[Bug]: Crash in RvApplication::newSessionFromFiles while multiple displays are connected.

[pjurkas]

What happened?

Some users are experiencing OpenRV crashing at startup (SIGSEGV) when multiple monitors are connected to theirs' computers. I was trying to reproduce it on my machine, but I was not successfull. It might depend on how the monitors are setup in GNOME config. This is the callstack at the SIGSEGV:

#0  0x00007ffff7386230 in QScreen::geometry() const () at /spfs/lib/openrv/lib/libQt5Gui.so.5
#1  0x00000000008cd4a8 in Rv::RvApplication::newSessionFromFiles(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&) ()
#2  0x00000000008cd995 in Rv::RvApplication::runCreateSession() ()
#3  0x00007ffff6f7924d in ??? () at /spfs/lib/openrv/lib/libQt5Core.so.5
#4  0x00007ffff6f7cf3a in QTimer::timeout(QTimer::QPrivateSignal) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#5  0x00007ffff6f6f61f in QObject::event(QEvent*) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#6  0x00007ffff7a47b6f in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /spfs/lib/openrv/lib/libQt5Widgets.so.5
#7  0x00007ffff6f44ef0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#8  0x00007ffff6f9837b in QTimerInfoList::activateTimers() () at /spfs/lib/openrv/lib/libQt5Core.so.5
#9  0x00007ffff6f98b54 in ??? () at /spfs/lib/openrv/lib/libQt5Core.so.5
#10 0x00007fffe9119f4f in g_main_context_dispatch () at /usr/lib64/libglib-2.0.so.0
#11 0x00007fffe916f268 in g_main_context_iterate.constprop () at /usr/lib64/libglib-2.0.so.0
#12 0x00007fffe9117713 in g_main_context_iteration () at /usr/lib64/libglib-2.0.so.0
#13 0x00007ffff6f98eb4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#14 0x00007ffff6f43a6b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#15 0x00007ffff6f4b67c in QCoreApplication::exec() () at /spfs/lib/openrv/lib/libQt5Core.so.5
#16 0x00000000008396e5 in utf8Main(int, char**) ()
#17 0x00007fffeb4295d0 in __libc_start_call_main () at /usr/lib64/libc.so.6
#18 0x00007fffeb429680 in __libc_start_main_impl () at /usr/lib64/libc.so.6
#19 0x0000000000831d25 in _start ()

Looks like some screen instance is nullptr when calling screen->geometry() inside RvApplication::newSessionFromFiles function.

List all the operating systems versions where this is happening

RHEL 9.5

On what computer hardware is this happening?

NVIDIA Corporation GA102GL [RTX A6000], Intel(R) Xeon(R) Gold 6226R CPU @ 2.90GHz, 64 cores, 187Gi RAM

Relevant console log output

#0  0x00007ffff7386230 in QScreen::geometry() const () at /spfs/lib/openrv/lib/libQt5Gui.so.5
#1  0x00000000008cd4a8 in Rv::RvApplication::newSessionFromFiles(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&) ()
#2  0x00000000008cd995 in Rv::RvApplication::runCreateSession() ()
#3  0x00007ffff6f7924d in ??? () at /spfs/lib/openrv/lib/libQt5Core.so.5
#4  0x00007ffff6f7cf3a in QTimer::timeout(QTimer::QPrivateSignal) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#5  0x00007ffff6f6f61f in QObject::event(QEvent*) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#6  0x00007ffff7a47b6f in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /spfs/lib/openrv/lib/libQt5Widgets.so.5
#7  0x00007ffff6f44ef0 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#8  0x00007ffff6f9837b in QTimerInfoList::activateTimers() () at /spfs/lib/openrv/lib/libQt5Core.so.5
#9  0x00007ffff6f98b54 in ??? () at /spfs/lib/openrv/lib/libQt5Core.so.5
#10 0x00007fffe9119f4f in g_main_context_dispatch () at /usr/lib64/libglib-2.0.so.0
#11 0x00007fffe916f268 in g_main_context_iterate.constprop () at /usr/lib64/libglib-2.0.so.0
#12 0x00007fffe9117713 in g_main_context_iteration () at /usr/lib64/libglib-2.0.so.0
#13 0x00007ffff6f98eb4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#14 0x00007ffff6f43a6b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /spfs/lib/openrv/lib/libQt5Core.so.5
#15 0x00007ffff6f4b67c in QCoreApplication::exec() () at /spfs/lib/openrv/lib/libQt5Core.so.5
#16 0x00000000008396e5 in utf8Main(int, char**) ()
#17 0x00007fffeb4295d0 in __libc_start_call_main () at /usr/lib64/libc.so.6
#18 0x00007fffeb429680 in __libc_start_main_impl () at /usr/lib64/libc.so.6
#19 0x0000000000831d25 in _start ()

Environment variables

No response

Extra information

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[pjurkas]

This issue is present in all versions of OpenRV >= 2.2.

[tiltX]

We've just experienced crashes with OpenRV 3.1.0 on Rocky Linux 9 which went away with just one monitor connected. But we found out something else because most workstations with 2 monitors were not experiencing any issues:
The segfault only happened when the monitors were aligned in such a way that their top edges were not on the same level. This is usually the case when people were using monitors with different resolutions or one of the monitors in a vertical position.

For example, this setup according to xrandr works (observe that the y offset of both displays ends with +0 for zero vertical offsets):

Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767
DVI-D-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 531mm x 298mm
DP-0 connected 1920x1200+1920+0 (normal left inverted right x axis y axis) 519mm x 324mm

while this setup segfaults (differently sized monitors aligned at their bottom edges in the Linux display settings so the first one has a +120 pixel vertical offset):

Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767
DVI-D-0 connected primary 1920x1080+0+120 (normal left inverted right x axis y axis) 531mm x 298mm
DP-0 connected 1920x1200+1920+0 (normal left inverted right x axis y axis) 519mm x 324mm