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Date: Mon, 12 May 2014 23:27:53 -0300
From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
To: linux-mtd@lists.infradead.org, David Woodhouse <dwmw2@infradead.org>,
 Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH 2/4] mtd: nand: Account the blocks used by the BBT in the
 ecc_stats
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On 21 Mar 08:57 AM, Ezequiel Garcia wrote:
> Strictly speaking we should be updating the ecc_stats in the master
> MTD object, with the blocks used by the bad block table.
> 
> This is already being done for bad and reserved blocks detected doing
> the BBT search, but not for the blocks used by the BBT itself. This commit
> adds the latter.
> 
> It should be noted that the ecc_stats structure is kept only for userspace
> information, accesible through an ioctl. However, since the master MTD object
> is not tied to any /dev/mtd{N} device node in the filesystem, there's currently
> no way to retrieve this information.
> 
> This ecc_stats is used for the MTD partitions typically allocated and
> registered by mtd_device_parse_register(). These have a device node, but scan
> for bad blocks and updates the ecc_stats in a different code path.
> 
> Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
> --
> For the reasons exposed above, it's not clear we should remove the ecc_stats
> update in the master MTD altogether or simply take account of the BBT blocks
> for consistency. I've chosen the latter, for it seemed a safer changer.
> 
> I'm open to discussion, though.

Brian,

Can you comment a bit on this one? Should I keep this change in v2?
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com