--- /sys/src/9k/k10/archk10.c
+++ /sys/src/9k/k10/archk10.c
@@ -361,7 +361,7 @@ microdelay(int microsecs)
 
 	r = rdtsc();
 	for(t = r + m->cpumhz*microsecs; r < t; r = rdtsc())
-		;
+		pause();
 }
 
 void
@@ -371,5 +371,5 @@ millidelay(int millisecs)
 
 	r = rdtsc();
 	for(t = r + m->cpumhz*1000ull*millisecs; r < t; r = rdtsc())
-		;
+		pause();
 }
--- /sys/src/9k/k10/devarch.c
+++ /sys/src/9k/k10/devarch.c
@@ -521,7 +521,7 @@ archreset(void)
 	outb(0xcf9, i|0x06);				/* RST_CPU transition */
 
 	for(;;)
-		;
+		pause();
 }
 
 /*
--- /sys/src/9k/k10/fns.h
+++ /sys/src/9k/k10/fns.h
@@ -89,6 +89,7 @@ void	outs(int, ushort);
 void	outss(int, void*, int);
 void	outl(int, ulong);
 void	outsl(int, void*, int);
+void	pause(void);
 int	pciscan(int, Pcidev**);
 ulong	pcibarsize(Pcidev*, int);
 int	pcicfgr8(Pcidev*, int);
--- /sys/src/9k/k10/l64v.s
+++ /sys/src/9k/k10/l64v.s
@@ -409,6 +409,10 @@ TEXT setlabel(SB), 1, $-4
 	MOVL	$0, AX				/* return 0 */
 	RET
 
+TEXT pause(SB), 1, $-4
+	PAUSE
+	RET
+
 TEXT halt(SB), 1, $-4
 	CLI
 	CMPL	nrdy(SB), $0
--- /sys/src/9k/k10/main.c
+++ /sys/src/9k/k10/main.c
@@ -130,7 +130,7 @@ squidboy(int apicno)
 		 * used by the spinning core.
 		 */
 		while(!m->online)
-			;
+			pause();
 		apictimerenable();
 		apictprput(0);