anchor.diff:  
               # x86 RTC needed by the stage 2 init script.
               "rtc_cmos"
  -          ];
  +          ]);
   
           boot.initrd.kernelModules =
  -          [ # For LVM.
  +          optionals config.boot.initrd.includeDefaultModules [
  +            # For LVM.
               "dm_mod"
             ];
         })
  
positive.code:   config = mkMerge
      [ (mkIf config.boot.initrd.enable {
          boot.initrd.availableKernelModules =
            [ # Note: most of these (especially the SATA/PATA modules)
              # shouldn't be included by default since nixos-generate-config
              # detects them, but I'm keeping them for now for backwards
              # compatibility.
  
negative.code:       description = "List of modules that are always loaded by the initrd.";
      };
  
      boot.initrd.includeDefaultModules = mkOption {
        type = types.bool;
        default = true;
        description = ''
          This option, if set, adds a collection of default kernel modules
          to <option>boot.initrd.availableKernelModules</option> and
          <option>boot.initrd.kernelModules</option>.
        '';
      };
  
      system.modulesTree = mkOption {
        type = types.listOf types.path;
        internal = true;
  