mtd nand erase and bad block

[Brian Norris]

Hi,

On Tue, Jun 5, 2012 at 5:17 AM, Artem Bityutskiy <dedekind1 at gmail.com> wrote:
> On Fri, 2012-06-01 at 17:54 +0300, Shmulik Ladkani wrote:
>>
>> My personal preference would be:
>> 1. A new ioctl (MEMSCRUB?)
>> 2. debugfs flag, PER MTD PART (slightly safer than your global flag)
>> 3. global debugfs flag
>>
> Yes, I guess option 1 is the best I think. Option 2 needs too much work.

Just to put my 2 cents in and revive this thread: I'm also interested
in this kind of feature. I personally recompile to disable bad block
tables temporarily whenever I need to reset a flash-based BBT or
unmark a "bad block." But this isn't always so easy for others I deal
with, so I'm all for a feature that can be used by a
relatively-inexperienced user to reset bad block tables, erase bad
block markers, etc.

I like the idea of an ioctl (option 1), since that does not require
recompilation (even in the event that debugfs wasn't enabled) and can
be built into a user-space tool, with appropriate warnings and
prompting for the user, of course. The debugfs ideas seem a little bit
too manual to be useful for anyone but a true driver/kernel developer
and also a little bit too unsafe (a user may want to target a specific
block without disabling bad block checking for all chips or even for
the entire partition).

FWIW, a similar topic was brought up a long time back, with little result:
http://lists.infradead.org/pipermail/linux-mtd/2010-October/032577.html

So Angus, are you going to code this?

Brian