User:Frank78ac/SopranoCrash: Difference between revisions

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Most backtraces are incomplete because Soprano debugging info is missing. The best backtraces so far are in {{Bug|235365}} (comment 10); {{Bug|236505}} (Thread 14); {{Bug|237081}} and {{Bug|235083}} (duplicates of {{Bug|234799}}); {{Bug|236868}}, {{Bug|236978}}.
Most backtraces are incomplete because Soprano debugging info is missing. The best backtraces so far are in {{Bug|235365}} (comment 10); {{Bug|236505}} (Thread 14); {{Bug|237081}} and {{Bug|235083}} (duplicates of {{Bug|234799}}); {{Bug|236868}}, {{Bug|236978}}.
=How to reproduce the crash=
A user provided some analysis (see {{Bug|234799}} comments 22, 27,29): To reproduce the bug, Nepomuk must be enabled in the System Settings, and Dolphin's tool tips must be enabled.
A way to reproduce this is:
# Disable Nepomuk
# Start Dolphin, select a folder with many pictures
# Configure Nepomuk/Strigi to index only the picture folder and start Nepomuk
# Switch to Dolphin, hover the pictures with the mouse
It may help to hover several pictures and to switch between different subfolders of the pictures folder (all containing pictures themselves) between hovering.
=Typical Backtrace=
The backtrace indicates a problem with simultaneous malloc/free calls from different threads.
Application: Dolphin (dolphin), signal: Aborted
[Current thread is 1 (Thread 0x7fb34bdec760 (LWP 2977))]
Thread 3 (Thread 0x7fb33b3f3710 (LWP 2982)):
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
#1  0x00007fb347a043ac in _L_lock_12430 () from /lib/libc.so.6
#2  0x00007fb347a02e48 in *__GI___libc_free (mem=0x7fb347d02e40) at malloc.c:3736
#3  0x00007fb3481b2981 in socketNotifierSourceCheck (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:92
#4  0x00007fb343e84b0a in IA__g_main_context_check (context=0xcdd200, max_priority=2147483647, fds=<value optimized out>, n_fds=-1) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2469
#5  0x00007fb343e854c3 in g_main_context_iterate (context=0xcdd200, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>)
    at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2588
#6  0x00007fb343e858fc in IA__g_main_context_iteration (context=0xcdd200, may_block=1) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2654
#7  0x00007fb3481b2513 in QEventDispatcherGlib::processEvents (this=0xadf0e0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#8  0x00007fb348187992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#9  0x00007fb348187d6c in QEventLoop::exec (this=0x7fb33b3f2db0, flags=) at kernel/qeventloop.cpp:201
#10 0x00007fb348091d59 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:487
#11 0x00007fb348168178 in QInotifyFileSystemWatcherEngine::run (this=0xcdb550) at io/qfilesystemwatcher_inotify.cpp:248
#12 0x00007fb348094775 in QThreadPrivate::start (arg=0xcdb550) at thread/qthread_unix.cpp:248
#13 0x00007fb344fca9ca in start_thread (arg=<value optimized out>) at pthread_create.c:300
#14 0x00007fb347a6b69d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#15 0x0000000000000000 in ?? ()
Thread 2 (Thread 0x7fb333fff710 (LWP 3019)):
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
#1  0x00007fb347a043ac in _L_lock_12430 () from /lib/libc.so.6
#2  0x00007fb347a02e48 in *__GI___libc_free (mem=0x7fb347d02e40) at malloc.c:3736
#3  0x00007fb34a83c3e1 in ~Private (this=0x7fb333ffe040, __in_chrg=<value optimized out>) at ../../soprano/error.cpp:187
#4  ~ErrorCache (this=0x7fb333ffe040, __in_chrg=<value optimized out>) at ../../soprano/error.cpp:202
#5  0x00007fb345e06bf8 in Soprano::Client::ClientConnection::iteratorClose (this=0xeaf310, id=1537984332) at ../../client/clientconnection.cpp:718
#6  0x00007fb345e085f5 in Soprano::Client::ClientModel::closeIterator (this=0xc109c0, id=1537984332) at ../../client/clientmodel.cpp:234
#7  0x00007fb345e09bfa in Soprano::Client::ClientQueryResultIteratorBackend::close (this=0xdde320) at ../../client/clientqueryresultiteratorbackend.cpp:74
#8  0x00007fb34ab130e4 in Soprano::Iterator<Soprano::BindingSet>::close (this=0x7fb333ffe290) at /usr/include/Soprano/../soprano/iterator.h:229
#9  0x00007fb34ab0f6db in Nepomuk::ResourceData::determineUri (this=0xe63320) at ../../../nepomuk/core/resourcedata.cpp:681
#10 0x00007fb34ab10802 in Nepomuk::ResourceData::load (this=0xe63320) at ../../../nepomuk/core/resourcedata.cpp:414
#11 0x00007fb34ab111b8 in Nepomuk::ResourceData::property (this=0xe63320, uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#12 0x00007fb34ab2bee2 in Nepomuk::Resource::property (this=<value optimized out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#13 0x00007fb34ab2e9d0 in Nepomuk::Resource::rating (this=0x7fb333ffec80) at ../../../nepomuk/core/resource.cpp:800
#14 0x00007fb34b296640 in KLoadMetaDataThread::run (this=0xf478a0) at ../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95
#15 0x00007fb348094775 in QThreadPrivate::start (arg=0xf478a0) at thread/qthread_unix.cpp:248
#16 0x00007fb344fca9ca in start_thread (arg=<value optimized out>) at pthread_create.c:300
#17 0x00007fb347a6b69d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#18 0x0000000000000000 in ?? ()
Thread 1 (Thread 0x7fb34bdec760 (LWP 2977)):
[KCrash Handler]
#5  0x00007fb3479b8a75 in *__GI_raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#6  0x00007fb3479bc5c0 in *__GI_abort () at abort.c:92
#7  0x00007fb3479f24fb in __libc_message (do_abort=<value optimized out>, fmt=<value optimized out>) at ../sysdeps/unix/sysv/linux/libc_fatal.c:189
#8  0x00007fb3479fc5b6 in malloc_printerr (action=3, str=0x7fb347ace7f8 "malloc(): smallbin double linked list corrupted", ptr=<value optimized out>) at malloc.c:6264
#9  0x00007fb347a008e9 in _int_malloc (av=0x7fb347d02e40, bytes=16) at malloc.c:4306
#10 0x00007fb347a0158e in *__GI___libc_malloc (bytes=16) at malloc.c:3660
#11 0x00007fb3428ea038 in ?? () from /usr/lib/libxcb.so.1
#12 0x00007fb3428e832d in ?? () from /usr/lib/libxcb.so.1
#13 0x00007fb3428e9c2c in xcb_wait_for_reply () from /usr/lib/libxcb.so.1
#14 0x00007fb3469948d3 in _XReply () from /usr/lib/libX11.so.6
#15 0x00007fb346971697 in XGetWindowProperty () from /usr/lib/libX11.so.6
#16 0x00007fb34697079c in XGetWMHints () from /usr/lib/libX11.so.6
#17 0x00007fb348e14ddc in QWidgetPrivate::setWindowIcon_sys (this=<value optimized out>, forceReset=<value optimized out>) at kernel/qwidget_x11.cpp:1512
#18 0x00007fb348dcd858 in QWidget::create (this=0xf1c030, window=0, initializeWindow=<value optimized out>, destroyOldWindow=<value optimized out>) at kernel/qwidget.cpp:1351
#19 0x00007fb348dd36d6 in QWidget::setVisible (this=0xf1c030, visible=<value optimized out>) at kernel/qwidget.cpp:7353
#20 0x00007fb34b28d1c8 in ToolTipManager::showToolTip (this=0xaa7b30, pixmap=<value optimized out>) at ../../../../apps/dolphin/src/tooltips/tooltipmanager.cpp:241
#21 0x00007fb34b28d4b3 in ToolTipManager::prepareToolTip (this=0xaa7b30) at ../../../../apps/dolphin/src/tooltips/tooltipmanager.cpp:158
#22 0x00007fb34b28d744 in ToolTipManager::qt_metacall (this=0xaa7b30, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff171b6490) at ./tooltipmanager.moc:85
#23 0x00007fb34819be3f in QMetaObject::activate (sender=0xaa78d0, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0xffffffffffffffff) at kernel/qobject.cpp:3293
#24 0x00007fb348198a63 in QObject::event (this=0xaa78d0, e=0x7fff171b6be0) at kernel/qobject.cpp:1212
#25 0x00007fb348d7622c in QApplicationPrivate::notify_helper (this=0x7d0dd0, receiver=0xaa78d0, e=0x7fff171b6be0) at kernel/qapplication.cpp:4300
#26 0x00007fb348d7c6fb in QApplication::notify (this=0x7fff171b6f30, receiver=0xaa78d0, e=0x7fff171b6be0) at kernel/qapplication.cpp:4183
#27 0x00007fb349a81526 in KApplication::notify (this=0x7fff171b6f30, receiver=0xaa78d0, event=0x7fff171b6be0) at ../../kdeui/kernel/kapplication.cpp:302
#28 0x00007fb34818906c in QCoreApplication::notifyInternal (this=0x7fff171b6f30, receiver=0xaa78d0, event=0x7fff171b6be0) at kernel/qcoreapplication.cpp:704
#29 0x00007fb3481b5d42 in QCoreApplication::sendEvent (this=0x7d65e0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#30 QTimerInfoList::activateTimers (this=0x7d65e0) at kernel/qeventdispatcher_unix.cpp:603
#31 0x00007fb3481b2848 in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#32 idleTimerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:231
#33 0x00007fb343e818c2 in g_main_dispatch (context=0x7d5520) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:1960
#34 IA__g_main_context_dispatch (context=0x7d5520) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2513
#35 0x00007fb343e85748 in g_main_context_iterate (context=0x7d5520, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>)
    at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2591
#36 0x00007fb343e858fc in IA__g_main_context_iteration (context=0x7d5520, may_block=1) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2654
#37 0x00007fb3481b2513 in QEventDispatcherGlib::processEvents (this=0x7a9770, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#38 0x00007fb348e2646e in QGuiEventDispatcherGlib::processEvents (this=0xba1, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#39 0x00007fb348187992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#40 0x00007fb348187d6c in QEventLoop::exec (this=0x7fff171b6e80, flags=) at kernel/qeventloop.cpp:201
#41 0x00007fb34818baab in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#42 0x000000000043b1c5 in main (argc=<value optimized out>, argv=<value optimized out>) at ../../../../apps/dolphin/src/main.cpp:101


