diff --git a/xen/arch/x86/cpu/intel_cacheinfo.c b/xen/arch/x86/cpu/intel_cacheinfo.c
index 9cfb759be0..e88faa7545 100644
--- a/xen/arch/x86/cpu/intel_cacheinfo.c
+++ b/xen/arch/x86/cpu/intel_cacheinfo.c
@@ -186,7 +186,7 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 			cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
 
 			/* If bit 31 is set, this is an unknown format */
-			for ( j = 0 ; j < 3 ; j++ ) {
+			for ( j = 0; j < ARRAY_SIZE(regs); j++ ) {
 				if ( regs[j] >> 31 )
 					regs[j] = 0;
 			}