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Date: Tue, 18 Jun 2013 10:01:12 +0300
From: Adrian Hunter <adrian.hunter@intel.com>
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To: "Prins Anton (ST-CO/ENG1.1)" <Anton.Prins@nl.bosch.com>
Subject: Re: UBIFS failure & stable page writes
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On 18/06/13 09:31, Prins Anton (ST-CO/ENG1.1) wrote:
> Last night I did do additional tests with create/remove of files in a
> while loop on a synchronous mounted UBIFS. I did NOT get any node 0 or 1
> written over this night, but obvious enough I saw some strange node id in
> the orphan area: 0xdead4ead
> 
> 0xdead4ead Is known to me as SPINLOCK_MAGIC; but no glue why It is in the
> orphan area if node number... Is something known about 0xdead4ead?

I am afraid I have not had time to analyze the effects of the double-free
but it is reasonable to assume that UBIFS may be writing an orphan from a
structure that has been freed and therefore re-used by, for example in this
case, a spinlock.