= Master bugs =
= Master bugs =

Revision as of 15:04, 16 May 2010

There were lots of reports about Soprano/Nepomuk-related crashes recently. Most of them are for Kubuntu 10.04, but there are also some from users of other distributions like bug #236082 (Debian) and bug #236505 (Opensuse)

Most backtraces are incomplete because Soprano debugging info is missing. The best backtraces so far are in bug #235365 (comment 10); bug #236505 (Thread 14); bug #237081 and bug #235083 (duplicates of bug #234799); bug #236868, bug #236978.

How to reproduce the crash

A user provided some analysis (see bug #234799 comments 22, 27,29): To reproduce the bug, Nepomuk must be enabled in the System Settings, and Dolphin's tool tips must be enabled.

A way to reproduce this is:

  1. Disable Nepomuk
  2. Start Dolphin, select a folder with many pictures
  3. Configure Nepomuk/Strigi to index only the picture folder and start Nepomuk
  4. Switch to Dolphin, hover the pictures with the mouse

It may help to hover several pictures and to switch between different subfolders of the pictures folder (all containing pictures themselves) between hovering.

Typical Backtrace

The backtrace indicates a problem with simultaneous malloc/free calls from different threads.

Application: Dolphin (dolphin), signal: Aborted
[Current thread is 1 (Thread 0x7fb34bdec760 (LWP 2977))]
Thread 3 (Thread 0x7fb33b3f3710 (LWP 2982)):
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
#1  0x00007fb347a043ac in _L_lock_12430 () from /lib/libc.so.6
#2  0x00007fb347a02e48 in *__GI___libc_free (mem=0x7fb347d02e40) at malloc.c:3736
#3  0x00007fb3481b2981 in socketNotifierSourceCheck (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:92
#4  0x00007fb343e84b0a in IA__g_main_context_check (context=0xcdd200, max_priority=2147483647, fds=<value optimized out>, n_fds=-1) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2469
#5  0x00007fb343e854c3 in g_main_context_iterate (context=0xcdd200, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>)
   at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2588
#6  0x00007fb343e858fc in IA__g_main_context_iteration (context=0xcdd200, may_block=1) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2654
#7  0x00007fb3481b2513 in QEventDispatcherGlib::processEvents (this=0xadf0e0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#8  0x00007fb348187992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#9  0x00007fb348187d6c in QEventLoop::exec (this=0x7fb33b3f2db0, flags=) at kernel/qeventloop.cpp:201
#10 0x00007fb348091d59 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:487
#11 0x00007fb348168178 in QInotifyFileSystemWatcherEngine::run (this=0xcdb550) at io/qfilesystemwatcher_inotify.cpp:248
#12 0x00007fb348094775 in QThreadPrivate::start (arg=0xcdb550) at thread/qthread_unix.cpp:248
#13 0x00007fb344fca9ca in start_thread (arg=<value optimized out>) at pthread_create.c:300
#14 0x00007fb347a6b69d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#15 0x0000000000000000 in ?? ()
Thread 2 (Thread 0x7fb333fff710 (LWP 3019)):
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
#1  0x00007fb347a043ac in _L_lock_12430 () from /lib/libc.so.6
#2  0x00007fb347a02e48 in *__GI___libc_free (mem=0x7fb347d02e40) at malloc.c:3736
#3  0x00007fb34a83c3e1 in ~Private (this=0x7fb333ffe040, __in_chrg=<value optimized out>) at ../../soprano/error.cpp:187
#4  ~ErrorCache (this=0x7fb333ffe040, __in_chrg=<value optimized out>) at ../../soprano/error.cpp:202
#5  0x00007fb345e06bf8 in Soprano::Client::ClientConnection::iteratorClose (this=0xeaf310, id=1537984332) at ../../client/clientconnection.cpp:718
#6  0x00007fb345e085f5 in Soprano::Client::ClientModel::closeIterator (this=0xc109c0, id=1537984332) at ../../client/clientmodel.cpp:234
#7  0x00007fb345e09bfa in Soprano::Client::ClientQueryResultIteratorBackend::close (this=0xdde320) at ../../client/clientqueryresultiteratorbackend.cpp:74
#8  0x00007fb34ab130e4 in Soprano::Iterator<Soprano::BindingSet>::close (this=0x7fb333ffe290) at /usr/include/Soprano/../soprano/iterator.h:229
#9  0x00007fb34ab0f6db in Nepomuk::ResourceData::determineUri (this=0xe63320) at ../../../nepomuk/core/resourcedata.cpp:681
#10 0x00007fb34ab10802 in Nepomuk::ResourceData::load (this=0xe63320) at ../../../nepomuk/core/resourcedata.cpp:414
#11 0x00007fb34ab111b8 in Nepomuk::ResourceData::property (this=0xe63320, uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#12 0x00007fb34ab2bee2 in Nepomuk::Resource::property (this=<value optimized out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#13 0x00007fb34ab2e9d0 in Nepomuk::Resource::rating (this=0x7fb333ffec80) at ../../../nepomuk/core/resource.cpp:800
#14 0x00007fb34b296640 in KLoadMetaDataThread::run (this=0xf478a0) at ../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95
#15 0x00007fb348094775 in QThreadPrivate::start (arg=0xf478a0) at thread/qthread_unix.cpp:248
#16 0x00007fb344fca9ca in start_thread (arg=<value optimized out>) at pthread_create.c:300
#17 0x00007fb347a6b69d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#18 0x0000000000000000 in ?? ()
Thread 1 (Thread 0x7fb34bdec760 (LWP 2977)):
[KCrash Handler]
#5  0x00007fb3479b8a75 in *__GI_raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#6  0x00007fb3479bc5c0 in *__GI_abort () at abort.c:92
#7  0x00007fb3479f24fb in __libc_message (do_abort=<value optimized out>, fmt=<value optimized out>) at ../sysdeps/unix/sysv/linux/libc_fatal.c:189
#8  0x00007fb3479fc5b6 in malloc_printerr (action=3, str=0x7fb347ace7f8 "malloc(): smallbin double linked list corrupted", ptr=<value optimized out>) at malloc.c:6264
#9  0x00007fb347a008e9 in _int_malloc (av=0x7fb347d02e40, bytes=16) at malloc.c:4306
#10 0x00007fb347a0158e in *__GI___libc_malloc (bytes=16) at malloc.c:3660
#11 0x00007fb3428ea038 in ?? () from /usr/lib/libxcb.so.1
#12 0x00007fb3428e832d in ?? () from /usr/lib/libxcb.so.1
#13 0x00007fb3428e9c2c in xcb_wait_for_reply () from /usr/lib/libxcb.so.1
#14 0x00007fb3469948d3 in _XReply () from /usr/lib/libX11.so.6
#15 0x00007fb346971697 in XGetWindowProperty () from /usr/lib/libX11.so.6
