Threaded scenegraph crash with Nvidia drivers in wayland

Launching another qmlruntime process inside qt wayland compositor causes the compositor process to crash.

When the compositor is set to QSG_RENDER_LOOP=threaded

Note that:

Basic loop works fine though, but as far as I know in uses cases where GUI thread is heavy it will have lower performance for animations.

This is experienced on Ubuntu 17 with Nvidia drivers: 384.69

and also nvidia tegra jetson tx2 where drivers used from here: https://developer.nvidia.com/embedded/linux-tegra

qt is built from sources for branch 5.9 with the following commit hash:

a3f4bf703b9d76b6aa8224240a017d006237f85b

QMake version 3.1
Using Qt version 5.9.2

Tested with the following example:

qt5/qtwayland/examples/wayland/minimal-qml

• Compositor Process has been run under gdb to be able to extract backtrace with the following command:

LD_LIBRARY_PATH=/usr/lib/nvidia-384 QSG_RENDER_LOOP=threaded QSG_INFO=1 /usr/bin/gdb ./minimal-qml 

• qml application has been run with the following command:

LD_LIBRARY_PATH=/usr/lib/nvidia-384 /home/bassem/Dev/qt5/build/qtbase/bin/qmlscene SimpleRect.qml -platform wayland

SimpleRect.qml

Logs from GDB

qtwaylandcrashlogs.txt