diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 86eff48..503a6bd 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -995,6 +995,8 @@
 		bytes = min(bytes, working_bytes);
 		kaddr = kmap_atomic(page_out);
 		memcpy(kaddr + *pg_offset, buf + buf_offset, bytes);
+		if (*pg_index == (vcnt - 1) && *pg_offset == 0)
+			memset(kaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
 		kunmap_atomic(kaddr);
 		flush_dcache_page(page_out);