From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Wesley W. Terpstra" <wesley@terpstra.ca>
Subject: Re: BUG drivers/md/md.c: data-offset reshape renders array unloadable
Date: Sun, 25 Jan 2015 17:46:20 +0100
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On Sat, Jan 24, 2015 at 11:23 PM, Wesley W. Terpstra <wesley@terpstra.ca> wrote:
>> First, it is obviously the last test in super_1_load that is rejecting
>> the array. The superblock reports more sectors than are calculated, so
>> the check
>>         if (sectors < le64_to_cpu(sb->data_size)) {
>> fails.
>
> Thus, an alternative explanation could be that the the sb->data_size
> was not updated after the reshape completed.

I can confirm that this was the problem.

I manually modified my super block using the attached quick hack.
Thereafter I was able to reassemble the array and fsck everything
successfully.

I will try and see if I can reproduce the problem tomorrow. It's a
pretty nasty bug to have a reshape complete and render your array
unassemblable.

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