Re: Xfs_repair segfaults.

Filippo Stenico
2013-05-07T18:21:40Z

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xfs_repair -L -vv -P /dev/mapper/vg0-lv0 does the same kernel panic as my
first report. No use to double info on this.
I'll try xfs_repair -L -vv -P -m 2000 to keep memory consuption at a limit.

On Tue, May 7, 2013 at 3:36 PM, Filippo Stenico
<filippo.stenico@gmail.com>wrote:

>
>
> On Tue, May 7, 2013 at 3:20 PM, Eric Sandeen <sandeen@sandeen.net> wrote:
>
>> On 5/7/13 4:27 AM, Filippo Stenico wrote:
>> > Hello,
>> > this is a start-over to try hard to recover some more data out of my
>> raid5 - lvm - xfs toasted volume.
>> > My goal is either to try the best to get some more data out of the
>> volume, and see if I can reproduce the segfault.
>> > I compiled xfsprogs 3.1.9 from deb-source. I ran a xfs_metarestore to
>> put original metadata on the cloned raid volume i had zeroed the log on
>> before via xfs_repair -L (i figured none of the actual data was modified
>> before as I am just working on metadata.. right?).
>> > Then I ran a mount, checked a dir that I knew it was corrupted, unmount
>> and try an xfs_repair (commands.txt attached for details)
>> > I went home to sleep, but at morning I found out that kernel paniced
>> due "out of memory and no killable process".
>> > I ran repair without -P... Should I try now disabling inode prefetch?
>> > Attached are also output of "free" and "top" at time of panic, as well
>> as the output of xfs_repair and strace attached to it. Dont think gdb
>> symbols would help here....
>> >
>>
>> >
>>
>> Ho hum, well, no segfault this time, just an out of memory error?
>>
> That's right....
>
>> No real way to know where it went from the available data I think.
>>
>> A few things:
>>
>> > root@ws1000:~# mount /dev/mapper/vg0-lv0 /raid0/data/
>> > mount: Structure needs cleaning
>>
>> mount failed? Now's the time to look at dmesg to see why.
>>
>
> From attached logs it seems to be:
>>
>> > XFS internal error xlog_valid_rec_header(1) at line 3466 of file
>> [...2.6.32...]/fs/xfs/xfs_log_recover.c
>> > XFS: log mount/recovery failed: error 117
>>
>> > root@ws1000:~# mount
>>
>> <no raid0 mounted>
>>
>> > root@ws1000:~# mount /dev/mapper/vg0-lv0 /raid0/data/
>> > root@ws1000:~# mount | grep raid0
>> > /dev/mapper/vg0-lv0 on /raid0/data type xfs (rw,relatime,attr2,noquota)
>>
>> Uh, now it worked, with no other steps in between? That's a little odd.
>>
> Looks odd to me too. But i just copied the commands issued as they where
> on my console... so yes, nothing in between.
>
>> It found a clean log this time:
>>
>> > XFS mounting filesystem dm-1
>> > Ending clean XFS mount for filesystem: dm-1
>>
>> which is unexpected.
>>
>> So the memory consumption might be a bug but there's not enough info to
>> go on here.
>>
>> > PS. Let me know if you wish reports like this one on list.
>>
>> worth reporting, but I'm not sure what we can do with it.
>> Your storage is in pretty bad shape, and xfs_repair can't make something
>> out
>> of nothing.
>>
>> -Eric
>>
>
> I still got back around 6TB out of 7.2 TB of total data stored, so this
> tells xfs is reliable even when major faults occur...
>
> Thanks anyways, I am trying with a "-L" repair, at this step I expect
> another fail (due out of memory or something, as it happened last time)
> then I will try with "xfs_repair -L -vv -P" and I expect to see that
> segfault again.
>
> Will report next steps, maybe something interesting for you will pop up...
> for me is not a waste of time, since this last try is worth being made.
>
> --
> F

--
F

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