diff --git a/mm/rmap.c b/mm/rmap.c
index cdc2a88..68af2e3 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1411,6 +1411,11 @@
 	 */
 }
 
+struct rmap_private {
+	enum ttu_flags flags;
+	int lazyfreed;
+};
+
 /*
  * @arg: enum ttu_flags will be passed to this argument
  */
@@ -1422,7 +1427,8 @@
 	pte_t pteval;
 	spinlock_t *ptl;
 	int ret = SWAP_AGAIN;
-	enum ttu_flags flags = (enum ttu_flags)arg;
+	struct rmap_private *rp = arg;
+	enum ttu_flags flags = rp->flags;
 
 	/* munlock has nothing to gain from examining un-locked vmas */
 	if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED))
@@ -1514,6 +1520,14 @@
 		 * See handle_pte_fault() ...
 		 */
 		VM_BUG_ON_PAGE(!PageSwapCache(page), page);
+
+		if (!PageDirty(page) && (flags & TTU_LZFREE)) {
+			/* It's a freeable page by MADV_FREE */
+			dec_mm_counter(mm, MM_ANONPAGES);
+			rp->lazyfreed++;
+			goto discard;
+		}
+
 		if (swap_duplicate(entry) < 0) {
 			set_pte_at(mm, address, pte, pteval);
 			ret = SWAP_FAIL;
@@ -1534,6 +1548,7 @@
 	} else
 		dec_mm_counter(mm, mm_counter_file(page));
 
+discard:
 	page_remove_rmap(page, PageHuge(page));
 	page_cache_release(page);
 
@@ -1586,9 +1601,14 @@
 int try_to_unmap(struct page *page, enum ttu_flags flags)
 {
 	int ret;
+	struct rmap_private rp = {
+		.flags = flags,
+		.lazyfreed = 0,
+	};
+
 	struct rmap_walk_control rwc = {
 		.rmap_one = try_to_unmap_one,
-		.arg = (void *)flags,
+		.arg = &rp,
 		.done = page_not_mapped,
 		.anon_lock = page_lock_anon_vma_read,
 	};
@@ -1608,8 +1628,11 @@
 
 	ret = rmap_walk(page, &rwc);
 
-	if (ret != SWAP_MLOCK && !page_mapped(page))
+	if (ret != SWAP_MLOCK && !page_mapped(page)) {
 		ret = SWAP_SUCCESS;
+		if (rp.lazyfreed && !PageDirty(page))
+			ret = SWAP_LZFREE;
+	}
 	return ret;
 }
 
@@ -1631,9 +1654,14 @@
 int try_to_munlock(struct page *page)
 {
 	int ret;
+	struct rmap_private rp = {
+		.flags = TTU_MUNLOCK,
+		.lazyfreed = 0,
+	};
+
 	struct rmap_walk_control rwc = {
 		.rmap_one = try_to_unmap_one,
-		.arg = (void *)TTU_MUNLOCK,
+		.arg = &rp,
 		.done = page_not_mapped,
 		.anon_lock = page_lock_anon_vma_read,