diff --git a/target/linux/kirkwood/base-files/etc/board.d/05_compat-version b/target/linux/kirkwood/base-files/etc/board.d/05_compat-version
new file mode 100644
index 0000000000..c6026c481f
--- /dev/null
+++ b/target/linux/kirkwood/base-files/etc/board.d/05_compat-version
@@ -0,0 +1,20 @@
+#
+# Copyright (C) 2020 OpenWrt.org
+#
+
+. /lib/functions.sh
+. /lib/functions/uci-defaults.sh
+
+board_config_update
+
+case "$(board_name)" in
+	linksys,e4200-v2|\
+	linksys,ea3500|\
+	linksys,ea4500)
+		ucidef_set_compat_version "2.0"
+		;;
+esac
+
+board_config_flush
+
+exit 0
diff --git a/target/linux/kirkwood/files/arch/arm/boot/dts/kirkwood-ea3500.dts b/target/linux/kirkwood/files/arch/arm/boot/dts/kirkwood-ea3500.dts
index b41243d8dd..f8f940dfc6 100644
--- a/target/linux/kirkwood/files/arch/arm/boot/dts/kirkwood-ea3500.dts
+++ b/target/linux/kirkwood/files/arch/arm/boot/dts/kirkwood-ea3500.dts
@@ -165,22 +165,22 @@
 
 		partition@200000 {
 			label = "kernel1";
-			reg = <0x200000 0x290000>;
+			reg = <0x200000 0x1400000>;
 		};
 
-		partition@490000 {
+		partition@500000 {
 			label = "rootfs1";
-			reg = <0x490000 0x1170000>;
+			reg = <0x500000 0x1100000>;
 		};
 
 		partition@1600000 {
 			label = "kernel2";
-			reg = <0x1600000 0x290000>;
+			reg = <0x1600000 0x1400000>;
 		};
 
-		partition@1890000 {
+		partition@1900000 {
 			label = "rootfs2";
-			reg = <0x1890000 0x1170000>;
+			reg = <0x1900000 0x1100000>;
 		};
 
 		partition@2a00000 {
diff --git a/target/linux/kirkwood/image/Makefile b/target/linux/kirkwood/image/Makefile
index 23d932062e..f1cd2611d2 100644
--- a/target/linux/kirkwood/image/Makefile
+++ b/target/linux/kirkwood/image/Makefile
@@ -7,6 +7,14 @@ include $(INCLUDE_DIR)/image.mk
 
 KERNEL_LOADADDR:=0x8000
 
+define Device/kernel-size-migration
+  DEVICE_COMPAT_VERSION := 2.0
+  DEVICE_COMPAT_MESSAGE := Partition design has changed compared to \
+	older versions (up to 21.02) due to kernel size restrictions. \
+	Upgrade via sysupgrade mechanism is not possible, so new \
+	installation via factory style image is required.
+endef
+
 define Device/Default
   PROFILES := Default
   DEVICE_DTS = kirkwood-$(lastword $(subst _, ,$(1)))
@@ -105,28 +113,31 @@ endef
 
 define Device/linksys_e4200-v2
   $(Device/linksys)
+  $(Device/kernel-size-migration)
   DEVICE_MODEL := E4200
   DEVICE_VARIANT := v2
-  KERNEL_SIZE := 2688k
+  KERNEL_SIZE := 3072k
   SUPPORTED_DEVICES += linksys,viper linksys-viper
 endef
 TARGET_DEVICES += linksys_e4200-v2
 
 define Device/linksys_ea3500
   $(Device/linksys)
+  $(Device/kernel-size-migration)
   DEVICE_MODEL := EA3500
   PAGESIZE := 512
   SUBPAGESIZE := 256
   BLOCKSIZE := 16k
-  KERNEL_SIZE := 2624k
+  KERNEL_SIZE := 3072k
   SUPPORTED_DEVICES += linksys,audi linksys-audi
 endef
 TARGET_DEVICES += linksys_ea3500
 
