From: Mickael Chazaux <mickael.chazaux@etictelecom.com>
To: Richard Weinberger <richard.weinberger@gmail.com>
Cc: linux-mtd@lists.infradead.org
Subject: Re: ubifs_check_node: bad CRC
Date: Fri, 23 Aug 2019 11:24:28 +0200 [thread overview]
Message-ID: <5D5FB0CC.3050502@etictelecom.com> (raw)
In-Reply-To: <CAFLxGvzF8iDJG_rTqGwrLdmFsehaLxD4os50_QLZTMjytVQ9Dw@mail.gmail.com>
On 13/08/2019 23:41, Richard Weinberger wrote:
>
>> The problem occured in the field on several devices, and I cannot reproduce it
>> in the lab.
>
> It sounds a bit like a memory corruption.
>
>>> Please also disable compression in UBIFS, then the read back data maybe gives
>>> you a hint what went wrong.
>>
>> In the corrupted node I see data from syslog. This system is a bit different
>> than the others we usually make, as there are more power cuts and more log writes.
>
> Hmm. Power cuts or many writes should not trigger such a corruption.
> I'd expect ECC errors or data structure errors in UBIFS. But not a good ECC
> with bad UBIFS data CRC.
>
> But with only one sample it is almost impossible to figure...
>
Memory corruption as in some kind of buffer overflow or use after free ? or physical
bus errors? Anyway I think I will implement some mitigations at the application level,
(eg. less log messages, recovery by creating a new volume, copy the now-readonly data,
rename the volume) because the haystack just got too big for the needle.
Thank you for your help,
Mickael
--
Mickael Chazaux
Software Engineer
Tel : (33) 476 042 006
Fax : (33) 476 042 001
ETIC TELECOM
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next prev parent reply other threads:[~2019-08-23 9:25 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-29 13:28 ubifs_check_node: bad CRC Mickael Chazaux
2019-07-29 18:16 ` Richard Weinberger
2019-07-30 7:28 ` Mickael Chazaux
2019-08-13 21:41 ` Richard Weinberger
2019-08-23 9:24 ` Mickael Chazaux [this message]
2019-08-25 19:02 ` Richard Weinberger
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