#16 0x00007fb34697079c in XGetWMHints () from /usr/lib/libX11.so.6
#17 0x00007fb348e14ddc in QWidgetPrivate::setWindowIcon_sys (this=<value optimized out>, forceReset=<value optimized out>) at kernel/qwidget_x11.cpp:1512
#18 0x00007fb348dcd858 in QWidget::create (this=0xf1c030, window=0, initializeWindow=<value optimized out>, destroyOldWindow=<value optimized out>) at kernel/qwidget.cpp:1351
#19 0x00007fb348dd36d6 in QWidget::setVisible (this=0xf1c030, visible=<value optimized out>) at kernel/qwidget.cpp:7353
#20 0x00007fb34b28d1c8 in ToolTipManager::showToolTip (this=0xaa7b30, pixmap=<value optimized out>) at ../../../../apps/dolphin/src/tooltips/tooltipmanager.cpp:241
#21 0x00007fb34b28d4b3 in ToolTipManager::prepareToolTip (this=0xaa7b30) at ../../../../apps/dolphin/src/tooltips/tooltipmanager.cpp:158
#22 0x00007fb34b28d744 in ToolTipManager::qt_metacall (this=0xaa7b30, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff171b6490) at ./tooltipmanager.moc:85
#23 0x00007fb34819be3f in QMetaObject::activate (sender=0xaa78d0, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0xffffffffffffffff) at kernel/qobject.cpp:3293
#24 0x00007fb348198a63 in QObject::event (this=0xaa78d0, e=0x7fff171b6be0) at kernel/qobject.cpp:1212
#25 0x00007fb348d7622c in QApplicationPrivate::notify_helper (this=0x7d0dd0, receiver=0xaa78d0, e=0x7fff171b6be0) at kernel/qapplication.cpp:4300
#26 0x00007fb348d7c6fb in QApplication::notify (this=0x7fff171b6f30, receiver=0xaa78d0, e=0x7fff171b6be0) at kernel/qapplication.cpp:4183
#27 0x00007fb349a81526 in KApplication::notify (this=0x7fff171b6f30, receiver=0xaa78d0, event=0x7fff171b6be0) at ../../kdeui/kernel/kapplication.cpp:302
#28 0x00007fb34818906c in QCoreApplication::notifyInternal (this=0x7fff171b6f30, receiver=0xaa78d0, event=0x7fff171b6be0) at kernel/qcoreapplication.cpp:704
#29 0x00007fb3481b5d42 in QCoreApplication::sendEvent (this=0x7d65e0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#30 QTimerInfoList::activateTimers (this=0x7d65e0) at kernel/qeventdispatcher_unix.cpp:603
#31 0x00007fb3481b2848 in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#32 idleTimerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:231
#33 0x00007fb343e818c2 in g_main_dispatch (context=0x7d5520) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:1960
#34 IA__g_main_context_dispatch (context=0x7d5520) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2513
#35 0x00007fb343e85748 in g_main_context_iterate (context=0x7d5520, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>)
   at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2591
#36 0x00007fb343e858fc in IA__g_main_context_iteration (context=0x7d5520, may_block=1) at /build/buildd/glib2.0-2.24.0/glib/gmain.c:2654
#37 0x00007fb3481b2513 in QEventDispatcherGlib::processEvents (this=0x7a9770, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#38 0x00007fb348e2646e in QGuiEventDispatcherGlib::processEvents (this=0xba1, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#39 0x00007fb348187992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#40 0x00007fb348187d6c in QEventLoop::exec (this=0x7fff171b6e80, flags=) at kernel/qeventloop.cpp:201
#41 0x00007fb34818baab in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#42 0x000000000043b1c5 in main (argc=<value optimized out>, argv=<value optimized out>) at ../../../../apps/dolphin/src/main.cpp:101

Master bugs

I've tried to collect reports with the same backtraces into several master bugs.

bug #236868 Failed malloc in QByteArray/qt_error_string/report_error/QMutexPrivate::wait/QMutex::lock

#5  malloc_consolidate (av=0x7fede0000020) at malloc.c:5134
#6  0x00007fee03cd4fad in _int_malloc (av=0x7fede0000020, bytes=1056) at
malloc.c:4370
#7  0x00007fee03cd658e in *__GI___libc_malloc (bytes=1056) at malloc.c:3660
#8  0x00007fee0436bdd1 in QByteArray (this=0x7fede4a32f30, size=1024, ch=0
'\000') at tools/qbytearray.cpp:1313
#9  0x00007fee04361e7f in qt_error_string (errorCode=22) at
global/qglobal.cpp:2125
#10 0x00007fee04368c17 in report_error (code=<value optimized out>,
where=0x7fee044c053b "QMutex::lock", what=0x7fee044c050a "mutex lock") at
thread/qmutex_unix.cpp:61
#11 0x00007fee04368d6d in QMutexPrivate::wait (this=0x7fede0036890, timeout=-1)
at thread/qmutex_unix.cpp:80
#12 0x00007fee043649e5 in QMutex::lock (this=0x7fede00e86b8) at
thread/qmutex.cpp:167
#13 0x00007fee06b12095 in QMutexLocker::relock (this=0x7fede01c7fc0) at
/usr/include/qt4/QtCore/qmutex.h:120
#14 QMutexLocker (this=0x7fede01c7fc0) at /usr/include/qt4/QtCore/qmutex.h:102
#15 Soprano::Error::ErrorCache::clearError (this=0x7fede01c7fc0) at
../../soprano/error.cpp:242
#16 0x00007fee020dd598 in Soprano::Client::ClientModel::closeIterator
(this=0x7fede01c7fb0, id=70428338) at ../../client/clientmodel.cpp:231
#17 0x00007fee020debfa in
Soprano::Client::ClientQueryResultIteratorBackend::close (this=0x7fede02257a0)
at ../../client/clientqueryresultiteratorbackend.cpp:74
#18 0x00007fee06b00fa6 in ~Private (this=0x7fede4a332c0, __in_chrg=<value
optimized out>) at ../../soprano/iterator.h:172
#19 ~QSharedDataPointer (this=0x7fede4a332c0, __in_chrg=<value optimized out>)
at /usr/include/qt4/QtCore/qshareddata.h:90
#20 ~Iterator (this=0x7fede4a332c0, __in_chrg=<value optimized out>) at
../../soprano/iterator.h:202
#21 0x00007fee06de46eb in Nepomuk::ResourceData::determineUri
(this=0x7fede02239a0) at ../../../nepomuk/core/resourcedata.cpp:712
#22 0x00007fee06de5802 in Nepomuk::ResourceData::load (this=0x7fede02239a0) at
../../../nepomuk/core/resourcedata.cpp:414
#23 0x00007fee06de61b8 in Nepomuk::ResourceData::property (this=0x7fede02239a0,
uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#24 0x00007fee06e00ee2 in Nepomuk::Resource::property (this=<value optimized
out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#25 0x00007fee06e01039 in Nepomuk::Resource::tags (this=0x7fede4a33c80) at
../../../nepomuk/core/resource.cpp:633
#26 0x0000000000465cd8 in KLoadMetaDataThread::run (this=0x4491990) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:104

