[NixOS] A few more cdi/k3s fixes

nixos/k3s.nix

@@ -49,6 +49,28 @@ in {
       };
     };
 
+    systemd.services = {
+      nvidia-container-toolkit-cdi-generator = {
+        # Even with `--library-search-path`, `nvidia-ctk` won't find the libs
+        # unless I bodge their path into the environment.
+        environment.LD_LIBRARY_PATH = "${config.hardware.nvidia.package}/lib";
+      };
+      # k3s-containerd-setup = {
+      #     # `virtualisation.containerd.settings` has no effect on k3s' bundled containerd.
+      #     serviceConfig.Type = "oneshot";
+      #     requiredBy = ["k3s.service"];
+      #     before = ["k3s.service"];
+      #     script = ''
+      #       cat << EOF > /var/lib/rancher/k3s/agent/etc/containerd/config.toml.tmpl
+      #       {{ template "base" . }}
+
+      #       [plugins]
+      #       "io.containerd.grpc.v1.cri".enable_cdi = true
+      #       EOF
+      #     '';
+      # };
+    };
+
     systemd.services.mount-railbird-bucket = {
       after = ["agenix.service"];
       wantedBy = [ "multi-user.target" ];
@@ -113,6 +135,7 @@ in {
 
         [plugins]
         "io.containerd.grpc.v1.cri".enable_cdi = true
+        "io.containerd.grpc.v1.cri".cdi_spec_dirs = [ "/var/run/cdi" ]
       '';
       gracefulNodeShutdown = {
         enable = true;