diff --git a/pkgs/os-specific/linux/kernel/manual-config.nix b/pkgs/os-specific/linux/kernel/manual-config.nix
index 34bcaba3f31..131ff74bcf1 100644
--- a/pkgs/os-specific/linux/kernel/manual-config.nix
+++ b/pkgs/os-specific/linux/kernel/manual-config.nix
@@ -82,7 +82,7 @@ stdenv.mkDerivation ({
     runHook postInstall
   '';
 } // optionalAttrs features.modular {
-  MODLIB = "$(out)/lib/modules/${modDirVersion}";
+  makeFlags = [ "MODLIB=\"$(out)/lib/modules/${modDirVersion}\"" ];
 
   INSTALL_MOD_STRIP = "1";