diff --git a/sys/alpha/alpha/machdep.c b/sys/alpha/alpha/machdep.c
index 931e24e11848..eecd53f97d7d 100644
--- a/sys/alpha/alpha/machdep.c
+++ b/sys/alpha/alpha/machdep.c
@@ -92,6 +92,7 @@ __FBSDID("$FreeBSD$");
 
 #include "opt_compat.h"
 #include "opt_ddb.h"
+#include "opt_kstack_pages.h"
 #include "opt_msgbuf.h"
 #include "opt_maxmem.h"
 
diff --git a/sys/alpha/alpha/mp_machdep.c b/sys/alpha/alpha/mp_machdep.c
index f37d0f143af9..78f9c8668eb7 100644
--- a/sys/alpha/alpha/mp_machdep.c
+++ b/sys/alpha/alpha/mp_machdep.c
@@ -27,6 +27,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/ktr.h>
diff --git a/sys/alpha/alpha/vm_machdep.c b/sys/alpha/alpha/vm_machdep.c
index cd0a1b7ae8db..dfac21713124 100644
--- a/sys/alpha/alpha/vm_machdep.c
+++ b/sys/alpha/alpha/vm_machdep.c
@@ -69,6 +69,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
diff --git a/sys/alpha/include/param.h b/sys/alpha/include/param.h
index 60957140a890..324219bb627b 100644
--- a/sys/alpha/include/param.h
+++ b/sys/alpha/include/param.h
@@ -117,7 +117,9 @@
 #define	SSIZE		1		/* initial stack size/NBPG */
 #define	SINCR		1		/* increment of stack/NBPG */
 
+#ifndef	KSTACK_PAGES
 #define	KSTACK_PAGES	2		/* pages of kstack (with pcb) */
+#endif
 #define	KSTACK_GUARD_PAGES	1	/* pages of kstack guard; 0 disables */
 #define	UAREA_PAGES	1		/* pages of u-area */
 
diff --git a/sys/ia64/ia64/mp_machdep.c b/sys/ia64/ia64/mp_machdep.c
index f06e0cc1c3c3..1284e8ee2a15 100644
--- a/sys/ia64/ia64/mp_machdep.c
+++ b/sys/ia64/ia64/mp_machdep.c
@@ -26,6 +26,8 @@
  *	$FreeBSD$
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/ktr.h>
diff --git a/sys/ia64/ia64/vm_machdep.c b/sys/ia64/ia64/vm_machdep.c
index 2aa78fdedd22..b8aa99accc25 100644
--- a/sys/ia64/ia64/vm_machdep.c
+++ b/sys/ia64/ia64/vm_machdep.c
@@ -67,6 +67,8 @@
  * rights to redistribute these changes.
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
diff --git a/sys/ia64/include/param.h b/sys/ia64/include/param.h
index 1b3bf0c6d33e..c0d18a4c9191 100644
--- a/sys/ia64/include/param.h
+++ b/sys/ia64/include/param.h
@@ -134,7 +134,9 @@
 #define	SSIZE		1		/* initial stack size/NBPG */
 #define	SINCR		1		/* increment of stack/NBPG */
 
+#ifndef	KSTACK_PAGES
 #define	KSTACK_PAGES	4		/* pages of kernel stack */
+#endif
 #define	KSTACK_GUARD_PAGES 0		/* pages of kstack guard; 0 disables */
 #define	UAREA_PAGES	1		/* pages of u-area */
 
diff --git a/sys/powerpc/aim/machdep.c b/sys/powerpc/aim/machdep.c
index ddc26705b644..ce2f85c55bd3 100644
--- a/sys/powerpc/aim/machdep.c
+++ b/sys/powerpc/aim/machdep.c
@@ -59,6 +59,7 @@ __FBSDID("$FreeBSD$");
 
 #include "opt_ddb.h"
 #include "opt_compat.h"
+#include "opt_kstack_pages.h"
 #include "opt_msgbuf.h"
 
 #include <sys/param.h>
diff --git a/sys/powerpc/aim/mmu_oea.c b/sys/powerpc/aim/mmu_oea.c
index 0ef6e0d4304a..4ca3a98dc2a8 100644
--- a/sys/powerpc/aim/mmu_oea.c
+++ b/sys/powerpc/aim/mmu_oea.c
@@ -114,6 +114,8 @@ __FBSDID("$FreeBSD$");
  * correct.
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/ktr.h>
diff --git a/sys/powerpc/aim/vm_machdep.c b/sys/powerpc/aim/vm_machdep.c
index b9aa06b640c5..b067b321698f 100644
--- a/sys/powerpc/aim/vm_machdep.c
+++ b/sys/powerpc/aim/vm_machdep.c
@@ -67,6 +67,8 @@
  * rights to redistribute these changes.
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
diff --git a/sys/powerpc/include/param.h b/sys/powerpc/include/param.h
index cf4d4a49e77d..19494f9d64f9 100644
--- a/sys/powerpc/include/param.h
+++ b/sys/powerpc/include/param.h
@@ -97,10 +97,10 @@
 #define	KERNBASE	0x100000	/* start of kernel virtual */
 #define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
 
