diff --git a/boot.asm b/boot.asm
index 7c4c794..664f5e2 100644
--- a/boot.asm
+++ b/boot.asm
@@ -1,3 +1,4 @@
+; c.f. https://www.gnu.org/software/grub/manual/multiboot/multiboot.html#OS-image-format
 ; Declare constants for the multiboot header.
 MBALIGN  equ  1 << 0            ; align loaded modules on page boundaries
 MEMINFO  equ  1 << 1            ; provide memory map
@@ -54,6 +55,7 @@ _start:
 	; stack (as it grows downwards on x86 systems). This is necessarily done
 	; in assembly as languages such as C cannot function without a stack.
 	mov esp, stack_top
+	mov ebp, stack_bottom
  
 	; This is a good place to initialize crucial processor state before the
 	; high-level kernel is entered. It's best to minimize the early
diff --git a/boot.s b/boot.s
index 8aa2a07..2ebf558 100644
--- a/boot.s
+++ b/boot.s
@@ -64,6 +64,7 @@ _start:
 	in assembly as languages such as C cannot function without a stack.
 	*/
 	mov $stack_top, %esp
+	mov $stack_bottom, %ebp
 
 	/*
 	This is a good place to initialize crucial processor state before the