0.1.8 on NixOS crashing the system

[djmaze]

Running NixOS 24.05, I was using niri 0.1.6 from NixOS stable before. Today I tried running 0.1.8 from NixOS unstable – from the tty using exec niri --session, as I was doing before. niri outputs some logs and then there is just a black screen and the system seems to have been totally halted (not even able to switch to a different tty via keyboard). I need to turn the laptop off. The first time after turning it on again, the screen stays black. I need to turn it off a second time until it gets back to life. So it seems something really severe stuff happening there.

I experienced a few kernel panics before with niri, while something like this never happened with Hyprland.

This is on a Thinkpad X1 Yoga 2nd Gen. I did not yet have time to dig deeper yet – that's why I did not open an issue yet. But is anyone else seeing these kinds of crashes?

[YaLTeR]

Black screen usually means that niri failed to initialize the GPU. Though, the rest of the compositor should work, i.e. Mod+Shift+E => Enter should exit it, or, indeed, switching to a different TTY. So that's the weird part that you can't switch to a different TTY.

It can fail to initialize the GPU for example if on NixOS you get a Mesa version mismatch somehow.

Try getting the niri output when it black screens?

[djmaze]

Thanks! I could get out of it using Mod+Shift+E. This is an extract of the log:

did not find extension DRI_Mesa version 2
did not find extension DRI_IMAGE_DRIVER version 2
failed to bind extensions
did not find extension DRI_Mesa version 2
did not find extension DRI_IMAGE_DRIVER version 2
failed to bind extensions
did not find extension DRI_Mesa version 2
did not find extension DRI_SWRast version 5
failed to bind extensions
2024-08-22T20:56:00.794955Z  WARN niri::backend::tty: error adding device: No such file or directory (os error 2)
2024-08-22T20:56:00.794977Z  INFO niri: listening on Wayland socket: wayland-1
2024-08-22T20:56:00.794983Z  INFO niri: IPC listening on: /run/user/1000/niri.wayland-1.46999.sock
2024-08-22T20:56:02.832390Z  WARN niri::backend::tty: error doing early import: Error::DeviceMissing
2024-08-22T20:56:02.832467Z  WARN niri::backend::tty: error doing early import: Error::DeviceMissing

So it seems indeed Mesa-related. Maybe it is a problem as I am mixing in this unstable package into my stable NixOS?

[djmaze]

So how can I find out niri's Mesa version?

[YaLTeR]

@sodiboo hey, do you know how to check this?

[sodiboo]

something like nix-store -qR $(dirname $(dirname $(readlink $(which niri)))) | rg mesa should give you the mesa version.

to make it build with the correct mesa version, consider something like pkgs-unstable.niri.override { inherit (pkgs-stable) mesa; }.

consider also using niri-flake's niri-stable package from its overlay, which should be 0.1.8 and build against the correct version of mesa.

I'd love to elaborate a little more later, but right now I'm sorta busy