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From: Richard Weinberger <richard@nod.at>
To: Pavel Machek <pavel@ucw.cz>
Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
 cyrille.pitchen@wedev4u.fr, marek.vasut@gmail.com,
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 dwmw2@infradead.org, dedekind1@gmail.com, tharvey@gateworks.com,
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Subject: Re: [PATCH] ubi: Reject MLC NAND
Date: Wed, 07 Mar 2018 09:01:16 +0100
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Pavel,

Am Mittwoch, 7. M=E4rz 2018, 00:18:05 CET schrieb Pavel Machek:
> On Sat 2018-03-03 11:45:54, Richard Weinberger wrote:
> > While UBI and UBIFS seem to work at first sight with MLC NAND, you will
> > most likely lose all your data upon a power-cut or due to read/write
> > disturb.
> > In order to protect users from bad surprises, refuse to attach to MLC
> > NAND.
> >=20
> > Cc: stable@vger.kernel.org
>=20
> That sounds like _really_ bad idea for stable. All it does is it
> removes support for hardware that somehow works.

MLC is not supported and does not work. Full stop.
If someone manages to get it somehow work, either with hardware or software=
=20
hacks they are on their own.
Having it in stable is the only chance we have to get it into vendor kernel=
s.

All this patch does is representing the current state of UBI/UBIFS.

In the last months I got a way too much boards with MLC NAND on my desk whe=
re=20
UBIFS broke. Customers wished they had known before...

Thanks,
//richard