 define Device/linksys_ea4500
   $(Device/linksys)
+  $(Device/kernel-size-migration)
   DEVICE_MODEL := EA4500
-  KERNEL_SIZE := 2688k
+  KERNEL_SIZE := 3072k
   SUPPORTED_DEVICES += linksys,viper linksys-viper
 endef
 TARGET_DEVICES += linksys_ea4500
diff --git a/target/linux/kirkwood/patches-5.10/105-linksys-viper-dts.patch b/target/linux/kirkwood/patches-5.10/105-linksys-viper-dts.patch
index 0d97ad14a2..d56a469d94 100644
--- a/target/linux/kirkwood/patches-5.10/105-linksys-viper-dts.patch
+++ b/target/linux/kirkwood/patches-5.10/105-linksys-viper-dts.patch
@@ -23,30 +23,37 @@
  		};
  
  		white-pulse {
-@@ -114,22 +119,22 @@
+@@ -114,23 +119,23 @@
  		};
  
  		partition@200000 {
 -			label = "kernel";
+-			reg = <0x200000 0x2A0000>;
 +			label = "kernel1";
- 			reg = <0x200000 0x2A0000>;
++			reg = <0x200000 0x1A00000>;
  		};
  
- 		partition@4a0000 {
+-		partition@4a0000 {
 -			label = "rootfs";
+-			reg = <0x4A0000 0x1760000>;
++		partition@500000 {
 +			label = "rootfs1";
- 			reg = <0x4A0000 0x1760000>;
++			reg = <0x500000 0x1700000>;
  		};
  
  		partition@1c00000 {
 -			label = "alt_kernel";
+-			reg = <0x1C00000 0x2A0000>;
 +			label = "kernel2";
- 			reg = <0x1C00000 0x2A0000>;
++			reg = <0x1C00000 0x1A00000>;
  		};
  
- 		partition@1ea0000 {
+-		partition@1ea0000 {
 -			label = "alt_rootfs";
+-			reg = <0x1EA0000 0x1760000>;
++		partition@1f00000 {
 +			label = "rootfs2";
- 			reg = <0x1EA0000 0x1760000>;
++			reg = <0x1F00000 0x1700000>;
  		};
  
+ 		partition@3600000 {
diff --git a/target/linux/kirkwood/patches-5.4/105-linksys-viper-dts.patch b/target/linux/kirkwood/patches-5.4/105-linksys-viper-dts.patch
index 0d97ad14a2..d56a469d94 100644
--- a/target/linux/kirkwood/patches-5.4/105-linksys-viper-dts.patch
+++ b/target/linux/kirkwood/patches-5.4/105-linksys-viper-dts.patch
@@ -23,30 +23,37 @@
  		};
  
  		white-pulse {
-@@ -114,22 +119,22 @@
+@@ -114,23 +119,23 @@
  		};
  
  		partition@200000 {
 -			label = "kernel";
+-			reg = <0x200000 0x2A0000>;
 +			label = "kernel1";
- 			reg = <0x200000 0x2A0000>;
++			reg = <0x200000 0x1A00000>;
  		};
  
- 		partition@4a0000 {
+-		partition@4a0000 {
 -			label = "rootfs";
+-			reg = <0x4A0000 0x1760000>;
++		partition@500000 {
 +			label = "rootfs1";
- 			reg = <0x4A0000 0x1760000>;
++			reg = <0x500000 0x1700000>;
  		};
  
  		partition@1c00000 {
 -			label = "alt_kernel";
+-			reg = <0x1C00000 0x2A0000>;
 +			label = "kernel2";
- 			reg = <0x1C00000 0x2A0000>;
++			reg = <0x1C00000 0x1A00000>;
  		};
  
- 		partition@1ea0000 {
+-		partition@1ea0000 {
 -			label = "alt_rootfs";
+-			reg = <0x1EA0000 0x1760000>;
++		partition@1f00000 {
 +			label = "rootfs2";
- 			reg = <0x1EA0000 0x1760000>;
++			reg = <0x1F00000 0x1700000>;
  		};
  
+ 		partition@3600000 {