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Subject: Re: Grow UBI device?
From: Artem Bityutskiy <dedekind1@gmail.com>
To: "Gupta, Pekon" <pekon@ti.com>
Date: Thu, 10 Oct 2013 10:42:42 +0300
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On Wed, 2013-10-09 at 11:28 +0000, Gupta, Pekon wrote:
> Yes, during mounting of UBIFS volumes, UBI checks for erase-header
> on first-page of every block. 
> - If it's able to find a valid erase-header, with correct image_seq field,
> then it attaches it to its pool.
> - Otherwise, if the valid erase-header was not found, then it assumes
>  then it ubi will try re-erasing it. And add it to its pool of free-blocks.

I think there is a separate list for blocks with garbage, and if UBI
finds too much of them, it attaches R/O. So if it would find too many
JFFS2 eraseblocks, it would not erase them. But erasing the JFFS2 blocks
from outside of UBI driver would help.

-- 
Best Regards,
Artem Bityutskiy