diff --git a/block/elevator.c b/block/elevator.c
index 8768a36..5cbd2b3 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -40,6 +40,8 @@ #include <asm/uaccess.h>
 static DEFINE_SPINLOCK(elv_list_lock);
 static LIST_HEAD(elv_list);
 
+#define pd(fmt, args...) 	printk("[%-24s]: " fmt, __FUNCTION__ , ##args);
+
 /*
  * can we safely merge with this request?
  */
@@ -548,6 +550,11 @@ struct request *elv_next_request(request
 		}
 	}
 
+	if (rq && (rq == &q->pre_flush_rq || rq == &q->post_flush_rq ||
+		   rq == &q->bar_rq))
+		pd("%p (%s)\n", rq,
+		   rq == &q->pre_flush_rq ?
+			"pre" : (rq == &q->post_flush_rq ? "post" : "bar"));
 	return rq;
 }
 
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index eac48be..eb1325c 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -30,6 +30,8 @@ #include <linux/interrupt.h>
 #include <linux/cpu.h>
 #include <linux/blktrace_api.h>
 
+#define pd(fmt, args...) 	printk("[%-24s]: " fmt, __FUNCTION__ , ##args);
+
 /*
  * for max sense size
  */
@@ -395,6 +397,9 @@ void blk_ordered_complete_seq(request_qu
 	struct request *rq;
 	int uptodate;
 
+	pd("ordseq=%02x seq=%02x orderr=%d error=%d\n",
+	   q->ordseq, seq, q->orderr, error);
+
 	if (error && !q->orderr)
 		q->orderr = error;
 
@@ -407,6 +412,7 @@ void blk_ordered_complete_seq(request_qu
 	/*
 	 * Okay, sequence complete.
 	 */
+	pd("sequence complete\n");
 	rq = q->orig_bar_rq;
 	uptodate = q->orderr ? q->orderr : 1;
 
@@ -461,6 +467,17 @@ static void queue_flush(request_queue_t 
 static inline struct request *start_ordered(request_queue_t *q,
 					    struct request *rq)
 {
+	struct bio *bio;
+	pd("%p -> %p,%p,%p infl=%u\n",
+	   rq, &q->pre_flush_rq, &q->bar_rq, &q->post_flush_rq, q->in_flight);
+	pd("%p %d %llu %lu %u %u %u %p\n", rq->bio, rq->errors,
+	   (unsigned long long)rq->hard_sector, rq->hard_nr_sectors,
+	   rq->current_nr_sectors, rq->nr_phys_segments, rq->nr_hw_segments,
+	   rq->buffer);
+	for (bio = rq->bio; bio; bio = bio->bi_next)
+		pd("BIO %p %llu %u\n",
+		   bio, (unsigned long long)bio->bi_sector, bio->bi_size);
+
 	q->bi_size = 0;
 	q->orderr = 0;
 	q->ordered = q->next_ordered;
@@ -499,6 +516,7 @@ static inline struct request *start_orde
 	} else
 		q->ordseq |= QUEUE_ORDSEQ_PREFLUSH;
 
+	pd("ordered=%x in_flight=%u\n", q->ordered, q->in_flight);
 	if ((q->ordered & QUEUE_ORDERED_TAG) || q->in_flight == 0)
 		q->ordseq |= QUEUE_ORDSEQ_DRAIN;
 	else
@@ -518,8 +536,10 @@ int blk_do_ordered(request_queue_t *q, s
 
 		if (q->next_ordered != QUEUE_ORDERED_NONE) {
 			*rqp = start_ordered(q, rq);
+			pd("start_ordered %p->%p\n", rq, *rqp);
 			return 1;
 		} else {
+			pd("ORDERED_NONE, seen barrier\n");
 			/*
 			 * This can happen when the queue switches to
 			 * ORDERED_NONE while this request is on it.
@@ -553,6 +573,7 @@ int blk_do_ordered(request_queue_t *q, s
 			*rqp = NULL;
 	}
 
+	pd("seq=%02x %p->%p\n", blk_ordered_cur_seq(q), rq, *rqp);
 	return 1;
 }
 
@@ -585,6 +606,9 @@ static int flush_dry_bio_endio(struct bi
 	bio->bi_sector -= (q->bi_size >> 9);
 	q->bi_size = 0;
 
+	pd("BIO %p %llu %u\n",
+	   bio, (unsigned long long)bio->bi_sector, bio->bi_size);
+
 	return 0;
 }
 
@@ -598,6 +622,7 @@ static inline int ordered_bio_endio(stru
 	if (&q->bar_rq != rq)
 		return 0;
 
+	pd("q->orderr=%d error=%d\n", q->orderr, error);
 	/*
 	 * Okay, this is the barrier request in progress, dry finish it.
 	 */
@@ -2864,6 +2889,7 @@ static int __make_request(request_queue_
 
 	barrier = bio_barrier(bio);
 	if (unlikely(barrier) && (q->next_ordered == QUEUE_ORDERED_NONE)) {
+		pd("ORDERED_NONE, seen barrier\n");
 		err = -EOPNOTSUPP;
 		goto end_io;
 	}