genkernel: use udev instead of mdev by default

gen_determineargs.sh

@@ -111,7 +111,7 @@ determine_real_args() {
     set_config_with_override BOOL   SYMLINK              CMD_SYMLINK
     set_config_with_override STRING INSTALL_MOD_PATH     CMD_INSTALL_MOD_PATH
     set_config_with_override BOOL   OLDCONFIG            CMD_OLDCONFIG
-    set_config_with_override BOOL   UDEV                 CMD_UDEV
+    set_config_with_override BOOL   UDEV                 CMD_UDEV                 "yes"
     set_config_with_override BOOL   LVM                  CMD_LVM
     set_config_with_override BOOL   DMRAID               CMD_DMRAID
     set_config_with_override BOOL   ISCSI                CMD_ISCSI

genkernel.conf

@@ -78,6 +78,10 @@ USECOLOR="yes"
 # If included, busybox is rebuilt if the cached copy is out of date.
 #BUSYBOX="yes"
 
+# Use udev instead of mdev as the default device manager for the initramfs.
+# If you use systemd and perhaps lvm, you _must_ keep this turned on.
+#UDEV="yes"
+
 # Includes mdadm/mdmon binaries in initramfs.
 # Without sys-fs/mdadm[static] installed, this will build a static mdadm.
 #MDADM="no"