diff --git a/modules/system/activation/top-level.nix b/modules/system/activation/top-level.nix
index aa79fb3698d..265f06a5a9d 100644
--- a/modules/system/activation/top-level.nix
+++ b/modules/system/activation/top-level.nix
@@ -38,9 +38,6 @@ let
       description = ''
         Name of the kernel file to be passed to the bootloader.
       '';
-      merge = kernelFiles:
-        builtins.head (map (f: assert f == builtins.head kernelFiles; f)
-          kernelFiles);
     };
 
     system.copySystemConfiguration = pkgs.lib.mkOption {