YAFFS2とDD

DDでイメージした場合、データ領域のみで Spare エリアを取得しない。

Re: [Yaffs] Access to files on a YAFFS2 image
http://www.aleph1.co.uk/lurker/message/20091102.213411.9b9fd759.pl.html

Nand flash has two areas to it: "inband" data (typically 2048 bytes per page)
and "oob" spare bytes (typically 64 bytes per page). yaffs typically uses
both. dd just copies the data area of a nand flash so that loses all the oob
area.