Bug 244891

*** Bug 245578 has been marked as a duplicate of this bug. ***

*** Bug 250877 has been marked as a duplicate of this bug. ***

*** Bug 257553 has been marked as a duplicate of this bug. ***

*** Bug 273396 has been marked as a duplicate of this bug. ***

*** Bug 283726 has been marked as a duplicate of this bug. ***

*** Bug 285829 has been marked as a duplicate of this bug. ***

*** Bug 287728 has been marked as a duplicate of this bug. ***

Created attachment 73164 [details]
New crash information added by DrKonqi

systemsettings (1.0) on KDE Platform 4.8.4 (4.8.4) using Qt 4.8.1

- What I was doing when the application crashed:

- Custom settings of the application:

i pluged my Canon EOS 550D then I opened configuration settings and appareil photo. I  tested it with the bottom test. I clicked on configurer and then crached. At every time that i have make this actions

-- Backtrace (Reduced):
#6  __strcmp_sse42 () at ../sysdeps/x86_64/multiarch/strcmp-sse42.S:163
#7  0x00007f7d63ca630d in KameraConfigDialog::appendWidget (this=0x7fff1c8dd010, parent=0x1ab8570, widget=0x1e78710) at ../../kcontrol/kameraconfigdialog.cpp:192
#8  0x00007f7d63ca5adc in KameraConfigDialog::appendWidget (this=0x7fff1c8dd010, parent=<optimized out>, widget=0x1e47dd0) at ../../kcontrol/kameraconfigdialog.cpp:251
#9  0x00007f7d63ca5adc in KameraConfigDialog::appendWidget (this=0x7fff1c8dd010, parent=<optimized out>, widget=0x1e57de0) at ../../kcontrol/kameraconfigdialog.cpp:251
#10 0x00007f7d63ca67c3 in KameraConfigDialog::KameraConfigDialog (this=0x7fff1c8dd010, widget=0x1e57de0, parent=<optimized out>, name=<optimized out>) at ../../kcontrol/kameraconfigdialog.cpp:64

W dniu 2012-08-14 12:19, charpentier Franck pisze:
> https://bugs.kde.org/show_bug.cgi?id=244891
>
> --- Comment #8 from charpentier Franck <charpentier.franck@gmail.com> ---
> Created attachment 73164 [details]
>    --> https://bugs.kde.org/attachment.cgi?id=73164&action=edit
> New crash information added by DrKonqi
>
> systemsettings (1.0) on KDE Platform 4.8.4 (4.8.4) using Qt 4.8.1
>
> - What I was doing when the application crashed:
>
> - Custom settings of the application:
>
> i pluged my Canon EOS 550D then I opened configuration settings and appareil
> photo. I  tested it with the bottom test. I clicked on configurer and then
> crached. At every time that i have make this actions
>
> -- Backtrace (Reduced):
> #6  __strcmp_sse42 () at ../sysdeps/x86_64/multiarch/strcmp-sse42.S:163
> #7  0x00007f7d63ca630d in KameraConfigDialog::appendWidget
> (this=0x7fff1c8dd010, parent=0x1ab8570, widget=0x1e78710) at
> ../../kcontrol/kameraconfigdialog.cpp:192
> #8  0x00007f7d63ca5adc in KameraConfigDialog::appendWidget
> (this=0x7fff1c8dd010, parent=<optimized out>, widget=0x1e47dd0) at
> ../../kcontrol/kameraconfigdialog.cpp:251
> #9  0x00007f7d63ca5adc in KameraConfigDialog::appendWidget
> (this=0x7fff1c8dd010, parent=<optimized out>, widget=0x1e57de0) at
> ../../kcontrol/kameraconfigdialog.cpp:251
> #10 0x00007f7d63ca67c3 in KameraConfigDialog::KameraConfigDialog
> (this=0x7fff1c8dd010, widget=0x1e57de0, parent=<optimized out>, name=<optimized
> out>) at ../../kcontrol/kameraconfigdialog.cpp:64
>
?

