New NixOS Module is broken. Permissions denied

[leifhelm]

Hey,

I tried the new kmonad module and the service is not starting.

This is the log from systemctl

Mai 23 13:51:22 desktop systemd[1]: Started KMonad for /dev/input/by-id/usb-Razer_Razer_Huntsman_Elite-if01-event-kbd.
Mai 23 13:51:22 desktop kmonad-razer-huntsman-start[1502]: kmonad: /dev/input/by-id/usb-Razer_Razer_Huntsman_Elite-if01-event-kbd: openFd: permission denied (Permission denied)
Mai 23 13:51:22 desktop systemd[1]: kmonad-razer-huntsman.service: Main process exited, code=exited, status=1/FAILURE

And this is my configuration

{
  services.kmonad = {
    enable = true;
    keyboards = {
      razer-huntsman = {
        device = "/dev/input/by-id/usb-Razer_Razer_Huntsman_Elite-if01-event-kbd";
        fallthrough = true;
        allowCommands = false;
        config = builtins.readFile ./keyboard.kbd;
      };
    };
  };
}

I removed defcfg portion in the keyboard.kbd file

@pjones have I misconfigured the module? Am I missing an option?

BR

[pjones]

@leifhelm Can you tell me the group of that device file? It should be uinput as assigned by the udev rule.

[leifhelm]

ls -l /dev/input/by-id/usb-Razer_Razer_Huntsman_Elite-if01-event-kbd
lrwxrwxrwx 1 root root 9 23. Mai 23:25 /dev/input/by-id/usb-Razer_Razer_Huntsman_Elite-if01-event-kbd -> ../event3

And

ls -l /dev/uinput
crw-rw---- 1 root uinput 10, 223 23. Mai 23:25 /dev/uinput

I hope that is what you asked for

[pjones]

@leifhelm Have you disconnected your keyboard (and then reconnected) or rebooted since upgrading to the latest NixOS module? I bet that the new udev rule hasn't run for that device, but if you disconnect and reconnect it will.

[leifhelm]

I have had rebooted my system

[pjones]

Can you show me the ownership and group information for /dev/input/event3?

I'm expecting the owner to be root, the group to be input and the mode to be 660 (rw-rw----). The kmonad service runs with the ability to read files that are in the input and uinput groups. So if your permissions aren't what I'm expecting we'll need to figure out why.

[leifhelm]

It is actually openrazer

ls -l /dev/input/event3
crw-rw---- 1 root openrazer 13, 67 24. Mai 12:21 /dev/input/event3

I am running the openrazer daemon to control the RGB on my keyboard.
When adding

{
  users.users.kmonad.extraGroups = [ "openrazer" ];
}

it works fine.
My user account is also in the openrazer group.

[pjones]

Okay, that makes sense then.

Perhaps we should add an option to the NixOS module to make it easier to add more groups. I'll work something up.

Thanks for working with me on this.