diff --git a/sys/amd64/amd64/genassym.c b/sys/amd64/amd64/genassym.c
--- a/sys/amd64/amd64/genassym.c
+++ b/sys/amd64/amd64/genassym.c
@@ -116,6 +116,7 @@
 ASSYM(KERNLOAD, KERNLOAD);
 ASSYM(DMAP_MIN_ADDRESS, DMAP_MIN_ADDRESS);
 ASSYM(DMAP_MAX_ADDRESS, DMAP_MAX_ADDRESS);
+ASSYM(KSTACK_PAGES, KSTACK_PAGES);
 
 ASSYM(PCB_R15, offsetof(struct pcb, pcb_r15));
 ASSYM(PCB_R14, offsetof(struct pcb, pcb_r14));
diff --git a/sys/amd64/amd64/locore.S b/sys/amd64/amd64/locore.S
--- a/sys/amd64/amd64/locore.S
+++ b/sys/amd64/amd64/locore.S
@@ -48,7 +48,7 @@
 	.set	dmapbase,DMAP_MIN_ADDRESS
 	.set	dmapend,DMAP_MAX_ADDRESS
 
-#define	BOOTSTACK_SIZE	4096
+#define	BOOTSTACK_SIZE	(PAGE_SIZE * KSTACK_PAGES)
 
 	.text
 /**********************************************************************
@@ -148,7 +148,7 @@
 ENTRY(la57_trampoline_end)
 
 	.bss
-	ALIGN_DATA			/* just to be sure */
+	.p2align PAGE_SHIFT
 	.globl	bootstack
 	.space	BOOTSTACK_SIZE		/* space for bootstack - temporary stack */
 bootstack: