diff --git a/pkgs/build-support/kernel/make-initrd.nix b/pkgs/build-support/kernel/make-initrd.nix
index 092ab4586b38..70727f9b49dc 100644
--- a/pkgs/build-support/kernel/make-initrd.nix
+++ b/pkgs/build-support/kernel/make-initrd.nix
@@ -12,7 +12,9 @@
 # `contents = {object = ...; symlink = /init;}' is a typical
 # argument.
 
-{ stdenv, perl, cpio, contents, ubootChooser, compressor, prepend }:
+{ stdenv, perl, cpio, contents, ubootChooser, compressor, prepend
+, hostPlatform
+}:
 
 let
   inputsFun = ubootName : [ perl cpio ]
@@ -22,9 +24,9 @@ in
 stdenv.mkDerivation {
   name = "initrd";
   builder = ./make-initrd.sh;
-  nativeBuildInputs = inputsFun stdenv.platform.uboot;
+  nativeBuildInputs = inputsFun hostPlatform.platform.uboot;
 
-  makeUInitrd = makeUInitrdFun stdenv.platform.uboot;
+  makeUInitrd = makeUInitrdFun hostPlatform.platform.uboot;
 
   # !!! should use XML.
   objects = map (x: x.object) contents;
@@ -36,9 +38,5 @@ stdenv.mkDerivation {
     map (x: [("closure-" + baseNameOf x.symlink) x.object]) contents;
   pathsFromGraph = ./paths-from-graph.pl;
 
-  crossAttrs = {
-    nativeBuildInputs = inputsFun stdenv.cross.platform.uboot;
-    makeUInitrd = makeUInitrdFun stdenv.cross.platform.uboot;
-  };
   inherit compressor prepend;
 }