1 files changed, 12 insertions, 0 deletions

diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index d735cb460612..dfd243f497b2 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -688,6 +688,18 @@ static int __init longhaul_init(void)
         if (c->x86_vendor != X86_VENDOR_CENTAUR || c->x86 != 6)
                 return -ENODEV;
 
+#ifdef CONFIG_SMP
+        if (num_online_cpus() > 1) {
+                return -ENODEV;
+                printk(KERN_ERR PFX "More than 1 CPU detected, longhaul disabled.\n");
+        }
+#endif
+#ifdef CONFIG_X86_IO_APIC
+        if (cpu_has_apic) {
+                printk(KERN_ERR PFX "APIC detected. Longhaul is currently broken in this configuration.\n");
+                return -ENODEV;
+        }
+#endif
         switch (c->x86_model) {
         case 6 ... 9:
                 return cpufreq_register_driver(&longhaul_driver);