Re: mtd/fs/jffs2 erase.c,1.84,1.85 roll back

Artem B. Bityutskiy
2005-09-26T08:30:15Z

Jörn Engel wrote:
> On Fri, 23 September 2005 17:22:53 +0200, Anders Grafstrom wrote:
>
>>jffs2 makes a second try if a failed erase is reported by the mtd
>>driver. But only for NAND (in jffs2_write_nand_badblock()). What I'm
>>after is a retry for NOR as well. But I wrote the patch so it would
>>retry for other cases of failure too.
>
> Is a retry really an improvement? When a block cannot be properly
> erased on the first try, I would not trust it anymore. Instead of a
> retry, I'd rather mark it as a bad block and not touch it again.

From the other hand, why not to retry? Does it hurt? Is this in the
critical code-path? Deity knows what happend to the hardware/driver, may
be there was a short magnetical disturbance and that was the reason why
the block was not erased. May be one of the lines/cirquits outside of
the flash was affected but the block is really erasable. Actually, after
I've read the paper that *you* pointed
(http://www.cs.wisc.edu/adsl/Publications/iron-sosp05.pdf), I'm rather
positive about the idea of retrying. The articlae is about HDDs, but IMO
is also acceptable flash devices in this respect.

--
Best Regards,
Artem B. Bityuckiy,
St.-Petersburg, Russia.