diff options
Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c')
-rw-r--r-- | arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 21 |
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; |