Note that another thread calls free() when the malloc() call fails. There are more bug reports where crashes occur while two different threads try to do memory operations, e.g., bug #236624, bug #235210, bug #235938, bug #235974, bug #214769

Note: There are also crashes of this kind (malloc/free in two threads) which do not involve Nepomuk/Soprano, e.g., bug #236499

bug #235166 QMutex::lock

#5  0x00007fa3f88108dc in QMutex::lock (this=0x9d44d0) at thread/qmutex.cpp:150
#6  0x00007fa3f6589add in ?? () from /usr/lib/libsopranoclient.so.1
#7  0x00007fa3fb29bb9d in Nepomuk::MainModel::executeQuery (this=0xbdd120,
query=..., language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...)
   at ../../../nepomuk/core/nepomukmainmodel.cpp:213
#8  0x00007fa3fafcd77c in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#9  0x00007fa3fb291fa2 in Nepomuk::ResourceData::load (this=0xc3fc70) at
../../../nepomuk/core/resourcedata.cpp:447
#10 0x00007fa3fb2921b8 in Nepomuk::ResourceData::property (this=0xc3fc70,
uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#11 0x00007fa3fb2acee2 in Nepomuk::Resource::property (this=<value optimized
out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#12 0x00007fa3fb2af9d0 in Nepomuk::Resource::rating (this=0x7fa3ebb29c80) at
../../../nepomuk/core/resource.cpp:800
#13 0x0000000000465b08 in KLoadMetaDataThread::run (this=0xc142f0) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

A similar backtrace from bug #236978:

#6  QBasicAtomicInt::deref (this=0xb0c08b80) at
../../include/QtCore/../../src/corelib/arch/qatomic_i386.h:132
#7  QMutex::lock (this=0xb0c08b80) at thread/qmutex.cpp:172
#8  0x006c5000 in QMutexLocker::relock (this=0xb0c08b60, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
/usr/include/qt4/QtCore/qmutex.h:120
#9  QMutexLocker (this=0xb0c08b60, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
/usr/include/qt4/QtCore/qmutex.h:102
#10 Soprano::Client::ClientModel::executeQuery (this=0xb0c08b60, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
../../client/clientmodel.cpp:103
#11 0x00ac1a30 in Nepomuk::MainModel::executeQuery (this=0x8b04b00, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
../../../nepomuk/core/nepomukmainmodel.cpp:213
#12 0x001e43cd in Soprano::FilterModel::executeQuery (this=0x881f138,
query=..., language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...)
at ../../soprano/filtermodel.cpp:164
#13 0x00ab5335 in Nepomuk::ResourceData::determineUri (this=0xa076b20) at
../../../nepomuk/core/resourcedata.cpp:671
#14 0x00ab66a0 in Nepomuk::ResourceData::load (this=0xa076b20) at
../../../nepomuk/core/resourcedata.cpp:414
#15 0x00ab719b in Nepomuk::ResourceData::property (this=0xa076b20, uri=...) at
../../../nepomuk/core/resourcedata.cpp:271
#16 0x00ad4cb7 in Nepomuk::Resource::property (this=0xae0cc294, uri=...) at
../../../nepomuk/core/resource.cpp:280
#17 0x00ad7d41 in Nepomuk::Resource::rating (this=0xae0cc294) at
../../../nepomuk/core/resource.cpp:800
#18 0x080aa1e9 in KLoadMetaDataThread::run (this=0x9c7c970) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

bug #234799 Soprano::Iterator<Soprano::BindingSet>::next

Backtrace from bug #237081:
Thread 2 (Thread 0xb306fb70 (LWP 2855)):
[KCrash Handler]
#6  0x0066c6d4 in QPointer<Soprano::Client::ClientConnection>::operator
Soprano::Client::ClientConnection* (this=0xb3b23c8) at
/usr/include/qt4/QtCore/qpointer.h:78
#7  Soprano::Client::ClientModel::client (this=0xb3b23c8) at
../../client/clientmodel.h:57
#8  Soprano::Client::ClientQueryResultIteratorBackend::next (this=0xb3b23c8) at
../../client/clientqueryresultiteratorbackend.cpp:47
#9  0x00d731cf in Soprano::Iterator<Soprano::BindingSet>::next
(this=0xb306f028) at /usr/include/Soprano/../soprano/iterator.h:239
#10 0x00d6f83e in Nepomuk::ResourceData::load (this=0xb3b0d78) at
../../../nepomuk/core/resourcedata.cpp:419
#11 0x00d7019b in Nepomuk::ResourceData::property (this=0xb3b0d78, uri=...) at
../../../nepomuk/core/resourcedata.cpp:271
#12 0x00d8dcb7 in Nepomuk::Resource::property (this=0xb306f294, uri=...) at
../../../nepomuk/core/resource.cpp:280
#13 0x00d90d41 in Nepomuk::Resource::rating (this=0xb306f294) at
../../../nepomuk/core/resource.cpp:800
#14 0x080aa1e9 in KLoadMetaDataThread::run (this=0xa1f24b8) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95
[...]
Most duplicates have this incomplete backtrace:
#5  0x00007fc44be9af25 in ?? () from /usr/lib/libsopranoclient.so.1
#6  0x00007fc450ba4d0e in Soprano::Iterator<Soprano::BindingSet>::next
(this=0x7fc4393467b0) at /usr/include/Soprano/../soprano/iterator.h:239
#7  0x00007fc450ba19f0 in Nepomuk::ResourceData::load (this=<value optimized
out>) at ../../../nepomuk/core/resourcedata.cpp:419
#8  0x00007fc450ba21b8 in Nepomuk::ResourceData::property (this=0x18d8090,
uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#9  0x00007fc450bbcee2 in Nepomuk::Resource::property (this=<value optimized
out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#10 0x00007fc450bbf9d0 in Nepomuk::Resource::rating (this=0x7fc439346c80) at
../../../nepomuk/core/resource.cpp:800
#11 0x0000000000465b08 in KLoadMetaDataThread::run (this=0x1841550) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

bug #232698 QBasicAtomicInt::operator!=

#7  0x02ab8a34 in QBasicAtomicInt::operator!=(int) const () from
/home/hunny/kde/lib/libsopranoclient.so.1
#8  0x02ac0bf3 in QList<int>::detach() () from
/home/hunny/kde/lib/libsopranoclient.so.1
#9  0x02ac09cd in QList<int>::append(int const&) () from
/home/hunny/kde/lib/libsopranoclient.so.1
#10 0x02abfaa8 in Soprano::Client::ClientModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/home/hunny/kde/lib/libsopranoclient.so.1
#11 0x02cf92a4 in Nepomuk::MainModel::executeQuery (this=0x9124c80, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...)
    at /home/hunny/kde/src/KDE/kdelibs/nepomuk/core/nepomukmainmodel.cpp:213
#12 0x02d977c9 in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/home/hunny/kde/lib/libsoprano.so.4
#13 0x02ceec5e in Nepomuk::ResourceData::determineUri (this=0x9495f20) at
/home/hunny/kde/src/KDE/kdelibs/nepomuk/core/resourcedata.cpp:671
#14 0x02ced714 in Nepomuk::ResourceData::load (this=0x9495f20) at
/home/hunny/kde/src/KDE/kdelibs/nepomuk/core/resourcedata.cpp:414
#15 0x02cec8f7 in Nepomuk::ResourceData::property (this=0x9495f20, uri=...) at
/home/hunny/kde/src/KDE/kdelibs/nepomuk/core/resourcedata.cpp:271
#16 0x02d0a87d in Nepomuk::Resource::property (this=0xb5503218, uri=...) at
/home/hunny/kde/src/KDE/kdelibs/nepomuk/core/resource.cpp:282
#17 0x02d0b9eb in Nepomuk::Resource::description (this=0xb5503218) at
/home/hunny/kde/src/KDE/kdelibs/nepomuk/core/resource.cpp:525
#18 0x02b9fa68 in KLoadFileMetaDataThread::run (this=0x93fe698) at
/home/hunny/kde/src/KDE/kdelibs/kfile/kloadfilemetadatathread.cpp:100

