Filesystem and files getting corrupted

Filesystem and files getting corrupted

[Daniel Hilst Selli]

I'm working on an embedded project based on var-som-am35 from TI. [1]

I experiencing a lot of corruption from files and even the entire 
filesystem... is there any guide on how debug filesystems corruption?

We already tryied vfat and ext3 fs.. changed media, changed machines... 
The filesystem runs on mmc card, or on usb flash drive... There is a 
java aplication running on top of this filesystem, which uses JMS, that 
is very I/O agressive..

Cheers,

Filesystem and files getting corrupted

[María Soler Heredia]

I'm really newbie and I don't know if this may help at all, but I googled
"corruption of the file system debug" and found
http://linux.die.net/man/8/debugfs

Maybe you can give it a try if you haven't already,
Mar?a.
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Filesystem and files getting corrupted

[Manish Katiyar]

On Mon, Jun 24, 2013 at 1:08 PM, Daniel Hilst Selli
<danielhilst@gmail.com> wrote:
> I'm working on an embedded project based on var-som-am35 from TI. [1]
>
> I experiencing a lot of corruption from files and even the entire
> filesystem... is there any guide on how debug filesystems corruption?
>
> We already tryied vfat and ext3 fs.. changed media, changed machines...

If both the filesystems are getting corrupted, there is a high chance
that it doesn't have to do anything with filesystem per se. There may
be some random module which is corrupting incore memory/structures,
and debugging that doesn't involve knowing filesystems specifics. To
find the culprit, you may have to identify the interesting things
related to corruption and narrow it down. Some things that can help
are :-

a) Is the corruption always happening at some particular offset of
page or on some specific filesystem metadata
b) What does the corruption look like, do structures get zeroed or get
filled with some value ? If its some particular address you can try
gdb watchpoints
c) What is the size of corruption. How much garbage is there.
Answering this will give you some hint about the structure which is
overwriting


> The filesystem runs on mmc card, or on usb flash drive... There is a
> java aplication running on top of this filesystem, which uses JMS, that
> is very I/O agressive..
>
> Cheers,
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies



--
Thanks -
Manish

Filesystem and files getting corrupted

[Valdis.Kletnieks at vt.edu]

On Tue, 25 Jun 2013 12:28:15 +0200, meccomaria at gmail.com said:
> I'm really newbie and I don't know if this may help at all, but I googled
> "corruption of the file system debug" and found
> http://linux.die.net/man/8/debugfs

That won't help you debug a filesystem - debugfs is *itself* a pseudo-filesystem
that allows kernel programmers to import/export large amounts of debugging
info from the kernel - it was created because there are some restrictions
in the procfs (for /proc) and sysfs (for /sys) filesystems that make them not
very useful for bulk data.

Most distros mount debugfs at /sys/kernel/debug - so everything under that
is handled by debugfs rather than sysfs.

For Daniel's original question:

> We already tryied vfat and ext3 fs.. changed media, changed machines...
> The filesystem runs on mmc card, or on usb flash drive...

This tends to indicate that the problem is *not* a filesystem issue - you're
just *noticing* corruption of your filesystem by some *other* kernel code.

I'd rebuild the kernel, and turn on every kernel debugging option related to
memory management you can find under the 'Kernel Hacking' menu.  In particular,
you want CONFIG_DEBUG_SLAB and also CONFIG_DEBUG_STACKOVERFLOW.  Also, many
kernel subsystems have debugging code for themselves, you may want to turn
on as many of them as you can.

Also, Manish Katiyar <mkatiyar@gmail.com> had some good suggestions to help
narrow down the problem.
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Filesystem and files getting corrupted

[Peter Teoh]

any kernel debugging always start with dmesg output, please provide a
snapshot of that.   (preferably posting full listing at pastebin.com).

On Tue, Jun 25, 2013 at 4:08 AM, Daniel Hilst Selli
<danielhilst@gmail.com>wrote:

> I'm working on an embedded project based on var-som-am35 from TI. [1]
>
> I experiencing a lot of corruption from files and even the entire
> filesystem... is there any guide on how debug filesystems corruption?
>
> We already tryied vfat and ext3 fs.. changed media, changed machines...
> The filesystem runs on mmc card, or on usb flash drive... There is a
> java aplication running on top of this filesystem, which uses JMS, that
> is very I/O agressive..
>
> Cheers,
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>



-- 
Regards,
Peter Teoh
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Filesystem and files getting corrupted

[Daniel Hilst Selli]

On 07/04/2013 12:24 AM, Peter Teoh wrote:
> any kernel debugging always start with dmesg output, please provide a 
> snapshot of that.   (preferably posting full listing at pastebin.com 
> <http://pastebin.com>).
>
> On Tue, Jun 25, 2013 at 4:08 AM, Daniel Hilst Selli 
> <danielhilst at gmail.com <mailto:danielhilst@gmail.com>> wrote:
>
>     I'm working on an embedded project based on var-som-am35 from TI. [1]
>
>     I experiencing a lot of corruption from files and even the entire
>     filesystem... is there any guide on how debug filesystems corruption?
>
>     We already tryied vfat and ext3 fs.. changed media, changed
>     machines...
>     The filesystem runs on mmc card, or on usb flash drive... There is a
>     java aplication running on top of this filesystem, which uses JMS,
>     that
>     is very I/O agressive..
>
>     Cheers,
>
>     _______________________________________________
>     Kernelnewbies mailing list
>     Kernelnewbies at kernelnewbies.org
>     <mailto:Kernelnewbies@kernelnewbies.org>
>     http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
>
>
>
> -- 
> Regards,
> Peter Teoh 
Was a hardware problem...
dmesg won't show anything .. We know that the file get corrupted because 
why try to exctract the jar file and get an error like (not a valid 
zip/jar file)..

Since we use SoMs, we test the same module(the little board) on another 
hardware (the official development kit) and it works without problems.

Since is not broken, but out of specification.. it works for some time 
then starts to do bad things...

I enabled mmc debug, got a lot of output but no error.. bad CRC or 
something like that.. I think that configuration (since is for embedded 
system) is too silent..

Thanks
Cheers!
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