diff --git a/nixos/modules/system/boot/stage-1.nix b/nixos/modules/system/boot/stage-1.nix
index 082380216d2a..823969ca4332 100644
--- a/nixos/modules/system/boot/stage-1.nix
+++ b/nixos/modules/system/boot/stage-1.nix
@@ -349,13 +349,7 @@ let
         { object = "${modulesClosure}/lib";
           symlink = "/lib";
         }
-        { object = pkgs.runCommand "initrd-kmod-blacklist-ubuntu" {
-              src = "${pkgs.kmod-blacklist-ubuntu}/modprobe.conf";
-              preferLocalBuild = true;
-            } ''
-              target=$out
-              ${pkgs.buildPackages.perl}/bin/perl -0pe 's/## file: iwlwifi.conf(.+?)##/##/s;' $src > $out
-            '';
+        { object = "${pkgs.kmod-blacklist-ubuntu}/modprobe.conf";
           symlink = "/etc/modprobe.d/ubuntu.conf";
         }
         { object = config.environment.etc."modprobe.d/nixos.conf".source;
diff --git a/nixos/modules/system/boot/systemd/initrd.nix b/nixos/modules/system/boot/systemd/initrd.nix
index eb3b78a14397..597770142f90 100644
--- a/nixos/modules/system/boot/systemd/initrd.nix
+++ b/nixos/modules/system/boot/systemd/initrd.nix
@@ -448,12 +448,7 @@ in {
 
         "/etc/sysctl.d/nixos.conf".text = "kernel.modprobe = /sbin/modprobe";
         "/etc/modprobe.d/systemd.conf".source = "${cfg.package}/lib/modprobe.d/systemd.conf";
-        "/etc/modprobe.d/ubuntu.conf".source = pkgs.runCommand "initrd-kmod-blacklist-ubuntu" {
-            src = "${pkgs.kmod-blacklist-ubuntu}/modprobe.conf";
-            preferLocalBuild = true;
-        } ''
-          ${pkgs.buildPackages.perl}/bin/perl -0pe 's/## file: iwlwifi.conf(.+?)##/##/s;' $src > $out
-        '';
+        "/etc/modprobe.d/ubuntu.conf".source = "${pkgs.kmod-blacklist-ubuntu}/modprobe.conf";
         "/etc/modprobe.d/debian.conf".source = pkgs.kmod-debian-aliases;
 
         "/etc/os-release".source = config.boot.initrd.osRelease;