bug #234690 QMutex::lock, QCoreApplication::postEvent

#6  QMutex::lock (this=0xd00ab859) at thread/qmutex.cpp:150
#7  0x01230634 in QCoreApplication::postEvent (receiver=0xb19af48,
event=0xa049a90, priority=0) at kernel/qcoreapplication.cpp:1113
#8  0x012309ac in QCoreApplication::postEvent (receiver=0xb19af48,
event=0xa049a90) at kernel/qcoreapplication.cpp:1066
#9  0x01242236 in queued_activate (sender=<value optimized out>, signal=<value
optimized out>, c=0x9bb7680, argv=0xb3fb7a2c, semaphore=0x0) at
kernel/qobject.cpp:3173
#10 0x012442b1 in QMetaObject::activate (sender=0x8fdaa58, m=0x1343c48,
local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3266
#11 0x01293797 in QIODevice::readyRead (this=0x8fdaa58) at
.moc/release-shared/moc_qiodevice.cpp:91
#12 0x013e8df2 in QAbstractSocketPrivate::canReadNotification (this=0xc814538)
at socket/qabstractsocket.cpp:626
#13 0x013e943e in QAbstractSocket::waitForReadyRead (this=0x8fdaa58,
msecs=600000) at socket/qabstractsocket.cpp:1822
#14 0x013f3f12 in QLocalSocket::waitForReadyRead (this=0xb19af48, msecs=600000)
at socket/qlocalsocket_unix.cpp:576
#15 0x00a4d0da in ?? () from /usr/lib/libsopranoclient.so.1
#16 0x00a49a25 in Soprano::Client::LocalSocketClient::connect(QString const&)
() from /usr/lib/libsopranoclient.so.1
#17 0x003028ce in init (this=0x82e4a20, forced=<value optimized out>) at
../../../nepomuk/core/nepomukmainmodel.cpp:101
#18 0x003039d4 in model (this=0x813b700, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
../../../nepomuk/core/nepomukmainmodel.cpp:112
#19 Nepomuk::MainModel::executeQuery (this=0x813b700, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
../../../nepomuk/core/nepomukmainmodel.cpp:213
#20 0x005383cd in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#21 0x002f7335 in Nepomuk::ResourceData::determineUri (this=0xb57135d8) at
../../../nepomuk/core/resourcedata.cpp:671
#22 0x002f86a0 in Nepomuk::ResourceData::load (this=0xb57135d8) at
../../../nepomuk/core/resourcedata.cpp:414
#23 0x002f919b in Nepomuk::ResourceData::property (this=0xb57135d8, uri=...) at
../../../nepomuk/core/resourcedata.cpp:271
#24 0x00316cb7 in Nepomuk::Resource::property (this=0xb3fb8294, uri=...) at
../../../nepomuk/core/resource.cpp:280
#25 0x00319d41 in Nepomuk::Resource::rating (this=0xb3fb8294) at
../../../nepomuk/core/resource.cpp:800
#26 0x080aa1e9 in KLoadMetaDataThread::run (this=0xa6a26f8) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

bug #234994 Soprano::Error::ErrorCache::clearError

#5  0x00007ff2b4efd0a2 in Soprano::Error::ErrorCache::clearError() const ()
from /usr/lib/libsoprano.so.4
#6  0x00007ff2b4efd740 in
Soprano::Error::ErrorCache::setError(Soprano::Error::Error const&) const ()
from /usr/lib/libsoprano.so.4
#7  0x00007ff2b04c8a5a in ?? () from /usr/lib/libsopranoclient.so.1
#8  0x00007ff2b51dab9d in Nepomuk::MainModel::executeQuery (this=0x279a4e0,
query=..., language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...)
    at ../../../nepomuk/core/nepomukmainmodel.cpp:213
#9  0x00007ff2b4f0c77c in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#10 0x00007ff2b51cf635 in Nepomuk::ResourceData::determineUri (this=0x2f8fb60)
at ../../../nepomuk/core/resourcedata.cpp:671
#11 0x00007ff2b51d0802 in Nepomuk::ResourceData::load (this=0x2f8fb60) at
../../../nepomuk/core/resourcedata.cpp:414
#12 0x00007ff2b51d11b8 in Nepomuk::ResourceData::property (this=0x2f8fb60,
uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#13 0x00007ff2b51ebee2 in Nepomuk::Resource::property (this=<value optimized
out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#14 0x00007ff2b51ee9d0 in Nepomuk::Resource::rating (this=0x7ff2949dfc80) at
../../../nepomuk/core/resource.cpp:800
#15 0x0000000000465b08 in KLoadMetaDataThread::run (this=0x2bba110) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

bug #235365 QBasicAtomicInt::fetchAndAddOrdered

#6  0x0151301b in QBasicAtomicInt::fetchAndAddOrdered (this=0xb58095c0) at
../../include/QtCore/../../src/corelib/arch/qatomic_i386.h:163
#7  QBasicAtomicInt::fetchAndAddAcquire (this=0xb58095c0) at
../../include/QtCore/../../src/corelib/arch/qatomic_i386.h:296
#8  QMutex::lock (this=0xb58095c0) at thread/qmutex.cpp:158
#9  0x0097a000 in ?? () from /usr/lib/libsopranoclient.so.1
#10 0x00a93a30 in Nepomuk::MainModel::executeQuery (this=0x958ca20, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
../../../nepomuk/core/nepomukmainmodel.cpp:213
#11 0x004b63cd in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#12 0x00a87335 in Nepomuk::ResourceData::determineUri (this=0xb5811920) at
../../../nepomuk/core/resourcedata.cpp:671
#13 0x00a886a0 in Nepomuk::ResourceData::load (this=0xb5811920) at
../../../nepomuk/core/resourcedata.cpp:414
#14 0x00a8919b in Nepomuk::ResourceData::property (this=0xb5811920, uri=...) at
../../../nepomuk/core/resourcedata.cpp:271
#15 0x00aa6cb7 in Nepomuk::Resource::property (this=0xb262a294, uri=...) at
../../../nepomuk/core/resource.cpp:280
#16 0x00aa9d41 in Nepomuk::Resource::rating (this=0xb262a294) at
../../../nepomuk/core/resource.cpp:800
#17 0x080aa1e9 in KLoadMetaDataThread::run (this=0x9872250) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

bug #235435 Soprano::QueryResultIterator::binding

#5  0x00007f3139245e12 in ?? () from /usr/lib/libsopranoclient.so.1
#6  0x00007f3139245a22 in ?? () from /usr/lib/libsopranoclient.so.1
#7  0x00007f313dc66c17 in Soprano::QueryResultIterator::binding(QString const&)
const () from /usr/lib/libsoprano.so.4
#8  0x00007f313dc66dd9 in Soprano::QueryResultIterator::operator[](QString)
const () from /usr/lib/libsoprano.so.4
#9  0x00007f313df4ca21 in Nepomuk::ResourceData::load (this=<value optimized
out>) at ../../../nepomuk/core/resourcedata.cpp:420
#10 0x00007f313df4d1b8 in Nepomuk::ResourceData::property (this=0x7f3128108db0,
uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#11 0x00007f313df67ee2 in Nepomuk::Resource::property (this=<value optimized
out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#12 0x00007f313df6a9d0 in Nepomuk::Resource::rating (this=0x7f312c9e5c80) at
../../../nepomuk/core/resource.cpp:800
#13 0x0000000000465c1d in KLoadMetaDataThread::run (this=0x22137a0) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:92

