App crash: corrupted size vs. prev_size in fastbins

[LeBeef]

Dear community,

I am running a PySide6 app. It has a idle view with a looping video in the background. The application runs 24h a day. 2 or 3 times a day the application crashes without any interaction with the flowing messages:

QML: Error transferring the data to system memory: -5
QML: Cannot map a video frame in ReadOnly mode!
corrupted size vs. prev_size in fastbins

This is the backtrace:

Thread 61 "QSGRenderThread" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fff27fff640 (LWP 8354)]
0x00007ffff66accd1 in __dynamic_cast () from /lib/x86_64-linux-gnu/libstdc++.so.6
(gdb) bt
#0  0x00007ffff66accd1 in __dynamic_cast () from /lib/x86_64-linux-gnu/libstdc++.so.6
#1  0x00007fff4ab23376 in ?? () from /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so
#2  0x00007fff4ab2a241 in ?? () from /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so
#3  0x00007fffa8017e84 in vaSyncSurface () from /lib/x86_64-linux-gnu/libva.so.2
#4  0x00007fff864ace48 in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/plugins/multimedia/libffmpegmediaplugin.so
#5  0x00007fff864ad3aa in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/plugins/multimedia/libffmpegmediaplugin.so
#6  0x00007fff864a8d33 in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/plugins/multimedia/libffmpegmediaplugin.so
#7  0x00007fff864a8dc7 in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/plugins/multimedia/libffmpegmediaplugin.so
#8  0x00007fff8594cfb3 in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/plugins/multimedia/libffmpegmediaplugin.so
#9  0x00007fffc0093149 in QVideoFrame::map(QVideoFrame::MapMode) () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/qml/QtMultimedia/../../lib/libQt6Multimedia.so.6
#10 0x00007fffc00970fc in QVideoTextureHelper::createTextures(QVideoFrame&, QRhi*, QRhiResourceUpdateBatch*, std::unique_ptr<QVideoFrameTextures, std::default_delete<QVideoFrameTextures> >&&) ()
   from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/qml/QtMultimedia/../../lib/libQt6Multimedia.so.6
#11 0x00007fffd0035d78 in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/qml/QtMultimedia/../../lib/libQt6MultimediaQuick.so.6
#12 0x00007fffd0035f1b in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/qml/QtMultimedia/../../lib/libQt6MultimediaQuick.so.6
#13 0x00007fffef6d29fb in QSGBatchRenderer::Renderer::updateMaterialDynamicData(QSGBatchRenderer::ShaderManagerShader*, QSGMaterialShader::RenderState&, QSGMaterial*, QSGBatchRenderer::Batch const*, QSGBatchRenderer::Element*, int, int) () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#14 0x00007fffef6d4d1c in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#15 0x00007fffef6d5cfe in QSGBatchRenderer::Renderer::prepareRenderPass(QSGBatchRenderer::Renderer::RenderPassContext*) ()
   from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#16 0x00007fffef6d7963 in QSGBatchRenderer::Renderer::render() () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#17 0x00007fffef6edc42 in QSGRenderer::renderScene() () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#18 0x00007fffef692d8e in QQuickWindowPrivate::renderSceneGraph() () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#19 0x00007fffef87c03d in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#20 0x00007fffef87d577 in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Quick.so.6
#21 0x00007ffff5afc66d in ?? () from /home/deploy/devel/0095/.venv/lib/python3.12/site-packages/PySide6/Qt/lib/libQt6Core.so.6
#22 0x00007ffff7494ac3 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#23 0x00007ffff7526850 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

Environment:

$ cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04.4 LTS"
(venv) $ python -V
Python 3.12.3
(venv) $ pip list
Package            Version
------------------ --------
annotated-types    0.7.0
certifi            2024.6.2
pip                24.1
pydantic           2.7.4
pydantic_core      2.18.4
PySide6            6.7.2
PySide6_Addons     6.7.2
PySide6_Essentials 6.7.2
sentry-sdk         2.6.0
setuptools         70.1.0
shiboken6          6.7.2
typing_extensions  4.12.2
urllib3            2.2.2

The qml snippet:

Video {
    id: bgVideo
    anchors.fill: parent
    autoPlay: true
    loops: MediaPlayer.Infinite
    source: "idle_animation.mp4"
}

You you have an idea what could cause those crashes?

Kind regards

Nils

[SGaist]

Hi,

Did you try to check system logs to see if there was something wrong going on ?
What about memory used by your application ?

[LeBeef]

Hi @SGaist,

fortunately we are logging all the pc resources, but there was nothing unusual during the crash and nothing unusual in syslog. Another error I saw around the crash is this:

[AVHWFramesContext @ 0x7f7b28051180] Failed to sync surface 0x3f: 1 (operation failed).

[SGaist]

What about dmesg ?

[LeBeef]

@SGaist said in App crash: corrupted size vs. prev_size in fastbins:

dmesg

Unfortunately no messages related to the crashes.

[SGaist]

Strange...
What is your video hardware ?

[LeBeef]

@SGaist We have our app running on two different systems. One has a Nvidia GPU and one has intel graphics. It happens only on the one with intel graphics. Here are the details:

        *-display
             description: VGA compatible controller
             product: Alder Lake-P Integrated Graphics Controller
             vendor: Intel Corporation
             physical id: 2
             bus info: pci@0000:00:02.0
             logical name: /dev/fb0
             version: 0c
             width: 64 bits
             clock: 33MHz
             capabilities: pciexpress msi pm vga_controller bus_master cap_list rom fb
             configuration: depth=32 driver=i915 latency=0 mode=1920x1080 resolution=1920,1080 visual=truecolor xres=1920 yres=1080
             resources: iomemory:600-5ff iomemory:400-3ff irq:165 memory:6000000000-6000ffffff memory:4000000000-400fffffff ioport:3000(size=64) memory:c0000-dffff memory:4010000000-4016ffffff memory:4020000000-40ffffffff

[LeBeef]

PS: It happens on multiple instances of intel, which playback different video files.

[SGaist]

Ok, so at least there's some common point of failure.

Which backend are you using ?

[LeBeef]

@SGaist Since I did not set anything with an ENV var I guess it is using ffmpeg right?

[SGaist]

Since you are using 6.7, that should be the default yes.

You can check that by setting the QT_DEBUG_PLUGINS environment variable to 1 in the terminal where you start your application.