diff --git a/headers/private/kernel/arch/x86/arch_kernel.h b/headers/private/kernel/arch/x86/arch_kernel.h
index 106728c219..c81a29567d 100644
--- a/headers/private/kernel/arch/x86/arch_kernel.h
+++ b/headers/private/kernel/arch/x86/arch_kernel.h
@@ -25,6 +25,6 @@
 #define USER_TOP    (USER_BASE + USER_SIZE)
 
 #define USER_STACK_REGION 0x70000000
-#define USER_STACK_REGION_SIZE (USER_BASE + (USER_SIZE - USER_STACK_REGION))
+#define USER_STACK_REGION_SIZE (USER_TOP - USER_STACK_REGION)
 
 #endif /* _KERNEL_ARCH_x86_KERNEL_H */