bug #235692 QThreadStorageData::get

#5  QThreadStorageData::get (this=0x12) at thread/qthreadstorage.cpp:110
#6  0x00007f8398b115e3 in ?? () from /usr/lib/libsopranoclient.so.1
#7  0x00007f839d826ac4 in init (this=0x16daed0, forced=192) at
../../../nepomuk/core/nepomukmainmodel.cpp:96
#8  0x00007f839d827bc2 in model (this=0x16daa20, query=..., language=<value
optimized out>, userQueryLanguage=<value optimized out>) at
../../../nepomuk/core/nepomukmainmodel.cpp:112
#9  Nepomuk::MainModel::executeQuery (this=0x16daa20, query=...,
language=<value optimized out>, userQueryLanguage=<value optimized out>) at
../../../nepomuk/core/nepomukmainmodel.cpp:214
#10 0x00007f839d55977c in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#11 0x00007f839d81c635 in Nepomuk::ResourceData::determineUri
(this=0x7f8388011450) at ../../../nepomuk/core/resourcedata.cpp:671
#12 0x00007f839d81d802 in Nepomuk::ResourceData::load (this=0x7f8388011450) at
../../../nepomuk/core/resourcedata.cpp:414
#13 0x00007f839d81e1b8 in Nepomuk::ResourceData::property (this=0x7f8388011450,
uri=...) at ../../../nepomuk/core/resourcedata.cpp:271
#14 0x00007f839d838ee2 in Nepomuk::Resource::property (this=<value optimized
out>, uri=...) at ../../../nepomuk/core/resource.cpp:280
#15 0x00007f839d83b9d0 in Nepomuk::Resource::rating (this=0x7f838d3bac80) at
../../../nepomuk/core/resource.cpp:800
#16 0x0000000000465b08 in KLoadMetaDataThread::run (this=0x18a6c60) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95

bug #236505 operator new, QMutex::QMutex, Private, Soprano::Error::ErrorCache::ErrorCache

#7  0xb5a3f20f in raise () from /lib/libc.so.6
#8  0xb5a40b27 in abort () from /lib/libc.so.6
#9  0xb5a7bc55 in __libc_message () from /lib/libc.so.6
#10 0xb5a81c8b in malloc_printerr () from /lib/libc.so.6
#11 0xb5a85002 in _int_malloc () from /lib/libc.so.6
#12 0xb5a8694a in malloc () from /lib/libc.so.6
#13 0xb5c52525 in operator new(unsigned int) () from /usr/lib/libstdc++.so.6
#14 0xb6788d02 in QMutex::QMutex(QMutex::RecursionMode) () from
/usr/lib/libQtCore.so.4
#15 0xb7428c00 in Private (this=<value optimized out>) at
/usr/src/debug/soprano-2.4.2/soprano/error.cpp:187
#16 Soprano::Error::ErrorCache::ErrorCache (this=<value optimized out>) at
/usr/src/debug/soprano-2.4.2/soprano/error.cpp:195
#17 0xb56bfeb2 in Soprano::DataStream::DataStream (this=0xaf560c04,
dev=0x887f130) at /usr/src/debug/soprano-2.4.2/server/datastream.cpp:36
#18 0xb56c8096 in Soprano::Client::ClientConnection::checkProtocolVersion
(this=0x817c978) at
/usr/src/debug/soprano-2.4.2/client/clientconnection.cpp:728
#19 0xb56c4c3d in Soprano::Client::LocalSocketClient::connect (this=0x832a80c,
name=...) at /usr/src/debug/soprano-2.4.2/client/localsocketclient.cpp:140
#20 0xb750b586 in (anonymous namespace)::GlobalModelContainer::init
(this=0x832a7f8, forced=false) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/nepomukmainmodel.cpp:101
#21 0xb7519b1d in model (this=<value optimized out>) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/nepomukmainmodel.cpp:112
#22 Nepomuk::MainModel::executeQuery (this=<value optimized out>) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/nepomukmainmodel.cpp:213
#23 0xb743b54f in Soprano::FilterModel::executeQuery (this=0x8101850,
query=..., language=3413, userQueryLanguage=...) at
/usr/src/debug/soprano-2.4.2/soprano/filtermodel.cpp:164
#24 0xb750f1b0 in Nepomuk::ResourceData::determineUri (this=0x833acf0) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/resourcedata.cpp:671
#25 0xb752871e in Nepomuk::ResourceData::load (this=0x833acf0) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/resourcedata.cpp:414
#26 0xb7529178 in Nepomuk::ResourceData::property (this=0x833acf0, uri=...) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/resourcedata.cpp:271
#27 0xb7529269 in Nepomuk::Resource::property (this=0xaf5612b4, uri=...) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/resource.cpp:280
#28 0xb752949d in Nepomuk::Resource::rating (this=0xaf5612b4) at
/usr/src/debug/kdelibs-4.4.2/nepomuk/core/resource.cpp:800

Crashes in the main thread

bug #235770 QMutex::lock (in main thread)

#5  0x00007f6d49fb68dc in QMutex::lock (this=0x7f6d2c015c50) at
thread/qmutex.cpp:150
#6  0x00007f6d47d2fadd in ?? () from /usr/lib/libsopranoclient.so.1
#7  0x00007f6d4ca41b9d in Nepomuk::MainModel::executeQuery (this=0x2821d30,
query=..., language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...)
    at ../../../nepomuk/core/nepomukmainmodel.cpp:213
#8  0x00007f6d4c77377c in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#9  0x00007f6d4ca36635 in Nepomuk::ResourceData::determineUri
(this=0x7f6d2d471180) at ../../../nepomuk/core/resourcedata.cpp:671
#10 0x00007f6d4ca387b7 in Nepomuk::ResourceData::store (this=0x7f6d2d471180) at
../../../nepomuk/core/resourcedata.cpp:308
#11 0x00007f6d4ca393b0 in Nepomuk::ResourceData::setProperty
(this=0x7f6d2d471180, uri=..., value=...) at
../../../nepomuk/core/resourcedata.cpp:473
#12 0x000000000046678b in Nepomuk::MassUpdateJob::slotNext (this=0x33c18e0) at
../../../../apps/dolphin/src/panels/information/nepomukmassupdatejob.cpp:104
#13 0x0000000000466830 in Nepomuk::MassUpdateJob::qt_metacall (this=0x33c18e0,
_c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=<value
optimized out>)
    at ./nepomukmassupdatejob_p.moc:72
#14 0x00007f6d4a0c2e3f in QMetaObject::activate (sender=0x33c1910, m=<value
optimized out>, local_signal_index=<value optimized out>, argv=0x1) at
kernel/qobject.cpp:3293
#15 0x00007f6d4a0bfa63 in QObject::event (this=0x33c1910, e=0x7fff84f0fc40) at
kernel/qobject.cpp:1212
#16 0x00007f6d4ac9d22c in QApplicationPrivate::notify_helper (this=0x1794a40,
receiver=0x33c1910, e=0x7fff84f0fc40) at kernel/qapplication.cpp:4300
#17 0x00007f6d4aca36fb in QApplication::notify (this=0x7fff84f0ff90,
receiver=0x33c1910, e=0x7fff84f0fc40) at kernel/qapplication.cpp:4183
#18 0x00007f6d4b9a8526 in KApplication::notify (this=0x7fff84f0ff90,
receiver=0x33c1910, event=0x7fff84f0fc40) at
../../kdeui/kernel/kapplication.cpp:302
#19 0x00007f6d4a0b006c in QCoreApplication::notifyInternal
(this=0x7fff84f0ff90, receiver=0x33c1910, event=0x7fff84f0fc40) at
kernel/qcoreapplication.cpp:704
#20 0x00007f6d4a0dcd42 in QCoreApplication::sendEvent (this=0x17998a0) at
../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#21 QTimerInfoList::activateTimers (this=0x17998a0) at
kernel/qeventdispatcher_unix.cpp:603
#22 0x00007f6d4a0d9848 in timerSourceDispatch (source=<value optimized out>) at
kernel/qeventdispatcher_glib.cpp:184
#23 idleTimerSourceDispatch (source=<value optimized out>) at
kernel/qeventdispatcher_glib.cpp:231
#24 0x00007f6d45da88c2 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#25 0x00007f6d45dac748 in ?? () from /lib/libglib-2.0.so.0
#26 0x00007f6d45dac8fc in g_main_context_iteration () from
/lib/libglib-2.0.so.0
#27 0x00007f6d4a0d9513 in QEventDispatcherGlib::processEvents (this=0x176d770,
flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#28 0x00007f6d4ad4d46e in QGuiEventDispatcherGlib::processEvents
(this=0x7f6d2c015c50, flags=<value optimized out>) at
kernel/qguieventdispatcher_glib.cpp:204
#29 0x00007f6d4a0ae992 in QEventLoop::processEvents (this=<value optimized
out>, flags=) at kernel/qeventloop.cpp:149
#30 0x00007f6d4a0aed6c in QEventLoop::exec (this=0x7fff84f0fee0, flags=) at
kernel/qeventloop.cpp:201
#31 0x00007f6d4a0b2aab in QCoreApplication::exec () at
kernel/qcoreapplication.cpp:981
#32 0x000000000043b1c5 in main (argc=<value optimized out>, argv=<value
optimized out>) at ../../../../apps/dolphin/src/main.cpp:101

