1 files changed, 17 insertions, 6 deletions

diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
index 7d5c3b0ea8da..8b581d3905cb 100644
--- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -526,15 +526,21 @@ static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 
 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 {
-        /* http://www.intel.com/Assets/PDF/specupdate/314554.pdf
+        /* Intel Xeon Processor 7100 Series Specification Update
+         * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
          * AL30: A Machine Check Exception (MCE) Occurring during an
          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
-         * Both Processor Cores to Lock Up when HT is enabled*/
+         * Both Processor Cores to Lock Up. */
         if (c->x86_vendor == X86_VENDOR_INTEL) {
                 if ((c->x86 == 15) &&
                     (c->x86_model == 6) &&
-                    (c->x86_mask == 8) && smt_capable())
+                    (c->x86_mask == 8)) {
+                        printk(KERN_INFO "acpi-cpufreq: Intel(R) "
+                            "Xeon(R) 7100 Errata AL30, processors may "
+                            "lock up on frequency changes: disabling "
+                            "acpi-cpufreq.\n");
                         return -ENODEV;
+                    }
                 }
         return 0;
 }
@@ -549,13 +555,18 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
         unsigned int result = 0;
         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
         struct acpi_processor_performance *perf;
+#ifdef CONFIG_SMP
+        static int blacklisted;
+#endif
 
         dprintk("acpi_cpufreq_cpu_init\n");
 
 #ifdef CONFIG_SMP
-        result = acpi_cpufreq_blacklist(c);
-        if (result)
-                return result;
+        if (blacklisted)
+                return blacklisted;
+        blacklisted = acpi_cpufreq_blacklist(c);
+        if (blacklisted)
+                return blacklisted;
 #endif
 
         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);