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Subject: Re: ubi_eba_init_scan: cannot reserve enough PEBs
From: Artem Bityutskiy <dedekind1@gmail.com>
To: "Matthew L. Creech" <mlcreech@gmail.com>
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Date: Wed, 25 Aug 2010 06:51:03 +0300
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Hi,

On Tue, 2010-08-24 at 18:38 -0400, Matthew L. Creech wrote:
> I applied your patch to 2.6.35 and booted that on the same bad device
> for which I posted a boot log.  But to my surprise, it didn't give any
> errors at all - the boot process completed normally, and it appears to
> be working fine so far.  I had booted the kernel from memory, so I
> pulled the power and let it go through the normal boot process (using
> the 2.6.31 kernel that's built in to the firmware) - that also works
> fine.
> 
> I checked my sanity by trying another bad device, and the same thing
> happened there - booting 2.6.35 somehow "fixed" my problem.
> Unfortunately, this means I can no longer tell what happened to the
> original block you were interested in.  I'll try to dig up another bad
> device, and use your patch with an older kenel version to see what
> happens there.

This is interesting. BTW, if you use 2.6.31, you should in any case
apply patches from the ubifs-v2.6.31 back-port tree, there were some
good fixes.

> Is it at all possible that the error was caused by something at the
> UBI or MTD layer which was fixed between 2.6.34 and 2.6.35, and
> booting up with 2.6.35 "touched" something that made it work again
> even after reverting to an older kernel?  Sounds pretty far-fetched,
> but I don't know how else to explain these suddenly-recovered
> devices...

OK :-)

Artem.