister.cpp:1310
> > #6  0x00007ffff6404e41 in KCoreDirListerCache::qt_static_metacall 
> > (_o=0x7ffff669b840 <(anonymous 
> > namespace)::Q_QGS_kDirListerCache::innerFunction()::holder>, 
> > _c=QMetaObject::InvokeMetaMethod, _id=8, _a=0x7fffffffc390) at 
> > src/core/moc_kcoredirlister_p.cpp:133
> > #7  0x00007ffff314ae6a in QMetaObject::activate (sender=0xe972b0, 
> > signalOffset=<optimized out>, local_signal_index=<optimized out>, 
> > argv=<optimized out>) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/kernel/qobject.cpp:3730
> > #8  0x00007ffff4742f9b in KJob::result (this=0xe972b0, _t1=0xe972b0) at 
> > src/lib/moc_kjob.cpp:555
> > #9  0x00007ffff47419f1 in KJob::emitResult (this=0xe972b0) at 
> > /home/kde-devel/frameworks/kcoreaddons/src/lib/jobs/kjob.cpp:294
> > #10 0x00007ffff47412e4 in KJob::kill (this=0xe972b0, 
> > verbosity=KJob::EmitResult) at 
> > /home/kde-devel/frameworks/kcoreaddons/src/lib/jobs/kjob.cpp:103
> > #11 0x00007ffff63f6473 in KCoreDirListerCache::stopListJob 
> > (this=0x7ffff669b840 <(anonymous 
> > namespace)::Q_QGS_kDirListerCache::innerFunction()::holder>, 
> > url="file:///home/apol/Documents", silent=true) at 
> > /home/kde-devel/frameworks/kio/src/core/kcoredirlister.cpp:493
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #12 0x00007ffff63f6364 in KCoreDirListerCache::stopListingUrl 
> > (this=0x7ffff669b840 <(anonymous 
> > namespace)::Q_QGS_kDirListerCache::innerFunction()::holder>, 
> > lister=0x9ef910, _u=, silent=true) at 
> > /home/kde-devel/frameworks/kio/src/core/kcoredirlister.cpp:463
> > #13 0x00007ffff63f613a in KCoreDirListerCache::stop (this=0x7ffff669b840 
> > <(anonymous namespace)::Q_QGS_kDirListerCache::innerFunction()::holder>, 
> > lister=0x9ef910, silent=true) at 
> > /home/kde-devel/frameworks/kio/src/core/kcoredirlister.cpp:421
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #14 0x00007ffff63f4ea1 in KCoreDirListerCache::listDir (this=0x7ffff669b840 
> > <(anonymous namespace)::Q_QGS_kDirListerCache::innerFunction()::holder>, 
> > lister=0x9ef910, _u=, _keep=false, _reload=false) at 
> > /home/kde-devel/frameworks/kio/src/core/kcoredirlister.cpp:143
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #15 0x00007ffff6400fa0 in KCoreDirLister::openUrl (this=0x9ef910, _url=, 
> > _flags=...) at 
> > /home/kde-devel/frameworks/kio/src/core/kcoredirlister.cpp:2151
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #16 0x00007fffe61e1342 in KDirOperator::Private::openUrl (this=0x9f2ff0, 
> > url=, flags=...) at 
> > /home/kde-devel/frameworks/kio/src/filewidgets/kdiroperator.cpp:1069
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #17 0x00007fffe61e1218 in KDirOperator::setUrl (this=0x9ee560, _newurl=, 
> > clearforward=true) at 
> > /home/kde-devel/frameworks/kio/src/filewidgets/kdiroperator.cpp:1051
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #18 0x00007fffe6204b8c in KFileWidget::setUrl (this=0x89a500, url=, 
> > clearforward=true) at 
> > /home/kde-devel/frameworks/kio/src/filewidgets/kfilewidget.cpp:1460
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #19 0x00007fffe64a82c8 in KDEPlatformFileDialog::setDirectory 
> > (this=0x869a90, directory=) at 
> > /home/kde-devel/frameworks/frameworkintegration/src/platformtheme/kdeplatformfiledialoghelper.cpp:189
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #20 0x00007fffe64a933e in KDEPlatformFileDialogHelper::setDirectory 
> > (this=0x877040, directory=) at 
> > /home/kde-devel/frameworks/frameworkintegration/src/platformtheme/kdeplatformfiledialoghelper.cpp:352
