Re: [PATCH] mtd: nand: realtek-ecc: relax OOB size check to minimum

[Ahmed Naseef]

On Fri, Feb 06, 2026 at 12:11:20PM +0100, markus.stockhausen@xxxxxx wrote:

Hi Markus,

Thanks for the review.

> Hi Ahmed,
> 
> thanks for that finding.
> 
> > Von: Ahmed Naseef <naseefkm@xxxxxxxxx> 
> > Gesendet: Freitag, 6. Februar 2026 11:58
> > Betreff: [PATCH] mtd: nand: realtek-ecc: relax OOB size check to minimum
> >
> > ...
> >
> > Signed-off-by: Ahmed Naseef <naseefkm@xxxxxxxxx>
> > Suggested-by: Markus Stockhausen <markus.stockhausen@xxxxxx>
> 
> IIRC this should be the other way round.
> 
Could you clarify what you meant by "the other way round" — do you
mean the ordering of the Suggested-by/Signed-off-by tags, or the
attribution itself?
> > ...
> >  * are only two known devices in the wild that have NAND flash and make use of this ECC engine
> >  * (Linksys LGS328C & LGS352C). To keep compatibility with vendor firmware, new modes can only
> 
> Now it is more than these two devices. Please adapt the whole description so it
> gives a consistent explanation.
> 
Regarding the comment about the two known devices — I was planning
to update it to something like:

    * It can run for arbitrary NAND flash chips with different block and OOB sizes. Currently there
    * are a few known devices in the wild that have NAND flash and make use of this ECC engine
    * (Linksys LGS328C, LGS352C & Netlink HG323DAC). To keep compatibility with vendor firmware,
    * new modes can only be added when new data layouts have been analyzed. For now allow BCH6 on
    * flash with 2048 byte blocks and at least 64 bytes oob.Some NAND chips (e.g. Macronix 
    * MX35LF1G24AD) have a physical OOB size of 128 bytes but vendor firmware only uses the first
    * 64 bytes for the ECC layout. The engine operates on the first 64 bytes of OOB only; any extra
    * bytes are unused.

Does that look reasonable to you, or would you prefer a different wording?

I'll send a v2 once I have your feedback.

Thanks,
Ahmed Naseef