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Subject: Re: Understanding OOB data read implementation (II)
From: Artem Bityutskiy <dedekind1@gmail.com>
To: David Peverley <pev@sketchymonkey.com>
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Date: Sat, 16 Oct 2010 22:37:22 +0300
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On Fri, 2010-10-15 at 12:29 +0100, David Peverley wrote:
> Hi again...!
> 
> I've also noticed after blindly copying it that in the DoC drivers
> that the OOB reads use the ops->len for size :
>     static int doc_read_oob(struct mtd_info *mtd, loff_t ofs,
>                             struct mtd_oob_ops *ops)
>         ...
>         uint8_t *buf = ops->oobbuf;
>         size_t len = ops->len;
>         ...
> 
> Reading mtd.h and the following patch summary :
>     http://www.mail-archive.com/git-commits-head@vger.kernel.org/msg03799.html
> 
> I suspect this is wrong and should be using ops->ooblen instead. This
> is especially true given that mtdchar.c leaves ops->len
> uninitialised....! (should mtdchar.c:mtd_do_readoob() not zero the ops
> structure as it's a local automatic so not zero-initialised?) Again
> this is copied in doc2001.c and doc2001plus.c.

If you can test the change - please send a patch.

-- 
Best Regards,
Artem Bityutskiy (Битюцкий Артём)