x86, vmi: TSC going backwards check in vmi clocksource

[pandora-kernel.git] / arch / x86 / kernel / vmiclock_32.c

diff --git a/arch/x86/kernel/vmiclock_32.c b/arch/x86/kernel/vmiclock_32.c
index c4c1f9e..bde106c 100644 (file)
--- a/arch/x86/kernel/vmiclock_32.c
+++ b/arch/x86/kernel/vmiclock_32.c
@@ -283,10 +283,13 @@ void __devinit vmi_time_ap_init(void)
 #endif
 
 /** vmi clocksource */
+static struct clocksource clocksource_vmi;
 
 static cycle_t read_real_cycles(void)
 {
-       return vmi_timer_ops.get_cycle_counter(VMI_CYCLES_REAL);
+       cycle_t ret = (cycle_t)vmi_timer_ops.get_cycle_counter(VMI_CYCLES_REAL);
+       return ret >= clocksource_vmi.cycle_last ?
+               ret : clocksource_vmi.cycle_last;
 }
 
 static struct clocksource clocksource_vmi = {