1 files changed, 9 insertions, 1 deletions

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 69a69c3f43bb..9f45a51af968 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -285,9 +285,17 @@ static void mwait_idle(void)
         mwait_idle_with_hints(0, 0);
 }
 
+static int mwait_usable(const struct cpuinfo_x86 *c)
+{
+        if (force_mwait)
+                return 1;
+        /* Any C1 states supported? */
+        return c->cpuid_level >= 5 && ((cpuid_edx(5) >> 4) & 0xf) > 0;
+}
+
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 {
-        if (cpu_has(c, X86_FEATURE_MWAIT)) {
+        if (cpu_has(c, X86_FEATURE_MWAIT) && mwait_usable(c)) {
                 printk("monitor/mwait feature present.\n");
                 /*
                  * Skip, if setup has overridden idle.