-#ifndef KSTACK_UPAGES
+#ifndef KSTACK_PAGES
 #define	KSTACK_PAGES		4		/* includes pcb */
-#define	KSTACK_GUARD_PAGES	1	/* pages of kstack guard; 0 disables */
 #endif
+#define	KSTACK_GUARD_PAGES	1	/* pages of kstack guard; 0 disables */
 #define	USPACE		(KSTACK_PAGES * PAGE_SIZE)	/* total size of pcb */
 #define	UAREA_PAGES	1		/* holds struct user WITHOUT PCB */
 
diff --git a/sys/powerpc/powerpc/machdep.c b/sys/powerpc/powerpc/machdep.c
index ddc26705b644..ce2f85c55bd3 100644
--- a/sys/powerpc/powerpc/machdep.c
+++ b/sys/powerpc/powerpc/machdep.c
@@ -59,6 +59,7 @@ __FBSDID("$FreeBSD$");
 
 #include "opt_ddb.h"
 #include "opt_compat.h"
+#include "opt_kstack_pages.h"
 #include "opt_msgbuf.h"
 
 #include <sys/param.h>
diff --git a/sys/powerpc/powerpc/mmu_oea.c b/sys/powerpc/powerpc/mmu_oea.c
index 0ef6e0d4304a..4ca3a98dc2a8 100644
--- a/sys/powerpc/powerpc/mmu_oea.c
+++ b/sys/powerpc/powerpc/mmu_oea.c
@@ -114,6 +114,8 @@ __FBSDID("$FreeBSD$");
  * correct.
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/ktr.h>
diff --git a/sys/powerpc/powerpc/pmap.c b/sys/powerpc/powerpc/pmap.c
index 0ef6e0d4304a..4ca3a98dc2a8 100644
--- a/sys/powerpc/powerpc/pmap.c
+++ b/sys/powerpc/powerpc/pmap.c
@@ -114,6 +114,8 @@ __FBSDID("$FreeBSD$");
  * correct.
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/ktr.h>
diff --git a/sys/powerpc/powerpc/vm_machdep.c b/sys/powerpc/powerpc/vm_machdep.c
index b9aa06b640c5..b067b321698f 100644
--- a/sys/powerpc/powerpc/vm_machdep.c
+++ b/sys/powerpc/powerpc/vm_machdep.c
@@ -67,6 +67,8 @@
  * rights to redistribute these changes.
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
diff --git a/sys/sparc64/include/param.h b/sys/sparc64/include/param.h
index 7ee63607d1ad..8a9726c9f677 100644
--- a/sys/sparc64/include/param.h
+++ b/sys/sparc64/include/param.h
@@ -104,7 +104,9 @@
 #define PAGE_SIZE_MAX	PAGE_SIZE_4M
 #define PAGE_MASK_MAX	PAGE_MASK_4M
 
+#ifndef KSTACK_PAGES
 #define KSTACK_PAGES		4	/* pages of kernel stack (with pcb) */
+#endif
 #define KSTACK_GUARD_PAGES	1	/* pages of kstack guard; 0 disables */
 #define UAREA_PAGES		1	/* pages of user area */
 #define PCPU_PAGES		1
diff --git a/sys/sparc64/sparc64/genassym.c b/sys/sparc64/sparc64/genassym.c
index 6360b84f5e6a..ffa3c47667c7 100644
--- a/sys/sparc64/sparc64/genassym.c
+++ b/sys/sparc64/sparc64/genassym.c
@@ -27,6 +27,8 @@
  * $FreeBSD$
  */
 
+#include "opt_kstack_pages.h"
+
 #include <sys/param.h>
 #include <sys/assym.h>
 #include <sys/errno.h>
diff --git a/sys/sparc64/sparc64/machdep.c b/sys/sparc64/sparc64/machdep.c
index aead2a48dade..7bd1451dbb38 100644
--- a/sys/sparc64/sparc64/machdep.c
+++ b/sys/sparc64/sparc64/machdep.c
@@ -42,6 +42,7 @@
 
 #include "opt_compat.h"
 #include "opt_ddb.h"
+#include "opt_kstack_pages.h"
 #include "opt_msgbuf.h"
 
 #include <sys/param.h>
diff --git a/sys/sparc64/sparc64/pmap.c b/sys/sparc64/sparc64/pmap.c
index d884220b5b88..29441cda33e5 100644
--- a/sys/sparc64/sparc64/pmap.c
+++ b/sys/sparc64/sparc64/pmap.c
@@ -63,6 +63,7 @@
  * correct.
  */
 
+#include "opt_kstack_pages.h"
 #include "opt_msgbuf.h"
 #include "opt_pmap.h"
 
diff --git a/sys/sparc64/sparc64/vm_machdep.c b/sys/sparc64/sparc64/vm_machdep.c
index 5b4b9ab299e1..884b55fcc3b8 100644
--- a/sys/sparc64/sparc64/vm_machdep.c
+++ b/sys/sparc64/sparc64/vm_machdep.c
@@ -43,6 +43,7 @@
  * $FreeBSD$
  */
 
+#include "opt_kstack_pages.h"
 #include "opt_pmap.h"
 
 #include <sys/param.h>