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Subject: Re: UBIFS reboots issue
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Boaz Ben-David <boaz.bd@wellsense-tech.com>
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Date: Wed, 22 Dec 2010 22:20:45 +0200
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On Wed, 2010-12-22 at 16:36 +0200, Boaz Ben-David wrote:
> Hi all,
> 
> We have an embedded system using a Samsung 2GB MLC NAND and are using
> UBIFS as the file system on it.
> I have a question regarding UBIFS and hard reboots.
> After some work with the flash (doing reads and writes to it), some
> times one of our partitions would fail to mount.
> I suspected this has something to do with a reboot which happens during
> a write to the flash.
> In order to test this I created a simple script which copies a file from
> to the partition, syncs, then deletes it and does this repeatedly until 
> a hard reboot occurs (using the watch dog to cause the boot).
> This process repeats itself until the partition fails to mount.
> When I performed the test mentioned above, after about 3-4 times the
> partition would fail.
> I am not sure if this behaviour is normal or not.
> Did someone encounter similiar behaviour?

Just curious, did you see this:

http://linux-mtd.infradead.org/faq/ubifs.html#L_ubifs_mlc

I do not think you can just use UBI/UBIFS on MLC as is, you'd need to
make sure MLC-specific behavior is handled properly.

-- 
Best Regards,
Artem Bityutskiy (Битюцкий Артём)