*** Bug 322007 has been marked as a duplicate of this bug. ***

Weird, as it does not reproduce for me :/

if anyone could output the values at that crash site it would be nice

gdb kcmshell4
(gdb) r kamera
... reproduce crash ... 

go to the frame wiht  ../../kcontrol/kameraconfigdialog.cpp:192  and then

(gdb) info locals

(gdb) print widget_value_string

(gdb) print widget_choice


I need to see why                                 if(!strcmp(widget_value_string, widget_choice))
crashes :/

Hello,
   here-after the gdb report. It shows that  widget_value_string[0] = 0
   Have a nice day
Alain

GDB report:
Reading symbols from /usr/bin/kcmshell4...Reading symbols from 
/usr/lib/debug/usr/bin/kcmshell4.debug...done.
done.
(gdb) r kamera
Starting program: /usr/bin/kcmshell4 kamera
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
__strcmp_sse2 () at ../sysdeps/x86_64/strcmp.S:212
212             movlpd  (%rdi), %xmm1
Missing separate debuginfos, use: debuginfo-install 
expat-2.1.0-4.fc18.x86_64 ibus-qt-1.3.2-2.fc18.x86_64 
jbigkit-libs-2.0-7.fc18.x86_64 kde-workspace-libs-4.10.4-5.fc18.x86_64 
keyutils-libs-1.5.5-3.fc18.x86_64 lcms-libs-1.19-7.fc18.x86_64 
libXdmcp-1.1.1-2.fc18.x86_64 libffi-3.0.10-3.fc18.x86_64 
libicu-49.1.1-8.fc18.x86_64 libselinux-2.1.12-7.3.fc18.x86_64 
libtool-ltdl-2.4.2-7.fc18.x86_64 libuuid-2.22.2-6.fc18.x86_64 
libxcb-1.9-3.fc18.x86_64
(gdb) backtrace
#0  __strcmp_sse2 () at ../sysdeps/x86_64/strcmp.S:212
#1  0x00007fffed54b977 in KameraConfigDialog::appendWidget 
(this=this@entry=0x7fffffffc330, parent=parent@entry=0x8914f0,
     widget=0xb380b0) at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameraconfigdialog.cpp:185
#2  0x00007fffed54b284 in KameraConfigDialog::appendWidget 
(this=this@entry=0x7fffffffc330, parent=parent@entry=0xadc610,
     widget=0xb373d0) at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameraconfigdialog.cpp:244
#3  0x00007fffed54b284 in KameraConfigDialog::appendWidget 
(this=this@entry=0x7fffffffc330, parent=parent@entry=0xadc610,
     widget=widget@entry=0xae5950) at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameraconfigdialog.cpp:244
#4  0x00007fffed54be92 in KameraConfigDialog::KameraConfigDialog 
(this=0x7fffffffc330, widget=0xae5950,
     parent=<optimized out>) at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameraconfigdialog.cpp:62
#5  0x00007fffed548a0a in KCamera::configure (this=0xbb7bc0) at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameradevice.cpp:173
#6  0x00007fffed546689 in KKameraConfig::slot_configureCamera 
(this=0x7b12f0)
     at /usr/src/debug/kamera-4.10.4/kcontrol/kamera.cpp:362
#7  0x00000032e5b8cd6f in QMetaObject::activate (sender=0x7bb960, 
m=<optimized out>, local_signal_index=<optimized out>,
     argv=0x7fffffffc590) at kernel/qobject.cpp:3539
#8  0x0000003883fc4412 in QAction::triggered (this=this@entry=0x7bb960, 
_t1=false)
     at .moc/release-shared/moc_qaction.cpp:276
#9  0x0000003883fc4600 in QAction::activate (this=0x7bb960, 
event=<optimized out>) at kernel/qaction.cpp:1257
#10 0x000000388438424f in QAbstractButtonPrivate::click 
(this=this@entry=0x7bbfd0) at widgets/qabstractbutton.cpp:530
#11 0x00000038843844fc in QAbstractButton::mouseReleaseEvent 
(this=0x968cc0, e=0x7fffffffce40)
     at widgets/qabstractbutton.cpp:1123
#12 0x000000388443e78a in QToolButton::mouseReleaseEvent 
(this=<optimized out>, e=<optimized out>)
     at widgets/qtoolbutton.cpp:718
#13 0x0000003884019f49 in QWidget::event (this=0x968cc0, 
event=0x7fffffffce40) at kernel/qwidget.cpp:8375
#14 0x0000003883fca5cc in QApplicationPrivate::notify_helper 
(this=0x63cda0, receiver=0x968cc0, e=0x7fffffffce40)
     at kernel/qapplication.cpp:4562
#15 0x0000003883fcf2ab in QApplication::notify (this=<optimized out>, 
receiver=0x968cc0, e=0x7fffffffce40)
     at kernel/qapplication.cpp:4105
