Running on CPU: libEGL warning: failed to open /dev/dri/renderD128: Permission denied

[MRiabov]

Hello,
I'm running a fairly straightforward scene:

def main():
    """Main function to run the Genesis simulation."""
    # Initialize Genesis
    gs.init(backend=gs.cpu, logging_level='info')
    
    # Create a headless scene
    scene = gs.Scene(
        show_viewer=False,
        renderer=gs.renderers.Rasterizer(),
    )
    
    # Add floor
    floor = scene.add_entity(
        gs.morphs.Plane(),
    )
    
    camera = scene.add_camera(
        res=(1280, 720),
        pos=(3.0, -3.0, 2.5),  # Position the camera to view the scene
        lookat=(1.0, 0.0, 0.5),  # Look at the car
        fov=45,
        GUI=False
    )
    
    # Build the scene
    scene.build()
    
    # Start recording
    output_file = "demo.mp4"
    camera.start_recording()
    print(f"Starting simulation and recording to {output_file}...")
    
    # Run the simulation
    for i in range(300): 
        scene.step()
        camera.render()
    
    # Save the recording
    camera.stop_recording(save_to_filename=output_file, fps=60)
    print(f"Simulation complete. Video saved to {output_file}")

And am getting a crash:

[Genesis] [16:52:56] [INFO] ╭─────────────────────────────────────────────────────────────────────────────────────╮
[Genesis] [16:52:56] [INFO] │┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉ Genesis ┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉│
[Genesis] [16:52:56] [INFO] ╰─────────────────────────────────────────────────────────────────────────────────────╯
[Genesis] [16:52:56] [INFO] Running on [Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz] with backend gs.cpu. Device memory: 7.70 GB.
[Genesis] [16:52:56] [INFO] 🚀 Genesis initialized. 🔖 version: 0.2.1, 🌱 seed: None, 📏 precision: '32', 🐛 debug: False, 🎨 theme: 'dark'.
No protocol specified

No protocol specified

[Genesis] [16:52:57] [INFO] Scene <e53fc3a> created.
[Genesis] [16:52:57] [INFO] Adding <gs.RigidEntity>. idx: 0, uid: <d41ea78>, morph: <gs.morphs.Plane>, material: <gs.materials.Rigid>.
[Genesis] [16:52:57] [INFO] Building scene <e53fc3a>...
[W 05/20/25 16:52:58.776 2532222] [frontend_ir.cpp:begin_frontend_struct_for_on_snode@1678] ti.loop_config(serialize=True) does not have effect on the struct for. The execution order is not guaranteed.
[W 05/20/25 16:53:08.610 2532222] [frontend_ir.cpp:begin_frontend_struct_for_on_snode@1678] ti.loop_config(serialize=True) does not have effect on the struct for. The execution order is not guaranteed.
[Genesis] [16:53:10] [INFO] Compiling simulation kernels...
[Genesis] [16:54:00] [INFO] Building visualizer...
libEGL warning: failed to open /dev/dri/renderD128: Permission denied

libEGL warning: NEEDS EXTENSION: falling back to kms_swrast
Segmentation fault (core dumped)

I see the "NEEDS EXTENSION" below, and I thought it has to do with pip but it isn't.
Genesis docs say that simulation should work on CPU. I thought that it is, is it not? And if something needs to be installed for CPU, perhaps it's worth adding a doc about it?
Thanks.

[duburcqa]

I think mujoco is causing the segfault. Are you using the main branch of Genesis?