Crashes in the main thread in non-Nepomuk/Soprano code

There are many reports where the crash occurs in the main thread in code that looks unrelated to Nepomuk/Soprano, but since the backtraces have a couple of KLoadMetaDataThreads which are locked in Mutexes, and they started showing up at the same time as the crashes above, they might be related anyway. The crashes often occur in malloc/realloc/free which might point to a memory corruption issue (maybe caused by Nepomuk/Soprano)?

Some typical examples:

bug #234928 Crash in malloc

#7  0x00b0e651 in raise () from /lib/tls/i686/cmov/libc.so.6
#8  0x00b11a82 in abort () from /lib/tls/i686/cmov/libc.so.6
#9  0x00b4549d in ?? () from /lib/tls/i686/cmov/libc.so.6
#10 0x00b4f591 in ?? () from /lib/tls/i686/cmov/libc.so.6
#11 0x00b52c10 in ?? () from /lib/tls/i686/cmov/libc.so.6
#12 0x00b53f9c in malloc () from /lib/tls/i686/cmov/libc.so.6
#13 0x0749bb8d in qMalloc (size=12) at global/qmalloc.cpp:55
#14 0x074bf403 in QHashData::allocateNode (this=0x9996758, nodeAlign=4) at
tools/qhash.cpp:179
#15 0x084a6d05 in QHash<QByteArray, QHashDummyValue>::createNode () at
../../include/QtCore/../../src/corelib/tools/qhash.h:540
#16 QHash<QByteArray, QHashDummyValue>::insert () at
../../include/QtCore/../../src/corelib/tools/qhash.h:756
#17 QSet<QByteArray>::insert () at
../../include/QtCore/../../src/corelib/tools/qset.h:176
#18 QSet<QByteArray>::operator<< () at
../../include/QtCore/../../src/corelib/tools/qset.h:197
#19 QImageReader::supportedImageFormats () at image/qimagereader.cpp:1412
#20 0x083db706 in imageReadMimeFormats () at kernel/qdnd.cpp:501
#21 0x083dcb54 in QInternalMimeData::formats (this=0x9aafb30) at
kernel/qdnd.cpp:561
#22 0x0845e151 in QClipboardWatcher::retrieveData_sys (this=0x9aafb30, fmt=...,
requestedType=QVariant::ByteArray) at kernel/qclipboard_x11.cpp:1247
#23 0x083dbff7 in QInternalMimeData::retrieveData (this=0x9aafb30,
mimeType=..., type=QVariant::ByteArray) at kernel/qdnd.cpp:574
#24 0x075b097a in QMimeDataPrivate::retrieveTypedData (this=0x9a36950,
format=..., type=QVariant::ByteArray) at kernel/qmimedata.cpp:107
#25 0x075b12b1 in QMimeData::data (this=0x9aafb30, mimeType=...) at
kernel/qmimedata.cpp:524
#26 0x008b2884 in KFilePreviewGenerator::Private::decodeIsCutSelection
(this=0x96018c0, mimeData=0x9aafb30) at
../../kfile/kfilepreviewgenerator.cpp:1061

[...]

bug #235464 Crash in realloc

#5  0x00007f89603f0a75 in *__GI_raise (sig=<value optimized out>) at
../nptl/sysdeps/unix/sysv/linux/raise.c:64
#6  0x00007f89603f45c0 in *__GI_abort () at abort.c:92
#7  0x00007f896042a4fb in __libc_message (do_abort=<value optimized out>,
fmt=<value optimized out>) at ../sysdeps/unix/sysv/linux/libc_fatal.c:189
#8  0x00007f89604345b6 in malloc_printerr (action=3, str=0x7f89605067f8
"malloc(): smallbin double linked list corrupted", ptr=<value optimized out>)
at malloc.c:6264
#9  0x00007f89604388e9 in _int_malloc (av=0x7f894c000020, bytes=113) at
malloc.c:4306
#10 0x00007f896043ab22 in _int_realloc (av=0x7f894c000020, oldp=0x7f894c02eda0,
oldsize=<value optimized out>, nb=128) at malloc.c:5271
#11 0x00007f896043b080 in *__GI___libc_realloc (oldmem=0x7f894c02edb0,
bytes=112) at malloc.c:3821
#12 0x00007f89618ecb14 in QVector<QPainterPath::Element>::realloc
(this=0x7f894c049ca8, asize=2, aalloc=4) at
../../include/QtCore/../../src/corelib/tools/qvector.h:479
#13 0x00007f896191df47 in
QVector<QPainterPath::Element>::append(QPainterPath::Element const&) () from
/usr/lib/libQtGui.so.4
#14 0x00007f89619186ca in QPainterPath::lineTo (this=<value optimized out>,
p=...) at painting/qpainterpath.cpp:690
#15 0x00007f89619b46fb in QX11PaintEngine::drawPolygon (this=0x7f894c05ef40,
polygonPoints=<value optimized out>, pointCount=4, mode=<value optimized out>)
at painting/qpaintengine_x11.cpp:1707
#16 0x00007f896190ad06 in QPainter::drawPolygon (this=<value optimized out>,
points=0x7fff3a7597f0, pointCount=4, fillRule=Qt::OddEvenFill) at
painting/qpainter.cpp:4937
#17 0x00007f89593c8b73 in OxygenStyle::standardIconImplementation (this=<value
optimized out>, standardIcon=<value optimized out>, option=<value optimized
out>, widget=<value optimized out>)
    at ../../../kstyles/oxygen/oxygen.cpp:6561
[...]

bug #236021 Crash in free

#5  0x00007f0e31fe9a75 in *__GI_raise (sig=<value optimized out>) at
../nptl/sysdeps/unix/sysv/linux/raise.c:64
#6  0x00007f0e31fed5c0 in *__GI_abort () at abort.c:92
#7  0x00007f0e320234fb in __libc_message (do_abort=<value optimized out>,
fmt=<value optimized out>) at ../sysdeps/unix/sysv/linux/libc_fatal.c:189
#8  0x00007f0e3202d5b6 in malloc_printerr (action=3, str=0x7f0e320ff560
"free(): invalid next size (fast)", ptr=<value optimized out>) at malloc.c:6264
#9  0x00007f0e32033e53 in *__GI___libc_free (mem=<value optimized out>) at
malloc.c:3738
#10 0x00007f0e327d15ce in QList<QObject*>::free (this=0x7f0e180331f8) at
../../include/QtCore/../../src/corelib/tools/qlist.h:649
#11 QList<QObject*>::operator= (this=0x7f0e180331f8) at
../../include/QtCore/../../src/corelib/tools/qlist.h:413
#12 QList<QObject*>::clear (this=0x7f0e180331f8) at
../../include/QtCore/../../src/corelib/tools/qlist.h:656
#13 0x00007f0e327c999f in QObjectPrivate::sendPendingChildInsertedEvents
(this=0x7f0e18033190) at kernel/qobject.cpp:199
#14 0x00007f0e327c9d89 in QObject::event (this=0x7f0e18033110,
e=0x7f0e180243f0) at kernel/qobject.cpp:1217
#15 0x00007f0e333a722c in QApplicationPrivate::notify_helper (this=0x1897ca0,
receiver=0x7f0e18033110, e=0x7f0e180243f0) at kernel/qapplication.cpp:4300
[...]