#16 0x0000003f88a46f16 in KApplication::notify (this=0x7fffffffdc50, 
receiver=0x968cc0, event=0x7fffffffce40)
     at /usr/src/debug/kdelibs-4.10.4/kdeui/kernel/kapplication.cpp:311
#17 0x00000032e5b7793e in QCoreApplication::notifyInternal 
(this=0x7fffffffdc50, receiver=0x968cc0, event=0x7fffffffce40)
     at kernel/qcoreapplication.cpp:949
#18 0x0000003883fcb40b in QApplicationPrivate::sendMouseEvent 
(receiver=0x968cc0, event=0x7fffffffce40,
     alienWidget=0x968cc0, nativeWidget=0x9412d0, 
buttonDown=0x3884a9e268 <qt_button_down>, lastMouseReceiver=...,
     spontaneous=true) at ../../src/corelib/kernel/qcoreapplication.h:231
#19 0x0000003884045b74 in QETWidget::translateMouseEvent (this=0x9412d0, 
event=<optimized out>)
     at kernel/qapplication_x11.cpp:4537
#20 0x0000003884044901 in QApplication::x11ProcessEvent 
(this=0x7fffffffdc50, event=0x7fffffffd5b0)
     at kernel/qapplication_x11.cpp:3660
#21 0x000000388406aa5c in x11EventSourceDispatch (s=s@entry=0x63df00, 
callback=0x0, user_data=0x0)
     at kernel/qguieventdispatcher_glib.cpp:148
#22 0x00000032da647a55 in g_main_dispatch (context=0x633780) at gmain.c:2715
#23 g_main_context_dispatch (context=context@entry=0x633780) at gmain.c:3219
#24 0x00000032da647d88 in g_main_context_iterate 
(context=context@entry=0x633780, block=block@entry=1,
     dispatch=dispatch@entry=1, self=<optimized out>) at gmain.c:3290
---Type <return> to continue, or q <return> to quit---
#25 0x00000032da647e44 in g_main_context_iteration (context=0x633780, 
may_block=1) at gmain.c:3351
#26 0x00000032e5ba5fa6 in QEventDispatcherGlib::processEvents 
(this=0x609770, flags=...)
     at kernel/qeventdispatcher_glib.cpp:426
#27 0x000000388406a73e in QGuiEventDispatcherGlib::processEvents 
(this=<optimized out>, flags=...)
     at kernel/qguieventdispatcher_glib.cpp:207
#28 0x00000032e5b765ef in QEventLoop::processEvents 
(this=this@entry=0x7fffffffd990, flags=...)
     at kernel/qeventloop.cpp:149
#29 0x00000032e5b76878 in QEventLoop::exec (this=0x7fffffffd990, 
flags=...) at kernel/qeventloop.cpp:204
#30 0x000000388447e3f8 in QDialog::exec (this=0x7ee050) at 
dialogs/qdialog.cpp:554
#31 0x0000003794807cec in kdemain (_argc=6422624, _argv=<optimized out>)
     at /usr/src/debug/kde-runtime-4.10.4/kcmshell/main.cpp:297
#32 0x00000032d7a21a05 in __libc_start_main (main=0x400790 <main(int, 
char**)>, argc=2, ubp_av=0x7fffffffdd88,
     init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized 
out>, stack_end=0x7fffffffdd78) at libc-start.c:225
#33 0x00000000004007c1 in _start ()
#1  0x00007fffed54b977 in KameraConfigDialog::appendWidget 
(this=this@entry=0x7fffffffc330, parent=parent@entry=0x8914f0,
     widget=0xb380b0) at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameraconfigdialog.cpp:185
185 if(!strcmp(widget_value_string, widget_choice))
(gdb) frame 1 # ATH: at 
/usr/src/debug/kamera-4.10.4/kcontrol/kameraconfigdialog.cpp:185
(gdb) info locals
widget_choice = 0xbc8280 "P"
i = 0
count = 16
buttonGroup = 0xd94290
widget_type = <optimized out>
widget_info = 0xb381b4 ""
widget_value_int = <optimized out>
whats_this = {static null = {<No data fields>}, static shared_null = 
{ref = {_q_value = 5332}, alloc = 0, size = 0,
     data = 0x32e5ed491a <QString::shared_null+26>, clean = 0, 
simpletext = 0, righttoleft = 0, asciiCache = 0,
     capacity = 0, reserved = 0, array = {0}}, static shared_empty = 
{ref = {_q_value = 77}, alloc = 0, size = 0,
     data = 0x32e5ed48fa <QString::shared_empty+26>, clean = 0, 
simpletext = 0, righttoleft = 0, asciiCache = 0,
     capacity = 0, reserved = 0, array = {0}}, d = 0x32e5ed48e0 
<QString::shared_empty>, static codecForCStrings = 0x0}
newParent = 0x8914f0
widget_name = 0xb385b4 "autoexposuremode"
widget_label = 0xb380b4 "Mode d'exposition automatique Canon"
widget_value_float = <optimized out>
widget_value_string = 0x0
(gdb) print widget_choice
$2 = 0xbc8280 "P"