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #21 0x00007ffff3c8978b in QFileDialogPrivate::setDirectory_sys (directory=, 
> > this=<optimized out>) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/dialogs/qfiledialog_p.h:368
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #22 QFileDialog::setDirectoryUrl (this=this@entry=0x7fffffffccb0, 
> > directory=) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/dialogs/qfiledialog.cpp:976
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #23 0x00007ffff3c96988 in QFileDialogPrivate::init (this=0x87caf0, 
> > directory=, 
> >     nameFilter=";;Windows BMP image (*.bmp *.dib);;JPEG-2000 image (*.jp2 
> > *.jpx *.jpf);;JPEG Image (*.jpeg *.jpg *.jpe *.jfif);;PNG image 
> > (*.png);;TIFF image (*.tif *.tiff);;Windows icon (*.ico);;WBMP image 
> > (*.wbmp);;"..., caption="Save Snapshot As")
> >     at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/dialogs/qfiledialog.cpp:2804
> > #24 0x00007ffff3c96e66 in QFileDialog::QFileDialog (this=0x7fffffffccb0, 
> > args=...) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/dialogs/qfiledialog.cpp:373
> > Python Exception <class 'gdb.error'> cannot resolve overloaded method 
> > `data': no arguments supplied: 
> > #25 0x00007ffff3c9789b in QFileDialog::getSaveFileUrl 
> > (parent=0x7fffffffdce0, caption="Save Snapshot As", dir=, 
> >     filter=";;Windows BMP image (*.bmp *.dib);;JPEG-2000 image (*.jp2 *.jpx 
> > *.jpf);;JPEG Image (*.jpeg *.jpg *.jpe *.jfif);;PNG image (*.png);;TIFF 
> > image (*.tif *.tiff);;Windows icon (*.ico);;WBMP image (*.wbmp);;"..., 
> > selectedFilter=0x7fffffffcd90, options=..., 
> >     supportedSchemes=empty QStringList<QString>) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/dialogs/qfiledialog.cpp:2387
> > #26 0x000000000043995d in KSnapshot::slotSaveAs (this=0x7fffffffdce0) at 
> > /home/kde-devel/frameworks/ksnapshot/ksnapshot.cpp:347
> > #27 0x0000000000443ca3 in QtPrivate::FunctorCall<QtPrivate::IndexesList<>, 
> > QtPrivate::List<>, void, void (KSnapshot::*)()>::call(void 
> > (KSnapshot::*)(), KSnapshot*, void**) (f=(void (KSnapshot::*)(KSnapshot * 
> > const)) 0x4396ac <KSnapshot::slotSaveAs()>, o=0x7fffffffdce0, 
> >     arg=0x7fffffffd050) at 
> > /home/kde-devel/kde5/include/QtCore/qobjectdefs_impl.h:501
> > #28 0x0000000000443623 in QtPrivate::FunctionPointer<void 
> > (KSnapshot::*)()>::call<QtPrivate::List<>, void>(void (KSnapshot::*)(), 
> > KSnapshot*, void**) (f=(void (KSnapshot::*)(KSnapshot * const)) 0x4396ac 
> > <KSnapshot::slotSaveAs()>, o=0x7fffffffdce0, arg=0x7fffffffd050)
> >     at /home/kde-devel/kde5/include/QtCore/qobjectdefs_impl.h:520
> > #29 0x0000000000442b03 in QtPrivate::QSlotObject<void (KSnapshot::*)(), 
> > QtPrivate::List<>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, 
> > void**, bool*) (which=1, this_=0x8c4c10, r=0x7fffffffdce0, 
> > a=0x7fffffffd050, ret=0x0)
> >     at /home/kde-devel/kde5/include/QtCore/qobject_impl.h:143
> > #30 0x00007ffff314acf7 in QtPrivate::QSlotObjectBase::call 
> > (a=0x7fffffffd050, r=0x7fffffffdce0, this=<optimized out>) at 
> > ../../include/QtCore/../../../../frameworks/qt5/qtbase/src/corelib/kernel/qobject_impl.h:124
> > #31 QMetaObject::activate (sender=sender@entry=0x8c1fc0, 
> > signalOffset=<optimized out>, 
> > local_signal_index=local_signal_index@entry=2, 
> > argv=argv@entry=0x7fffffffd050) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/kernel/qobject.cpp:3715
