--- /usr/src/sys/i386/i386/mp_machdep.c	2007-07-26 20:04:53.000000000 +0200
+++ i386/i386/mp_machdep.c	2007-07-27 01:10:44.000000000 +0200
@@ -248,8 +248,15 @@
 	int cpu;
 
 	/* Build the smp_topology map. */
-	/* Nothing to do if there is no HTT support. */
-	if ((cpu_feature & CPUID_HTT) == 0)
+	/*
+	 * HTT support detected through CNXT-ID bit.  CNXT-ID assumes L1
+	 * caches shared between CPUs, which designes a less aggressive
+	 * scheduling algorithm.
+	 * In this case, if cores don'tshare the same L1 caches, there is
+	 * nothing to do.
+	 */
+	if ((cpu_feature & CPUID_HTT) == 0 ||
+	    (cpu_feature2 & CPUID2_CNXTID) == 0)
 		return;
 	logical_cpus = (cpu_procinfo & CPUID_HTT_CORES) >> 16;
 	if (logical_cpus <= 1)
@@ -423,7 +430,7 @@
 
 	/* Setup the initial logical CPUs info. */
 	logical_cpus = logical_cpus_mask = 0;
-	if (cpu_feature & CPUID_HTT)
+	if ((cpu_feature & CPUID_HTT) && (cpu_feature2 & CPUID2_CNXTID))
 		logical_cpus = (cpu_procinfo & CPUID_HTT_CORES) >> 16;
 
 	/*
@@ -441,7 +448,7 @@
 	 * First determine if this is an Intel processor which claims
 	 * to have hyperthreading support.
 	 */
-	if ((cpu_feature & CPUID_HTT) &&
+	if ((cpu_feature & CPUID_HTT) && (cpu_feature2 & CPUID2_CNXTID) &&
 	    (strcmp(cpu_vendor, "GenuineIntel") == 0)) {
 		/*
 		 * If the "deterministic cache parameters" cpuid calls
--- /usr/src/sys/amd64/amd64/mp_machdep.c	Thu Jun  7 23:32:44 2007
+++ amd64/amd64/mp_machdep.c	Fri Jul 27 01:44:15 2007
@@ -194,7 +194,8 @@
 
 	/* Build the smp_topology map. */
 	/* Nothing to do if there is no HTT support. */
-	if ((cpu_feature & CPUID_HTT) == 0)
+	if ((cpu_feature & CPUID_HTT) == 0 ||
+	    (cpu_feature2 & CPUID2_CNXTID) == 0)
 		return;
 	logical_cpus = (cpu_procinfo & CPUID_HTT_CORES) >> 16;
 	if (logical_cpus <= 1)
@@ -374,7 +375,7 @@
 
 	/* Setup the initial logical CPUs info. */
 	logical_cpus = logical_cpus_mask = 0;
-	if (cpu_feature & CPUID_HTT)
+	if ((cpu_feature & CPUID_HTT) && (cpu_feature2 & CPUID2_CNXTID))
 		logical_cpus = (cpu_procinfo & CPUID_HTT_CORES) >> 16;
 
 	/*
@@ -392,7 +393,7 @@
 	 * First determine if this is an Intel processor which claims
 	 * to have hyperthreading support.
 	 */
-	if ((cpu_feature & CPUID_HTT) &&
+	if ((cpu_feature & CPUID_HTT) && (cpu_feature2 & CPUID2_CNXTID) &&
 	    (strcmp(cpu_vendor, "GenuineIntel") == 0)) {
 		/*
 		 * If the "deterministic cache parameters" cpuid calls