Marcus Meissner wrote:
> https://bugs.kde.org/show_bug.cgi?id=244891
>
> --- Comment #11 from Marcus Meissner<marcus@jet.franken.de>  ---
> Weird, as it does not reproduce for me :/
>
> if anyone could output the values at that crash site it would be nice
>
> gdb kcmshell4
> (gdb) r kamera
> ... reproduce crash ...
>
> go to the frame wiht  ../../kcontrol/kameraconfigdialog.cpp:192  and then
>
> (gdb) info locals
>
> (gdb) print widget_value_string
>
> (gdb) print widget_choice
>
>
> I need to see why
> if(!strcmp(widget_value_string, widget_choice))
> crashes :/
>

This could happen when the value of a configuration widget was not set, e.g. in some
cases where the value was unknown.

I was hoping libgphoto2 always sets the value, but apparently there are some side cases where it did not (or does not).

I have applied a patch to kamera GIT to handle this case.

Created attachment 81005 [details]
patch to handle unset variables

patch i applied to current kamera GIT, checking for NULL ptr

Marcus, the patch looks good.

To get more testing, I would suggest to commit it to 4.11 branch and master.

comment #13 is a good new (for segmentation fault) but I think it hides a most serious problem.
if you look at the end of comment 13, there is a very strange value for a widget_name : 0xb385b4 "autoexposuremode" . This value is an EXIF data embeded in an plain photo or a thumbnail  . All happens as if 2 apps (Kamera and maybe digikam) were accessing the EOS 7D at the same time 
an it's would be a very bad idea to do this. My opinion is this is a share resource problem or if the camera can't be shared, a locking default.

I thought I had it applied and pushed... but I seem to have forgot the push :)

pushed now, to master and KDE/4.11

alainthiaville59 ... (re #c16)

this is a camera setting that can be changed in the kamera configure dialog.

2 apps cannot access the camera at the same time, the protocol in use does not really know about multiple session over a single usb bus.

The second app trying to access it should get a "camera already in use" error already.