linux-kernel - Re: [RFC PATCH] mtd: add per NAND partition ECC config

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140211140102.GB23150@localhost>
Date:	Tue, 11 Feb 2014 11:01:03 -0300
From:	Ezequiel Garcia <ezequiel.garcia@...e-electrons.com>
To:	Boris BREZILLON <b.brezillon.dev@...il.com>
Cc:	David Woodhouse <dwmw2@...radead.org>,
	Brian Norris <computersforpeace@...il.com>,
	Maxime Ripard <maxime.ripard@...e-electrons.com>,
	linux-mtd@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH] mtd: add per NAND partition ECC config

Hi Boris,

On Sat, Feb 08, 2014 at 11:26:46AM +0100, Boris BREZILLON wrote:
> This patch aims to add per partition ECC config for NAND devices.
> It defines a new field in the mtd struct to store the mtd ECC config and
> thus each mtd partition device can store its config instead of using the
> default NAND chip config.
> 
> This feature is needed to support the sunxi boot0 paritition case:
> Allwinner boot code (BROM) requires a specific HW ECC for its boot code
> that may not fit the HW NAND requirements for the entire NAND chip.
> 
> Signed-off-by: Boris BREZILLON <b.brezillon.dev@...il.com>
> ---
> Hello,
> 
> This patch is just a draft that implement per partition ECC config.
> It's currently not properly splitted (it should be separated in several
> patches) and not documented either.
> 

Ah, ah...

> There's at least one point that bother me in the current implementation:
> I introduced DT notions in the nand core code by the mean of the get_ecc_ctrl
> callback, and so far this was kept out of mtd/nand core code (I guess it was
> on purpose).
> 
> Please let me know if you see other drawbacks.
> 
> If you think per partition ECC should not be implemented, could you help me
> find a way to handle sunxi specific case decribed above ?
> 
>  drivers/mtd/mtdpart.c          |   23 ++-
>  drivers/mtd/nand/nand_base.c   |  428 ++++++++++++++++++++++++----------------

I really appreciate your effort, but 428 changed lines is a too big and
intrusive change. I must admit I'm not smart enough to review such patches.

I honestly think you'll have better luck getting feedback if you take the time
to properly split and document this.

Yeah, it's annoying and time-consuming, but it's globally cheaper for you to
invest time on making it easier for reviewers and maintainers, than for each
of us to invest the time deciphering this :-)

Just my point of view, of course.
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/