diff -ru -x '*~' linux-2.6.32.24-orig/arch/x86/kernel/pvclock.c linux-2.6.32.24/arch/x86/kernel/pvclock.c
--- linux-2.6.32.24-orig/arch/x86/kernel/pvclock.c	2010-10-01 22:51:56.000000000 +0200
+++ linux-2.6.32.24/arch/x86/kernel/pvclock.c	2010-10-25 14:02:14.000000000 +0200
@@ -109,14 +109,11 @@
 	return pv_tsc_khz;
 }
 
-static atomic64_t last_value = ATOMIC64_INIT(0);
-
 cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src)
 {
 	struct pvclock_shadow_time shadow;
 	unsigned version;
 	cycle_t ret, offset;
-	u64 last;
 
 	do {
 		version = pvclock_get_time_values(&shadow, src);
@@ -126,27 +123,6 @@
 		barrier();
 	} while (version != src->version);
 
-	/*
-	 * Assumption here is that last_value, a global accumulator, always goes
-	 * forward. If we are less than that, we should not be much smaller.
-	 * We assume there is an error marging we're inside, and then the correction
-	 * does not sacrifice accuracy.
-	 *
-	 * For reads: global may have changed between test and return,
-	 * but this means someone else updated poked the clock at a later time.
-	 * We just need to make sure we are not seeing a backwards event.
-	 *
-	 * For updates: last_value = ret is not enough, since two vcpus could be
-	 * updating at the same time, and one of them could be slightly behind,
-	 * making the assumption that last_value always go forward fail to hold.
-	 */
-	last = atomic64_read(&last_value);
-	do {
-		if (ret < last)
-			return last;
-		last = atomic64_cmpxchg(&last_value, last, ret);
-	} while (unlikely(last != ret));
-
 	return ret;
 }