Index: linux-2.6.14-ck4/kernel/sched.c
===================================================================
--- linux-2.6.14-ck4.orig/kernel/sched.c	2005-11-09 20:58:22.000000000 +1100
+++ linux-2.6.14-ck4/kernel/sched.c	2005-11-09 20:58:27.000000000 +1100
@@ -16,9 +16,9 @@
  *		by Davide Libenzi, preemptible kernel bits by Robert Love.
  *  2003-09-03	Interactivity tuning by Con Kolivas.
  *  2004-04-02	Scheduler domains code by Nick Piggin
- *  2005-09-16	New staircase scheduling policy by Con Kolivas with help
+ *  2005-11-02	New staircase scheduling policy by Con Kolivas with help
  *		from William Lee Irwin III, Zwane Mwaikambo & Peter Williams.
- *		Staircase v12.1
+ *		Staircase v12.2
  */
 
 #include <linux/mm.h>
@@ -779,7 +779,11 @@ static inline void recalc_task_prio(task
 		NS_TO_JIFFIES(sleep_time) < p->slice) {
 			p->flags &= ~PF_NONSLEEP;
 			dec_burst(p);
-			p->totalrun += sleep_time - JIFFIES_TO_NS(p->slice);
+			p->totalrun -= JIFFIES_TO_NS(p->slice);
+			if (sleep_time > p->totalrun)
+				p->totalrun = 0;
+			else
+				p->totalrun -= sleep_time;
 			goto out;
 	}
 
@@ -3431,6 +3435,8 @@ void set_user_nice(task_t *p, long nice)
 	delta = new_prio - old_prio;
 	p->static_prio = NICE_TO_PRIO(nice);
 	p->prio += delta;
+	if (p->burst > burst(p))
+		p->burst = burst(p);
 
 	if (queued) {
 		enqueue_task(p, rq);