[MRiabov]

Basically nothing changed:

/home/mriabov/anaconda3/envs/repairs/bin/python /home/mriabov/Work/Projects/Repairs-v0/world_demo.py
No protocol specified

No protocol specified

[Genesis] [18:23:46] [INFO] ╭─────────────────────────────────────────────────────────────────────────────────────╮
[Genesis] [18:23:46] [INFO] │┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉ Genesis ┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉┈┉│
[Genesis] [18:23:46] [INFO] ╰─────────────────────────────────────────────────────────────────────────────────────╯
[Genesis] [18:23:46] [INFO] Running on [Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz] with backend gs.cpu. Device memory: 7.70 GB.
[Genesis] [18:23:46] [DEBUG] [Taichi] version 1.7.3, llvm 15.0.4, commit 5ec301be, linux, python 3.10.17
[Genesis] [18:23:46] [DEBUG] [Taichi] Starting on arch=x64
[Genesis] [18:23:46] [INFO] 🚀 Genesis initialized. 🔖 version: 0.2.1, 🌱 seed: None, 📏 precision: '32', 🐛 debug: False, 🎨 theme: 'dark'.
No protocol specified

No protocol specified

[Genesis] [18:23:47] [INFO] Scene <d5bb51c> created.
[Genesis] [18:23:47] [INFO] Adding <gs.RigidEntity>. idx: 0, uid: <c41d55e>, morph: <gs.morphs.Plane>, material: <gs.materials.Rigid>.
[Genesis] [18:23:47] [DEBUG] Preprocessed `.gsd` file found in cache for geom idx 0.
[Genesis] [18:23:47] [INFO] Building scene <d5bb51c>...
[W 05/21/25 18:23:48.378 2664658] [frontend_ir.cpp:begin_frontend_struct_for_on_snode@1678] ti.loop_config(serialize=True) does not have effect on the struct for. The execution order is not guaranteed.
[W 05/21/25 18:24:01.055 2664658] [frontend_ir.cpp:begin_frontend_struct_for_on_snode@1678] ti.loop_config(serialize=True) does not have effect on the struct for. The execution order is not guaranteed.
[Genesis] [18:24:01] [INFO] Compiling simulation kernels...
[Genesis] [18:24:51] [INFO] Building visualizer...
libEGL warning: failed to open /dev/dri/renderD128: Permission denied

libEGL warning: NEEDS EXTENSION: falling back to kms_swrast
Segmentation fault (core dumped)

I will meanwhile try to create a new conda env and see whether that works

[duburcqa]

Please have a look to the troubleshooting section of the installation procedure. It looks like some rendering issue:
https://genesis-world.readthedocs.io/en/latest/user_guide/overview/installation.html#troubleshooting

[duburcqa]

Besides, it should could share more information regarding your setup that would be helpful (e.g. OS, CPU, GPU, docker or not, WSL or not...etc, X11 via SSH...etc). I suspect it is related to the failed to open /dev/dri/renderD128: Permission denied warning. It seems that Genesis is having trouble to access to the rendering devices.

[MRiabov]

Hello,
This is a CPU-only laptop (this was in logs in the first comment, by the way), with CPU being i7-7500U, 16gb RAM. Running in WSL2, Linux 22.04.
I did not install the ray-tracing renderer because I expect to not need it (due to being on CPU) - is this the cause? I understand that genesis (should) ship with an in-built renderer.
Not using SSH at the moment.
Installed through `pip install -e ".[render]".
Hmm. Have you tried actually clean installing genesis on CPU-only instances? There could be some minor task that would use GPU but for 0.1 second through the CPU backend.

I could just start rendering on rented GPU instances, but then, the issue will go unresolved (and I'll have to pay royalty for the GPU).

[duburcqa]

Actually the CI is running on Linux, MacOS, and Windows including rendering, on CPU-only. So it is extensively tested, but not WSL2. You should follow the instructions for WLS2 without docker available here:

sudo add-apt-repository ppa:kisak/kisak-mesa
sudo apt update
sudo apt upgrade

export LIBGL_ALWAYS_INDIRECT=0
export LIBGL_ALWAYS_SOFTWARE=1

[MRiabov]

By the way, this was never resolved. Would be good if you add at least minimal WSL tests. Also, the current doc does not explain installation on CPU-based WSL.

Not only that, I can't even import anything that transiently imports genesis (even if not init). E.g., I run a script that uses genesis for typing purposes, but it fails with viewer not found or something similar. I don't think Genesis should block any script if x11 is not started.