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Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c')
-rw-r--r--arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
index 4109679863c..7bb676c533a 100644
--- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -526,6 +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
+ * 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*/
+ if (c->x86_vendor == X86_VENDOR_INTEL) {
+ if ((c->x86 == 15) &&
+ (c->x86_model == 6) &&
+ (c->x86_mask == 8) && smt_capable())
+ return -ENODEV;
+ }
+ return 0;
+}
#endif
static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
@@ -540,6 +555,12 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
dprintk("acpi_cpufreq_cpu_init\n");
+#ifdef CONFIG_SMP
+ result = acpi_cpufreq_blacklist(c);
+ if (result)
+ return result;
+#endif
+
data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
if (!data)
return -ENOMEM;