diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 000468bf06ca..52c34651f469 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3167,6 +3167,10 @@ static inline int inline_xattr_size(struct inode *inode)
 	return 0;
 }
 
+/*
+ * Notice: check inline_data flag without inode page lock is unsafe.
+ * It could change at any time by f2fs_convert_inline_page().
+ */
 static inline int f2fs_has_inline_data(struct inode *inode)
 {
 	return is_inode_flag_set(inode, FI_INLINE_DATA);