Index: sys/vm/vm_fault.c
===================================================================
--- sys/vm/vm_fault.c
+++ sys/vm/vm_fault.c
@@ -1853,59 +1853,53 @@
 static void
 vm_fault_dontneed(const struct faultstate *fs, vm_offset_t vaddr, int ahead)
 {
+	struct pctrie_iter pages;
 	vm_map_entry_t entry;
 	vm_object_t first_object;
 	vm_offset_t end, start;
-	vm_page_t m, m_next;
-	vm_pindex_t pend, pstart;
+	vm_page_t m;
 	vm_size_t size;
 
 	VM_OBJECT_ASSERT_UNLOCKED(fs->object);
 	first_object = fs->first_object;
 	/* Neither fictitious nor unmanaged pages can be reclaimed. */
-	if ((first_object->flags & (OBJ_FICTITIOUS | OBJ_UNMANAGED)) == 0) {
-		VM_OBJECT_RLOCK(first_object);
-		size = VM_FAULT_DONTNEED_MIN;
-		if (MAXPAGESIZES > 1 && size < pagesizes[1])
-			size = pagesizes[1];
-		end = rounddown2(vaddr, size);
-		if (vaddr - end >= size - PAGE_SIZE - ptoa(ahead) &&
-		    (entry = fs->entry)->start < end) {
-			if (end - entry->start < size)
-				start = entry->start;
-			else
-				start = end - size;
-			pmap_advise(fs->map->pmap, start, end, MADV_DONTNEED);
-			pstart = OFF_TO_IDX(entry->offset) + atop(start -
-			    entry->start);
-			m_next = vm_page_find_least(first_object, pstart);
-			pend = OFF_TO_IDX(entry->offset) + atop(end -
-			    entry->start);
-			while ((m = m_next) != NULL && m->pindex < pend) {
-				m_next = TAILQ_NEXT(m, listq);
-				if (!vm_page_all_valid(m) ||
-				    vm_page_busied(m))
-					continue;
+	if ((first_object->flags & (OBJ_FICTITIOUS | OBJ_UNMANAGED)) != 0)
+		return;
+	VM_OBJECT_RLOCK(first_object);
+	size = VM_FAULT_DONTNEED_MIN;
+	if (MAXPAGESIZES > 1 && size < pagesizes[1])
+		size = pagesizes[1];
+	end = rounddown2(vaddr, size);
+	if (vaddr - end < size - PAGE_SIZE - ptoa(ahead) ||
+	    (entry = fs->entry)->start >= end)
+		return;
+	if (end - entry->start < size)
+		start = entry->start;
+	else
+		start = end - size;
+	pmap_advise(fs->map->pmap, start, end, MADV_DONTNEED);
+	vm_page_iter_limit_init(&pages, first_object,
+	    OFF_TO_IDX(entry->offset) + atop(end - entry->start));
+	VM_RADIX_FOREACH_FROM(m, &pages,
+	    OFF_TO_IDX(entry->offset) + atop(start - entry->start)) {
+		if (!vm_page_all_valid(m) ||
+		    vm_page_busied(m))
+			continue;
 
-				/*
-				 * Don't clear PGA_REFERENCED, since it would
-				 * likely represent a reference by a different
-				 * process.
-				 *
-				 * Typically, at this point, prefetched pages
-				 * are still in the inactive queue.  Only
-				 * pages that triggered page faults are in the
-				 * active queue.  The test for whether the page
-				 * is in the inactive queue is racy; in the
-				 * worst case we will requeue the page
-				 * unnecessarily.
-				 */
-				if (!vm_page_inactive(m))
-					vm_page_deactivate(m);
-			}
-		}
-		VM_OBJECT_RUNLOCK(first_object);
+		/*
+		 * Don't clear PGA_REFERENCED, since it would likely represent a
+		 * reference by a different process.
+		 *
+		 * Typically, at this point, prefetched pages are still in the
+		 * inactive queue.  Only pages that triggered page faults are in
+		 * the active queue.  The test for whether the page is in the
+		 * inactive queue is racy; in the worst case we will requeue the
+		 * page unnecessarily.
+		 */
+		if (!vm_page_inactive(m))
+			vm_page_deactivate(m);
 	}
+	VM_OBJECT_RUNLOCK(first_object);
 }
 
 /*