error with hardware.nvidia.open (dell xps 15 7590)

[eg-ayoub]

on my xps laptop using this flake:

      # 2 - mouse : (laptop) Tiling WM + dev tools
      mouse = nixpkgs.lib.nixosSystem {
        specialArgs = { inherit inputs system; };

        modules = [
          ./hosts/mouse/configuration.nix
          nixos-hardware.nixosModules.dell-xps-15-7590-nvidia
        ];
      };

in configuration.nix I have:
hardware.nvidia.prime.offload.enable = true;

nixos rebuild fails with

$ sudo nixos-rebuild switch --flake .#mouse --option eval-cache false
warning: Git tree '/home/ayoub/repos/nix-files' is dirty
building the system configuration...
warning: Git tree '/home/ayoub/repos/nix-files' is dirty
error:
       … while calling the 'head' builtin

         at /nix/store/887hpp8a2i99n9jjwcvz6qkhhhqsvzkg-source/lib/attrsets.nix:1575:11:

         1574|         || pred here (elemAt values 1) (head values) then
         1575|           head values
             |           ^
         1576|         else

       … while evaluating the attribute 'value'

         at /nix/store/887hpp8a2i99n9jjwcvz6qkhhhqsvzkg-source/lib/modules.nix:821:9:

          820|     in warnDeprecation opt //
          821|       { value = addErrorContext "while evaluating the option `${showOption loc}':" value;
             |         ^
          822|         inherit (res.defsFinal') highestPrio;

       (stack trace truncated; use '--show-trace' to show the full trace)

       error: The option `hardware.nvidia.open' is used but not defined.

I assumed this option is set automatically by https://github.com/NixOS/nixpkgs/blob/nixos-unstable/pkgs/os-specific/linux/nvidia-x11/default.nix
am I wrong ?
thanks for your help in advance :)

[BCNelson]

It was an intentional breaking change NixOS/nixpkgs#337289 (comment) there will need to be some changes to fix it and figure out if it should be turned on for your gpu

[eg-ayoub]

@BCNelson thanks!
I'll make a PR by tomorrow.
If 560 works on my machine would it be acceptable to set hardware.nvidia.open = true; for xps15-7590 ?

[BCNelson]

I'm not sure about the specifics. But I do know that it defaulted to false before