bug #236215 Crash in operator delete - note the Soprano error in thread 6

Thread 6 (Thread 0xb0ea0b70 (LWP 24100)):
#0  0x0025b422 in __kernel_vsyscall ()
#1  0x0046daf9 in __lll_lock_wait () from /lib/tls/i686/cmov/libpthread.so.0
#2  0x0046913b in _L_lock_748 () from /lib/tls/i686/cmov/libpthread.so.0
#3  0x00468f61 in pthread_mutex_lock () from /lib/tls/i686/cmov/libpthread.so.0
#4  0x0921db66 in pthread_mutex_lock () from /lib/tls/i686/cmov/libc.so.6
#5  0x0164b76c in QMutexPrivate::wait (this=0x9635cc0, timeout=-1) at
thread/qmutex_unix.cpp:80
#6  0x01647052 in QMutex::lock (this=0x94de62c) at thread/qmutex.cpp:167
#7  0x00682b38 in Soprano::Error::ErrorCache::clearError() const () from
/usr/lib/libsoprano.so.4
#8  0x006831c3 in Soprano::Error::ErrorCache::setError(Soprano::Error::Error
const&) const () from /usr/lib/libsoprano.so.4
#9  0x0042af66 in ?? () from /usr/lib/libsopranoclient.so.1
#10 0x00da8a30 in Nepomuk::MainModel::executeQuery (this=0x9656920, query=...,
language=Soprano::Query::QueryLanguageSparql, userQueryLanguage=...) at
../../../nepomuk/core/nepomukmainmodel.cpp:213
#11 0x006933cd in Soprano::FilterModel::executeQuery(QString const&,
Soprano::Query::QueryLanguage, QString const&) const () from
/usr/lib/libsoprano.so.4
#12 0x00d9c335 in Nepomuk::ResourceData::determineUri (this=0xb563b9f0) at
../../../nepomuk/core/resourcedata.cpp:671
#13 0x00d9d6a0 in Nepomuk::ResourceData::load (this=0xb563b9f0) at
../../../nepomuk/core/resourcedata.cpp:414
#14 0x00d9e19b in Nepomuk::ResourceData::property (this=0xb563b9f0, uri=...) at
../../../nepomuk/core/resourcedata.cpp:271
#15 0x00dbbcb7 in Nepomuk::Resource::property (this=0xb0ea0294, uri=...) at
../../../nepomuk/core/resource.cpp:280
#16 0x00dbed41 in Nepomuk::Resource::rating (this=0xb0ea0294) at
../../../nepomuk/core/resource.cpp:800
#17 0x080aa1e9 in KLoadMetaDataThread::run (this=0x96889a0) at
../../../../apps/dolphin/src/panels/information/kloadmetadatathread.cpp:95
[...]

Thread 1 (Thread 0xb77b1710 (LWP 24032)):
[KCrash Handler]
#6  0x0025b422 in __kernel_vsyscall ()
#7  0x0916d651 in raise () from /lib/tls/i686/cmov/libc.so.6
#8  0x09170a82 in abort () from /lib/tls/i686/cmov/libc.so.6
#9  0x091a449d in ?? () from /lib/tls/i686/cmov/libc.so.6
#10 0x091ae591 in ?? () from /lib/tls/i686/cmov/libc.so.6
#11 0x091af80e in ?? () from /lib/tls/i686/cmov/libc.so.6
#12 0x007e9741 in operator delete(void*) () from /usr/lib/libstdc++.so.6
#13 0x0171c711 in ~QFSFileEngine (this=0xbfe0cd68, __in_chrg=<value optimized
out>) at io/qfsfileengine.cpp:252
#14 0x016d9b06 in ~Data (this=0x94de628, __in_chrg=<value optimized out>) at
io/qfileinfo_p.h:90
#15 ~QFileInfoPrivate (this=0x94de628, __in_chrg=<value optimized out>) at
io/qfileinfo.cpp:68
#16 0x016da0fb in QScopedPointerDeleter<QFileInfoPrivate>::cleanup
(this=0xbfe0d418, __in_chrg=<value optimized out>) at
../../include/QtCore/../../src/corelib/tools/qscopedpointer.h:62
#17 ~QScopedPointer (this=0xbfe0d418, __in_chrg=<value optimized out>) at
../../include/QtCore/../../src/corelib/tools/qscopedpointer.h:100
#18 ~QFileInfo (this=0xbfe0d418, __in_chrg=<value optimized out>) at
io/qfileinfo.cpp:374
#19 0x01283193 in cleanpath (_path=..., cleanDirSeparator=true,
decodeDots=<value optimized out>) at ../../kdecore/io/kurl.cpp:56
#20 0x01284b55 in KUrl::cleanPath (this=0xbfe0d654, options=@0xbfe0d4bc) at
../../kdecore/io/kurl.cpp:733
#21 0x00a4f39e in cleanupUrl (url=<value optimized out>) at
../../kio/kio/kdirmodel.cpp:48
#22 0x00a51bb4 in KDirModelPrivate::_k_slotNewItems (this=0x9628b20,
directoryUrl=..., items=...) at ../../kio/kio/kdirmodel.cpp:414
#23 0x00a54d97 in KDirModel::qt_metacall (this=0x962d028,
_c=QMetaObject::InvokeMetaMethod, _id=26, _a=0xbfe0d834) at ./kdirmodel.moc:88
#24 0x004c846a in DolphinModel::qt_metacall (this=0x962d028,
_c=QMetaObject::InvokeMetaMethod, _id=26, _a=0xbfe0d834) at
moc_dolphinmodel.cpp:68
#25 0x01753c9a in QMetaObject::metacall (object=0x962d028, cl=24032, idx=26,
argv=0xbfe0d834) at kernel/qmetaobject.cpp:237
#26 0x017623d5 in QMetaObject::activate (sender=0x962cf08, m=0x80cd540,
local_signal_index=10, argv=0xbfe0d834) at kernel/qobject.cpp:3293
#27 0x00a35379 in KDirLister::itemsAdded (this=0x962cf08, _t1=..., _t2=...) at
./kdirlister.moc:274
[...]

bug #235962 Crash in KIO::SimpleJob::url

#6  KIO::SimpleJob::url (this=0x8b0bb70) at ../../kio/kio/job.cpp:338
#7  0x00bac60d in KIO::SchedulerPrivate::startJobScheduled (this=0x8b0bb70,
protInfo=0x8c89fb8) at ../../kio/kio/scheduler.cpp:626
#8  0x00bacaf1 in KIO::SchedulerPrivate::startStep (this=0x8b0bb70) at
../../kio/kio/scheduler.cpp:534
#9  0x00bacd55 in KIO::Scheduler::qt_metacall (this=0x8acd168,
_c=QMetaObject::InvokeMetaMethod, _id=6, _a=0xbfa099dc) at ./scheduler.moc:108
#10 0x082dcc9a in QMetaObject::metacall (object=0x8acd168,
cl=QMetaObject::InvokeMetaMethod, idx=10, argv=0xbfa099dc) at
kernel/qmetaobject.cpp:237
#11 0x082eb3d5 in QMetaObject::activate (sender=0x8b0bb74, m=0x83eb5a4,
local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3293
#12 0x0833caa7 in QTimer::timeout (this=0x8b0bb74) at
.moc/release-shared/moc_qtimer.cpp:134
#13 0x082f360e in QTimer::timerEvent (this=0x8b0bb74, e=0xbfa09f10) at
kernel/qtimer.cpp:271
#14 0x082e8254 in QObject::event (this=0x8b0bb74, e=0xbfa0987f) at
kernel/qobject.cpp:1212
#15 0x0631c4dc in QApplicationPrivate::notify_helper (this=0x8984ff0,
receiver=0x8b0bb74, e=0xbfa09f10) at kernel/qapplication.cpp:4300
[...]