pass nvidia gpu to vm

modules/hardware/vfio.nix

@@ -6,9 +6,18 @@ in
 {
   options.custom.hardware.vfio = {
     enable = mkEnableOption "Enables vfio";
+    stub_pci = mkOption {
+      type = with lib.types; listOf str;
+      default = [ ];
+      description = "List of PCI devices to stub with vfio-pci";
+    };
   };
 
   config = mkIf (cfg.enable && config.virtualisation.libvirtd.enable) {
-    boot.kernelParams = [ "amd_iommu=on" "iommu=pt" ];
+    boot = {
+      kernelModules = [ "vfio" "vfio_iommu_type1" "vfio_pci" ];
+      kernelParams = [ "amd_iommu=on" "iommu=pt" ] ++ (if cfg.stub_pci != [] then [ "vfio-pci.ids=${concatStringsSep "," cfg.stub_pci}" ] else []);
+      blacklistedKernelModules = [ "nouveau" "nvidia" "nvidiafb" "nvidia-drm" "nvidia-uvm" "nvidia-modeset" ];
+    };
   };
 }

systems/amd-server/configuration.nix

@@ -1,7 +1,5 @@
-# Edit this configuration file to define what should be installed on
-# your system. Help is available in the configuration.nix(5) man page, on
-# https://search.nixos.org/options and in the NixOS manual (`nixos-help`).
-
+# 0000:2b:00.0 VGA compatible controller [0300]: NVIDIA Corporation GM204 [GeForce GTX 970] [10de:13c2] (rev a1)
+# 0000:2b:00.1 Audio device [0403]: NVIDIA Corporation GM204 High Definition Audio Controller [10de:0fbb] (rev a1)
 { config, lib, pkgs, ... }:
 
 {
@@ -25,9 +23,13 @@
     };
     hardware = {
       #amd-gpu.enable = true;
-      nvidia.enable = true;
+      nvidia.enable = false;
       firmware.enable = true;
       ssd.enable = true;
+      vfio = {
+        enable = true;
+        stub_pci = [ "10de:13c2" "10de:0fbb" ]; #nvidia
+      };
       wooting.enable = true;
     };
     services = {
@@ -40,7 +42,7 @@
     };
     graphical = {
       audio.enable = true;
-      sddm.enable = true;
+      #sddm.enable = true;
       #nightlight.enable = true;
       #i3.enable = true;
       xfce.enable = true;
@@ -54,6 +56,7 @@
   };
   mainUser.layout = "de";
   mainUser.variant = "us";
+  services.xserver.displayManager.lightdm.enable = false; #no login manager!
 
   nix.gc.automatic = lib.mkForce false;
   networking = {