Index: linux-2.6.17/mm/swap_prefetch.c
===================================================================
--- linux-2.6.17.orig/mm/swap_prefetch.c	2006-07-03 13:11:06.000000000 -0700
+++ linux-2.6.17/mm/swap_prefetch.c	2006-07-03 13:12:08.000000000 -0700
@@ -277,8 +277,10 @@
 
 		ns = &sp_stat.node[z->zone_pgdat->node_id];
 		idx = zone_idx(z);
-		ns->lowfree[idx] = z->pages_high * 3 +
-			z->lowmem_reserve[ZONE_HIGHMEM];
+		ns->lowfree[idx] = z->pages_high * 3;
+#ifdef CONFIG_HIGHMEM
+		ns->lowfree[idx] += z->lowmem_reserve[ZONE_HIGHMEM];
+#endif
 		ns->highfree[idx] = ns->lowfree[idx] + z->pages_high;
 
 		if (z->free_pages > ns->highfree[idx]) {