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From: Matthieu CASTET <matthieu.castet@parrot.com>
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Subject: Re: ubifs : corruption after power cut test
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Artem Bityutskiy a écrit :
> On Wed, 2010-07-28 at 09:40 +0200, Matthieu CASTET wrote:
>> I manage to reproduce it with the backtrace [1].
> 
> Matthieu, your work-around patch or something very close should
> certainly be applied to the UBIFS tree, but I still would like to find
> out what exactly happened in your setup.
> 
> I see 2 possibilities:
> 
> 1. An error happened and 'ubifs_garbage_collect()' returned while
> c->gc_lnum was -1. But in this case we should have switched to R/O mode,
> and the master node would not be written. But may be for some reasons we
> did not switch to R/O mode, dunno.
> 
> 2. More likely scenario: in 'ubifs_rcvry_gc_commit()' we call
> 'ubifs_garbage_collect_leb()' directly, which can return while
> c->gc_lnum is -1. And we do not handle this.
> 
> Would you please be patient enough to reproduce the issue once again with
> the following patch, which was created against the latest ubifs-2.6.git, but
> you should be easily able to apply it to your tree.
None of these check happen.

only the dump in ubifs_write_master.


Matthieu