diff --git a/sys/amd64/include/pmap.h b/sys/amd64/include/pmap.h
--- a/sys/amd64/include/pmap.h
+++ b/sys/amd64/include/pmap.h
@@ -495,7 +495,6 @@
 vm_page_t pmap_page_alloc_below_4g(bool zeroed);
 
 #if defined(KASAN) || defined(KMSAN)
-void	pmap_san_bootstrap(void);
 void	pmap_san_enter(vm_offset_t);
 #endif
 
diff --git a/sys/arm64/arm64/locore.S b/sys/arm64/arm64/locore.S
--- a/sys/arm64/arm64/locore.S
+++ b/sys/arm64/arm64/locore.S
@@ -45,6 +45,11 @@
 #define	L3_PAGE_COUNT	32
 #endif
 
+/*
+ * The size of our bootstrap stack.
+ */
+#define	BOOT_STACK_SIZE	(KSTACK_PAGES * PAGE_SIZE)
+
 	.globl	kernbase
 	.set	kernbase, KERNBASE
 
@@ -147,7 +152,9 @@
 	mov	x19, x0
 
 	/* Bootstrap an early shadow map for the boot stack. */
-	bl	pmap_san_bootstrap
+	ldr	x0, [x0, #BP_KERN_STACK]
+	ldr	x1, =BOOT_STACK_SIZE
+	bl	kasan_init_early
 
 	/* Restore bootparams */
 	mov	x0, x19
@@ -880,7 +887,7 @@
 .bss
 	.align	PAGE_SHIFT
 initstack:
-	.space	(PAGE_SIZE * KSTACK_PAGES)
+	.space	BOOT_STACK_SIZE
 initstack_end:
 
 	.section .init_pagetable, "aw", %nobits
diff --git a/sys/arm64/arm64/pmap.c b/sys/arm64/arm64/pmap.c
--- a/sys/arm64/arm64/pmap.c
+++ b/sys/arm64/arm64/pmap.c
@@ -7864,12 +7864,6 @@
 #if defined(KASAN)
 static pd_entry_t	*pmap_san_early_l2;
 
-void __nosanitizeaddress
-pmap_san_bootstrap(struct arm64_bootparams *abp)
-{
-	kasan_init_early(abp->kern_stack, KSTACK_PAGES * PAGE_SIZE);
-}
-
 #define	SAN_BOOTSTRAP_L2_SIZE	(1 * L2_SIZE)
 #define	SAN_BOOTSTRAP_SIZE	(2 * PAGE_SIZE)
 static vm_offset_t __nosanitizeaddress
diff --git a/sys/arm64/include/pmap.h b/sys/arm64/include/pmap.h
--- a/sys/arm64/include/pmap.h
+++ b/sys/arm64/include/pmap.h
@@ -194,7 +194,6 @@
 
 void	pmap_bootstrap_san(void);
 void	pmap_san_enter(vm_offset_t);
-void	pmap_san_bootstrap(struct arm64_bootparams *);
 #endif
 
 #endif	/* _KERNEL */