Merge pull request #107382 from rnhmjoj/no-udev-settle

nixos/{networkd,dhcpcd}: remove udev-settle hack

nixos/modules/system/boot/networkd.nix

@@ -1553,9 +1553,6 @@ in
         wantedBy = [ "multi-user.target" ];
         aliases = [ "dbus-org.freedesktop.network1.service" ];
         restartTriggers = map (x: x.source) (attrValues unitFiles);
-        # prevent race condition with interface renaming (#39069)
-        requires = [ "systemd-udev-settle.service" ];
-        after = [ "systemd-udev-settle.service" ];
       };
 
       systemd.services.systemd-networkd-wait-online = {

nixos/modules/system/boot/stage-1.nix

@@ -205,13 +205,22 @@ let
     ''; # */
 
 
+  # Networkd link files are used early by udev to set up interfaces early.
+  # This must be done in stage 1 to avoid race conditions between udev and
+  # network daemons.
   linkUnits = pkgs.runCommand "link-units" {
       allowedReferences = [ extraUtils ];
       preferLocalBuild = true;
-    } ''
+    } (''
       mkdir -p $out
       cp -v ${udev}/lib/systemd/network/*.link $out/
-    '';
+      '' + (
+      let
+        links = filterAttrs (n: v: hasSuffix ".link" n) config.systemd.network.units;
+        files = mapAttrsToList (n: v: "${v.unit}/${n}") links;
+      in
+        concatMapStringsSep "\n" (file: "cp -v ${file} $out/") files
+      ));
 
   udevRules = pkgs.runCommand "udev-rules" {
       allowedReferences = [ extraUtils ];