[liberationtech] secure wipe of flash memory

[Chris Ball]

Hi,

On Sat, Jul 21 2012, Michael Rogers wrote:
> Does anyone on the list know whether flash controller chips use
> journalling? I'm guessing they might because YAFFS does.

I don't think so -- YAFFS is a filesystem, and the wear-leveling
algorithm on the controller only knows how to act on reads/writes
to individual blocks on the flash, so they're very different layers.
The flash controller isn't a replacement for a filesystem; you
still need to use one, and it may or may not be journaled.

(Although the independence between wear-leveling algorithm and
filesystem isn't total; there's evidence that the vendors teach
their firmware how to handle writes to the Windows FAT cleanly.)

- Chris.
-- 
Chris Ball   <cjb at laptop.org>   <http://printf.net/>
One Laptop Per Child