diff --git a/Kernel/init.cpp b/Kernel/init.cpp
index e37f5a6a26..9530ec5c4a 100644
--- a/Kernel/init.cpp
+++ b/Kernel/init.cpp
@@ -107,9 +107,9 @@ static Processor s_bsp_processor; // global but let's keep it "private"
 // init_stage2() function. Initialization continues there.
 
 extern "C" {
-PhysicalAddress start_of_prekernel_image;
-PhysicalAddress end_of_prekernel_image;
-FlatPtr kernel_base;
+READONLY_AFTER_INIT PhysicalAddress start_of_prekernel_image;
+READONLY_AFTER_INIT PhysicalAddress end_of_prekernel_image;
+READONLY_AFTER_INIT FlatPtr kernel_base;
 #if ARCH(X86_64)
 PhysicalAddress boot_pml4t;
 #endif