diff --git a/sys/ia64/ia64/mp_machdep.c b/sys/ia64/ia64/mp_machdep.c
index ff1a377b9164..d3ee570fbadf 100644
--- a/sys/ia64/ia64/mp_machdep.c
+++ b/sys/ia64/ia64/mp_machdep.c
@@ -28,11 +28,11 @@
 
 #include <sys/param.h>
 #include <sys/systm.h>
-#include <sys/mutex.h>
 #include <sys/ktr.h>
 #include <sys/proc.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
+#include <sys/mutex.h>
 #include <sys/kernel.h>
 #include <sys/sysctl.h>
 
@@ -58,9 +58,9 @@ volatile u_int		started_cpus;
 volatile u_int		checkstate_probed_cpus;
 volatile u_int		checkstate_need_ast;
 volatile u_int		checkstate_pending_ast;
-struct proc*		checkstate_curproc[NCPUS];
-int			checkstate_cpustate[NCPUS];
-u_long			checkstate_pc[NCPUS];
+struct proc*		checkstate_curproc[MAXCPU];
+int			checkstate_cpustate[MAXCPU];
+u_long			checkstate_pc[MAXCPU];
 volatile u_int		resched_cpus;
 void (*cpustop_restartfunc) __P((void));
 int			mp_ncpus;
@@ -69,7 +69,7 @@ int			smp_started;
 int			boot_cpu_id;
 u_int32_t		all_cpus;
 
-static struct globaldata	*cpuid_to_globaldata[NCPUS];
+static struct globaldata	*cpuid_to_globaldata[MAXCPU];
 
 int smp_active = 0;	/* are the APs allowed to run? */
 SYSCTL_INT(_machdep, OID_AUTO, smp_active, CTLFLAG_RW, &smp_active, 0, "");
diff --git a/sys/ia64/include/param.h b/sys/ia64/include/param.h
index db2271fbcfea..62e3235c80b3 100644
--- a/sys/ia64/include/param.h
+++ b/sys/ia64/include/param.h
@@ -91,7 +91,11 @@
 #define OBJFORMAT_NAMES		"elf"
 #define OBJFORMAT_DEFAULT	"elf"
 
-#define NCPUS		1
+#ifdef SMP
+#define	MAXCPU		16
+#else
+#define MAXCPU		1
+#endif
 
 /*
  * Round p (pointer or byte index) up to a correctly-aligned value for all