Re: Reoccurring ext3 errors: attempt to access beyond end of device, freeing blocks not in datazone

[Bas van Schaik <bas@tuxes.nl>]

Andreas Dilger wrote:
> On May 21, 2008  00:02 +0200, Bas van Schaik wrote:
>   
>> Theodore Tso wrote:
>>     
>>> 15629775440 / 8 = 0x74736E4A   (or in ascii 'Inst')
>>> 13075964688 / 8 = 0x616C6C62   (or in ascii 'blla')
>>> 15354014352 / 8 = 0x72657552   (or in ascii 'Ruer')
>>>
>>> Converting these numbers to hex:
>>>
>>> 1953721929 = 0x74736E49  (or in ascii 'Jnst')
>>> 1634495585 = 0x616C6C61  (or in ascii 'alla'
>>>  543517044 = 0x20656974  (or in ascii 'tie ')
>>> 1919251793 = 0x72657551  (or in ascii 'Quer')
>>>
>>> Given that it's all ascii, it looks like the indirect block somehow
>>> was overwritten, or was substituted by text.
>>>       
>> Ah, such a lead was exactly what I was looking for, now I at least know
>> where those bogus numbers were coming from. Maybe a very dump question:
>> you seem to have reverse the ascii "translation", why? And shouldn't
>> "Jnst" be "Inst"? Note also that the "translations" seem to resemble
>> each other a little bit: "Jnst" = "Jnst", "alla" looks like "blla" and
>> "Ruer" looks like "Quer". Coincidence?
>>     
>
> Or it is possible you are getting single-bit errors somewhere along
> your IO path, and another single-bit error has resulted in this data
> being written to the wrong block to begin with...
>   
I don't think I understand your statement fully... Do you mean that some
bitflip caused the filesystem to initiate a write to the wrong blocks?

  -- Bas