> > #32 0x00007ffff314b667 in QMetaObject::activate 
> > (sender=sender@entry=0x8c1fc0, m=m@entry=0x7ffff3f99000 
> > <QAbstractButton::staticMetaObject>, 
> > local_signal_index=local_signal_index@entry=2, 
> > argv=argv@entry=0x7fffffffd050)
> >     at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/kernel/qobject.cpp:3595
> > #33 0x00007ffff3e0f372 in QAbstractButton::clicked 
> > (this=this@entry=0x8c1fc0, _t1=false) at .moc/moc_qabstractbutton.cpp:303
> > #34 0x00007ffff3b8e654 in QAbstractButtonPrivate::emitClicked 
> > (this=0x8c27e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/widgets/qabstractbutton.cpp:533
> > #35 0x00007ffff3b8fb29 in QAbstractButtonPrivate::click (this=0x8c27e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/widgets/qabstractbutton.cpp:526
> > #36 0x00007ffff3b8fc7c in QAbstractButton::mouseReleaseEvent 
> > (this=0x8c1fc0, e=0x7fffffffd4e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/widgets/qabstractbutton.cpp:1131
> > #37 0x00007ffff3af3588 in QWidget::event (this=0x8c1fc0, 
> > event=0x7fffffffd4e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qwidget.cpp:9064
> > #38 0x00007ffff3ab2dcc in QApplicationPrivate::notify_helper 
> > (this=<optimized out>, receiver=0x8c1fc0, e=0x7fffffffd4e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qapplication.cpp:3717
> > #39 0x00007ffff3ab88ce in QApplication::notify (this=<optimized out>, 
> > receiver=0x8c1fc0, e=0x7fffffffd4e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qapplication.cpp:3275
> > #40 0x00007ffff311d2d8 in QCoreApplication::notifyInternal2 
> > (receiver=receiver@entry=0x8c1fc0, event=event@entry=0x7fffffffd4e0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/corelib/kernel/qcoreapplication.cpp:1002
> > #41 0x00007ffff3ab745e in QCoreApplication::sendSpontaneousEvent 
> > (event=0x7fffffffd4e0, receiver=0x8c1fc0) at 
> > ../../include/QtCore/../../../../frameworks/qt5/qtbase/src/corelib/kernel/qcoreapplication.h:230
> > #42 QApplicationPrivate::sendMouseEvent (receiver=receiver@entry=0x8c1fc0, 
> > event=event@entry=0x7fffffffd4e0, alienWidget=alienWidget@entry=0x8c1fc0, 
> > nativeWidget=0x7fffffffdce0, buttonDown=buttonDown@entry=0x7ffff3fa4ba0 
> > <qt_button_down>, lastMouseReceiver=..., 
> >     spontaneous=true) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qapplication.cpp:2770
> > #43 0x00007ffff3b0daa1 in QWidgetWindow::handleMouseEvent 
> > (this=this@entry=0x7be360, event=event@entry=0x7fffffffd8f0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qwidgetwindow.cpp:554
> > #44 0x00007ffff3b0fe7b in QWidgetWindow::event (this=0x7be360, 
> > event=0x7fffffffd8f0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qwidgetwindow.cpp:210
> > #45 0x00007ffff3ab2dcc in QApplicationPrivate::notify_helper 
> > (this=<optimized out>, receiver=0x7be360, e=0x7fffffffd8f0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qapplication.cpp:3717
> > #46 0x00007ffff3ab7d96 in QApplication::notify (this=0x7fffffffde80, 
> > receiver=0x7be360, e=0x7fffffffd8f0) at 
> > /home/kde-devel/frameworks/qt5/qtbase/src/widgets/kernel/qapplication.cpp:3498
> > ```
> 
> Alberto Jiménez Ruiz wrote:
>     Can't reproduce on Kubuntu 15.10.
> 
> Thomas Lübking wrote:
>     Smells like a corrupted stack or threading issue.
>     
>         if (dirData.listersCurrentlyListing.isEmpty()) {
>             qWarning() << "OOOOPS, nothing in 
> directoryData.listersCurrentlyListing for" << jobUrlStr;
>             // We're about to assert; dump the current state...
