diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3022dd0..3a062d4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.15)
-project(vxBoot VERSION 1.2.4 LANGUAGES C)
+project(vxBoot VERSION 1.2.5 LANGUAGES C)
 
 include(GenerateG1A)
 include(GenerateG3A)
diff --git a/include/vxBoot/hardware.h b/include/vxBoot/hardware.h
index aa71c09..047e362 100644
--- a/include/vxBoot/hardware.h
+++ b/include/vxBoot/hardware.h
@@ -24,5 +24,7 @@ struct hwinfo {
 /* hardware_get_info() : get hardware information */
 extern int hardware_get_info(struct hwinfo * const hwinfo);
 
+/* hardware_utlb_patch() : patch the UTLB NULL page set by Casio */
+extern void hardware_utlb_patch(void);
 
 #endif /*__VXBOOT_HARDWARE_H__*/
diff --git a/src/builtin/hw.c b/src/builtin/hw.c
index 742c0e3..dc0bff2 100644
--- a/src/builtin/hw.c
+++ b/src/builtin/hw.c
@@ -2,6 +2,7 @@
 #include "vxBoot/terminal.h"
 #include "vxBoot/hardware.h"
 
+#include <string.h>
 
 /* hw_main() : hw builtin entry */
 int hw_main(int argc, char **argv)
@@ -12,6 +13,19 @@ int hw_main(int argc, char **argv)
 	(void)argc;
 	(void)argv;
 
+#ifdef FXCG50
+	if (argc >= 1) {
+		if (strcmp(argv[1], "patch") == 0) {
+			terminal_write("try to invalidate the NULL page...");
+			hardware_utlb_patch();
+			terminal_write("OK\n");
+			return (0);
+		}
+		terminal_write("invalide argument\n");
+		return (84);
+	}
+#endif
+
 	hardware_get_info(&hwinfo);
 	terminal_write(
 		"- user   RAM physical addr: %p\n"
diff --git a/src/hardware/get_info.c b/src/hardware/get_info.c
index a602ad9..606b213 100644
--- a/src/hardware/get_info.c
+++ b/src/hardware/get_info.c
@@ -37,3 +37,21 @@ int hardware_get_info(struct hwinfo * const hwinfo)
 	hwinfo->ram.available -= hwinfo->ram.physical.kernel_addr & 0x00ffffff;
 	return (0);
 }
+
+
+/* hardware_utlb_patch() : patch the UTLB NULL page set by Casio */
+void hardware_utlb_patch(void)
+{
+	for (int i = 0; i < 64; ++i) {
+		utlb_addr_t *addr = (void*)utlb_addr(i);
+		utlb_data_t *data = (void*)utlb_data(i);
+		if(!addr->V || !data->V) continue;
+
+		uintptr_t vaddr = addr->VPN << 10;
+		if (vaddr == 0x00000000) {
+			addr->V = 0;
+			data->V = 0;
+			return;
+		}
+	}
+}
diff --git a/src/loader/entry.c b/src/loader/entry.c
index 658d411..f20a943 100644
--- a/src/loader/entry.c
+++ b/src/loader/entry.c
@@ -61,9 +61,12 @@ int loader(struct smemfs_inode const * restrict const inode, int mode)
 	terminal_write("> relocalize symbols...\n");
 	loader_rela_patch(&kernel);
 
-	terminal_write("> path the GOT table...\n");
+	terminal_write("> patch the GOT table...\n");
 	loader_got_patch(&kernel);
 
+	terminal_write("> patch the UTLB...\n");
+	hardware_utlb_patch();
+
 	terminal_write("%s successfully loaded !\n", inode->name);
 	if (mode == LOADER_DUMP || mode == LOADER_CHECK) {
 		terminal_write(