Hi Charles, I find these function which not deal with the result when the ecc error ? can you give some suggestion ? Yes is done,no is not. yaffs_check_chunk_erased yes yaffs_verify_chunk_written no yaffs_find_chunk_in_group no yaffs_put_chunk_in_file no yaffs_gc_process_chunk no yaffs_rd_data_obj no yaffs_do_xattrib_fetch yes yaffs_check_obj_details_loaded no yaffs_update_oh no yaffs_get_obj_name no yaffs_summary_read yes yaffs_verify_file no yaffs_verify_obj no yaffs1_scan yes yaffs2_scan_chunk£¨1£© yes yaffs2_scan_chunk£¨2£© no yaffs2_checkpt_find_block no yaffs2_checkpt_rd yes yaffs_rd_chunk_tags_nand yes yaffs_tags_marshall_query_block no When the chunk is obj_header ,we can drop it ; but when the date error how can we deal with ? fill the chunk with 0 ? ¡°yaffs_gc_process_chunk¡± the function how to deal ?