--- linux-2.6.8.1-mm1/fs/ext3/balloc.c.=K0006=.orig
+++ linux-2.6.8.1-mm1/fs/ext3/balloc.c
@@ -20,6 +20,12 @@
 #include <linux/quotaops.h>
 #include <linux/buffer_head.h>
 
+#if 0
+#define dprintk(msg...) printk(msg)
+#else
+#define dprintk(msg...) do { } while(0)
+#endif
+
 /*
  * balloc.c contains the blocks allocation and deallocation routines
  */
@@ -110,7 +116,7 @@ error_out:
  * we could easily switch to that without changing too much
  * code.
  */
-#if 0
+#if 1
 static void __rsv_window_dump(struct rb_root *root, int verbose, 
 			      const char *fn)
 {
@@ -213,6 +219,17 @@ static struct reserve_window_node *searc
 	if (rsv->rsv_start > goal) {
 		n = rb_prev(&rsv->rsv_node);
 		rsv = rb_entry(n, struct reserve_window_node, rsv_node);
+		if (rsv->rsv_start > goal)
+			BUG();
+	}
+	{
+		struct reserve_window_node *next;
+		n = rb_next(&rsv->rsv_node);
+		if (n) {
+			next = rb_entry(n, struct reserve_window_node, rsv_node);
+			if (next->rsv_start < goal)
+				BUG();
+		}
 	}
 	return rsv; 
 }
@@ -227,6 +244,8 @@ void rsv_window_add(struct super_block *
 	struct rb_node ** p = &root->rb_node;
 	struct rb_node * parent = NULL;
 	struct reserve_window_node *this;
+
+	static int debug_counter = 0;
 	
 	while (*p)
 	{
@@ -237,12 +256,29 @@ void rsv_window_add(struct super_block *
 			p = &(*p)->rb_left;
 		else if (start > this->rsv_end)
 			p = &(*p)->rb_right;
-		else
+		else {
+			/* We should never be adding a reservation which 
+			 * overlaps an existing one */
+			printk(KERN_ALERT 
+			       "Whoops, got a reservation overlap:\n"
+			       "old %p start %u end %u goal_size %d\n"
+			       "new %p start %u end %u goal_size %d\n",
+			       this, this->rsv_start, this->rsv_end, 
+			       atomic_read(&this->rsv_goal_size),
+			       rsv, rsv->rsv_start, rsv->rsv_end,
+			       atomic_read(&rsv->rsv_goal_size));
+			rsv_window_dump(root, 1);
 			BUG();
+		}
 	}
 
 	rb_link_node(node, parent, p);
 	rb_insert_color(node, root);
+
+	if (++debug_counter > 1000) {
+		rsv_window_dump(root, 0);
+		debug_counter = 0;
+	}
 }
 
 static void rsv_window_remove(struct super_block *sb,
@@ -716,6 +752,9 @@ static struct reserve_window_node *find_
 	if (!rsv) 
 		return NULL;
 	
+	dprintk(KERN_DEBUG "%s: starting from 0x%p @ %d, looking for %d\n",
+		__FUNCTION__, search_head, rsv->rsv_start, cur);
+
 	while (1) {
 		if (cur <= rsv->rsv_end)
 			cur = rsv->rsv_end + 1;
@@ -735,6 +774,8 @@ static struct reserve_window_node *find_
 		prev = rsv;
 		next = rb_next(&rsv->rsv_node);
 		rsv = list_entry(next, struct reserve_window_node, rsv_node);
+		dprintk(KERN_DEBUG "%s: looking at 0x%p [%d]\n",
+			__FUNCTION__, rsv, rsv->rsv_start);
 
 		/* 
 		 * Reached the last reservation, we can just append to the 
@@ -856,6 +897,8 @@ static int alloc_new_reservation(struct 
 		if (my_rsv->rsv_end + 1 > start_block)
 			start_block = my_rsv->rsv_end + 1;
 		search_head = my_rsv;
+		dprintk(KERN_DEBUG "%s: search starting from 0x%p (@%d)\n", 
+			__FUNCTION__, search_head, search_head->rsv_start);
 		if ((atomic_read(&my_rsv->rsv_alloc_hit) > 
 		     (my_rsv->rsv_end - my_rsv->rsv_start + 1) / 2)) {
 			/*
@@ -876,6 +919,8 @@ static int alloc_new_reservation(struct 
 		 * the list head for the search
 		 */
 		search_head = search_reserve_window(fs_rsv_root, start_block);
+		dprintk(KERN_DEBUG "%s: search returned 0x%p\n", 
+			__FUNCTION__, search_head);
 	}
 
 	/*
@@ -888,6 +933,9 @@ static int alloc_new_reservation(struct 
 retry:
 	prev_rsv = find_next_reservable_window(search_head, size,
 						&start_block, group_end_block);
+	dprintk(KERN_DEBUG "%s: found window 0x%p, block %d\n",
+		__FUNCTION__, prev_rsv, start_block);
+	
 	if (prev_rsv == NULL)
 		goto failed;
 	reservable_space_start = start_block;
@@ -929,6 +977,8 @@ retry:
 	 * we also shift the list head to where we stopped last time
 	 */
 	search_head = prev_rsv;
+	dprintk (KERN_DEBUG "%s: retrying from 0x%p @%d\n",
+		 __FUNCTION__, prev_rsv, prev_rsv->rsv_start);
 	goto retry;
 
 found_rsv_window:
@@ -1062,8 +1112,12 @@ ext3_try_to_allocate_with_rsv(struct sup
 				goal = -1;
 		}
 		if ((rsv_copy._rsv_start >= group_first_block + EXT3_BLOCKS_PER_GROUP(sb))
-		    || (rsv_copy._rsv_end < group_first_block))
+		    || (rsv_copy._rsv_end < group_first_block)) {
+			printk("Whoops, invalid reservation %p (%d to %d)\n",
+			       my_rsv, my_rsv->rsv_start, my_rsv->rsv_end);
+			rsv_window_dump(&EXT3_SB(sb)->s_rsv_window_root, 1);
 			BUG();
+		}
 		ret = ext3_try_to_allocate(sb, handle, group, bitmap_bh, goal,
 					   &rsv_copy);
 		if (ret >= 0) {