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Subject: Re: UBI and volume checksum
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Giovanni Malfara' <Giovanni.Malfara.ext@altran.it>
Date: Thu, 07 Jun 2012 15:51:41 +0300
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On Thu, 2012-06-07 at 14:21 +0200, Giovanni Malfara' wrote:
> Hi all,
>=20
> I need to verify that the UBI image once it has been written on the UBI
> volume.
> So I try to extract the content with the "dd" tool from the UBI bolume
> and I calculate the checksum to be compared with the one of the original
> UBI image.
>=20
> My question is: is it always true? If I extract the content of the UBI
> volume at any time (the fileystem is mounted read-only) , will the
> checksum always the same? Will the data move from a PEB that has
> bit-flips to a new one cause a difference in checksum?

Yes, if you read the UBI volume (/dev/ubiX_Y), and it is R/O, the CRC
should be the same all the time.

--=20
Best Regards,
Artem Bityutskiy

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