1 files changed, 17 insertions, 2 deletions

diff --git a/arch/i386/kernel/timers/timer_tsc.c b/arch/i386/kernel/timers/timer_tsc.c
index 47675bbbb316..a7f5a2aceba2 100644
--- a/arch/i386/kernel/timers/timer_tsc.c
+++ b/arch/i386/kernel/timers/timer_tsc.c
@@ -45,6 +45,15 @@ static unsigned long last_tsc_high; /* msb 32 bits of Time Stamp Counter */
 static unsigned long long monotonic_base;
 static seqlock_t monotonic_lock = SEQLOCK_UNLOCKED;
 
+/* Avoid compensating for lost ticks before TSCs are synched */
+static int detect_lost_ticks;
+static int __init start_lost_tick_compensation(void)
+{
+        detect_lost_ticks = 1;
+        return 0;
+}
+late_initcall(start_lost_tick_compensation);
+
 /* convert from cycles(64bits) => nanoseconds (64bits)
  *  basic equation:
  *              ns = cycles / (freq / ns_per_sec)
@@ -196,7 +205,8 @@ static void mark_offset_tsc_hpet(void)
 
         /* lost tick compensation */
         offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
-        if (unlikely(((offset - hpet_last) > hpet_tick) && (hpet_last != 0))) {
+        if (unlikely(((offset - hpet_last) > hpet_tick) && (hpet_last != 0))
+                                        && detect_lost_ticks) {
                 int lost_ticks = (offset - hpet_last) / hpet_tick;
                 jiffies_64 += lost_ticks;
         }
@@ -272,6 +282,10 @@ time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
         if (val != CPUFREQ_RESUMECHANGE)
                 write_seqlock_irq(&xtime_lock);
         if (!ref_freq) {
+                if (!freq->old){
+                        ref_freq = freq->new;
+                        goto end;
+                }
                 ref_freq = freq->old;
                 loops_per_jiffy_ref = cpu_data[freq->cpu].loops_per_jiffy;
 #ifndef CONFIG_SMP
@@ -297,6 +311,7 @@ time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
 #endif
         }
 
+end:
         if (val != CPUFREQ_RESUMECHANGE)
                 write_sequnlock_irq(&xtime_lock);
 
@@ -421,7 +436,7 @@ static void mark_offset_tsc(void)
         delta += delay_at_last_interrupt;
         lost = delta/(1000000/HZ);
         delay = delta%(1000000/HZ);
-        if (lost >= 2) {
+        if (lost >= 2 && detect_lost_ticks) {
                 jiffies_64 += lost-1;
 
                 /* sanity check to ensure we're not always losing ticks */