>     #ifndef NDEBUG
>             printDebug();
>     #endif
>             Q_ASSERT(!dirData.listersCurrentlyListing.isEmpty());
>         }
>         
>     unless printDebug() is capable of polluting 
> dirData.listersCurrentlyListing (it actually looks like that, but you must 
> undefine NDEBUG), either the stack is junk or dirData.listersCurrentlyListing 
> got some elements while we were printing the debug info from some other 
> thread.
>     
>     I'm no way sure what that code is supposed to do but testing
>     if (b)
>        Q_ASSERT(!b);
>     looks insane.
>     
>     In doubt there should be some mutex somewhere or the entire thing doesn't 
> make much sense.
>     
>     It would seem the stricter test to emitResult() causes a later emit and 
> ultimately triggers this.
>     kate will be KF5 - and you need to build debug enabled to be Q_ASSERT != 
> NOOP (so just watch out whether you get the warning)
>     
>     Aleix, if you can reproduce this at will, I suggest to check whether 
> indeed at some point ::printDebug() manipulates 
> dirData.listersCurrentlyListing - eg. add a global reference and test it in 
> each loop in ::printDebug()

if (b) {
       // some debug output
       Q_ASSERT(!b);
    }
is definitely not insane, it's the way to print out more information about the 
problem before aborting.
Much more useful than just Q_ASSERT(!b).
I wager that this is neither a corrupted stack nor a threading issue, but a 
plain old bug.


- David


-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
https://git.reviewboard.kde.org/r/125613/#review87445
-----------------------------------------------------------


On Oct. 24, 2015, 5:54 p.m., Alberto Jiménez Ruiz wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://git.reviewboard.kde.org/r/125613/
> -----------------------------------------------------------
> 
> (Updated Oct. 24, 2015, 5:54 p.m.)
> 
> 
> Review request for kdelibs, Albert Astals Cid and David Faure.
> 
> 
> Bugs: 333436
>     http://bugs.kde.org/show_bug.cgi?id=333436
> 
> 
> Repository: kdelibs
> 
> 
> Description
> -------
> 
> Race condition and error notification loss in ListJob
> 
> 
> Diffs
> -----
> 
>   kio/kio/job.cpp 91712e3 
>   kio/kio/jobclasses.h d771cfe 
>   kio/tests/jobtest.h d3c552e 
>   kio/tests/jobtest.cpp ee2677a 
> 
> Diff: https://git.reviewboard.kde.org/r/125613/diff/
> 
> 
> Testing
> -------
> 
> Update 1, added unittest
> Changed condition of listjob slotresult finishing (When executed as a 
> synchronous job, gets stuck in a eventloop)
> Added setError to copyjob.
> 
> 
> Tests done on Kubuntu 15.10:
> 
> With this folder structure in ~:
> src
> ######c (Folder)
> ##############b (Folder chmod'ed to 700 and owned by root)
> #######################d (10MB file made of /dev/urandom data)
> ##############a (10MB file made of /dev/urandom data)
> 
> Then, (as a normal user execute: "kioclient ~/src ~/dst")
> 
> Expected result: Notification that some files were not able to be copied 
> (Cannot access "b" folder)
> Result with latest kdelibs: Silent copying where b folder is owned by user 
> but nothing inside.
> ---When all kdebugdialog flags are set, a backtrace is also seen.
>       
> subError notifications for listjob subjobs are lost, Copyjob uses this signal 
> to skip data.
> 
> Also, this fix prevents a race condition. 
> 
> ListJob has another ListJob as a subjob.
> 
> Chaild fails for whatever reason and calls error, which calls slotError, 
> which calls slotsFinished and emitResult.
> The result of the child gets collected by parent. slotResult of parent gets 
> called, removes subjob and emitsresult because there are no subjobs left.
> ---That's fine as long as the slave associated with the parent emits finished 
> before the child fails. If it doesn't, parent calls emitsResult twice.
> 
> 
> Result after patch: kioclient shows a MessageBox telling the copy operation 
> could not be completed.
> 
> 
> Thanks,
> 
> Alberto Jiménez Ruiz
> 
>

Reply via email to