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Date: Tue, 28 Apr 2015 06:56:20 +0200
From: Boris Brezillon <boris.brezillon@free-electrons.com>
To: "Qi Wang =?UTF-8?B?546L6LW3?= (qiwang)" <qiwang@micron.com>
Subject: Re: detect and manage power cut on MLC NAND
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Hi Qi,

Sorry for the late reply (I was quite busy on other projects
lately :-/).

On Mon, 13 Apr 2015 00:44:35 +0000
Qi Wang =E7=8E=8B=E8=B5=B7 (qiwang) <qiwang@micron.com> wrote:


>=20
> Glad to meet in you ELC.

I was glad to meet you too.

> Is there any planning or idea to fix MLC power loss problem?

For the ideas part, I haven't thought about it since my talk at ELC.
I guess the solution proposed on the MTD website is a good starting
point [1].
Some guys are also considering the "avoid any erase/program operation
when you're about to loose power", but as I already explained I think
the MTD/UBI/UBIFS layers should not rely on this assumption and take
appropriate action to prevent any issue caused by unstable bits.

Best Regards,

Boris

[1]http://www.linux-mtd.infradead.org/doc/ubifs.html#L_unstable_bits

--=20
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com