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From: Richard Weinberger <richard@nod.at>
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To: "Wiedemer, Thorsten (Lawo AG)" <Thorsten.Wiedemer@lawo.com>
Subject: Re: UBI leb_write_unlock NULL pointer Oops (continuation)
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Am 04.02.2014 18:01, schrieb Wiedemer, Thorsten (Lawo AG):
> Hi,
> 
> I made a "hardcore test" with:
> $ while [ 1 ]; do cp <file_of_8kByte_size> tmp/<file_of_8kByte_size.1>; sync; done &
> $ while [ 1 ]; do cp <file_of_8kByte_size> tmp/<file_of_8kByte_size.2>; sync; done &
> $ while [ 1 ]; do cp <file_of_8kByte_size> tmp/<file_of_8kByte_size.3>; sync; done &
> 
> It took about 2-3 hours until I had an error (two times):

This test ran the over night without any error on my imx51 board. :-\

Bill's great analysis showed that it may be a linked list corruption in rw_semaphore.
Thorsten, can you please enable CONFIG_DEBUG_LIST?
Also try whether you can trigger the issue with lock debugging enabled.

Thanks,
//richard