UBIFS corruption after power cut

[Richard Weinberger]

On Thu, Nov 27, 2014 at 1:48 PM, Anton Habegger
<Anton.Habegger at delta-es.com> wrote:
> Hello
>
> We got an unrecoverable UBI file system after power cut. It happens only ones and it is not reproducible yet.
> U-Boot is able to load a file from this file system, but the recovering part on linux fails.
> The corruption occurs on a powerpc device (mpc5125) with kernel 2.6.34.

IIRC mainline 2.6.34 has no drivers for the mpc5125.
The board support drivers from Freescale I've seen are in a bad shape.
So I'd first investigate into that.
Does your board pass both UBI and MTD tests?

> I tried to overcome this issue with the more recent back port repository from http://git.infradead.org/users/dedekind/ubifs-v2.6.34.git and I also emulated an MTD device with mtdram module on kernel 3.13 (Ubuntu 14.4). Unfortunately both versions aren't able to recover the image.
>
> I see following scenarios:
> - An UBI image created with 2.6.34 can became corrupted with power cuts due to open bugs at this time. This image will be never recoverable. Is this possible?

If UBI did a boo boo the image is corrupted.
Maybe manual recover is possible.

> - There is a misconfiguration somewhere
> - There is a bug in the 3.13

Why a bug in 3.13?

> - Anything else..

Most UBI issues I've seen are related to MTD driver issues.

-- 
Thanks,
//richard