btrfsck segmentation fault

btrfsck segmentation fault

[André Goddard Rosa]

Hello,

     when trying to btrfsck my filesystem, I got the following error:

# btrfsck /dev/sda7
parent transid verify failed on 13785038848 wanted 45848 found 45839
Segmentation fault

    Crash occurs at extent-tree.c:find_first_block_group when it gets:

                leaf =3D path->nodes[0];

    after that btrfs_header_nritems dereferences the leaf unconditional=
ly:

        struct btrfs_header *h =3D (struct btrfs_header *)leaf->data;

    Any thoughts on how to make it succeed?

Thank you,
Andr=E9
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" =
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

btrfsck segmentation fault

[Andrew Schretter]

I have a 10TB btrfs filesystem over iSCSI that is currently unmountable.  I'm
currently running Fedora 13 with a recent Fedora 14 kernel (2.6.35.9-64.fc14.i686.PAE)
and the system hung with messages like :

parent transid verify failed on 5937615339520 wanted 48547 found 48542

I've rebooted and and am attempting to recover with btrfsck from the btrfs-progs-unstable
git tree, but it is segfaulting after finding a superblock and listing out 3 of the
"parent transid" messages.  Anyone have any ideas?

I tried btrfsck /dev/sdb, btrfsck -s 1 /dev/sdb, and btrfsck -s 2 /dev/sdb with the
same result for each.  The btrfsck binary I compiled does work on a small (800MB) test
btrfs file system.  I suspect it may be due to the size of the filesystem I am trying
to repair.

Running btrfsck with gdb returns :
#0  find_first_block_group (root=0x8067178, path=0x80677f8, key=0xbffff24b) at extent-tree.c:3028
#1  0x08055603 in btrfs_read_block_groups (root=0x8067178) at extent-tree.c:3072
#2  0x08053009 in open_ctree_fd (fp=7, path=0xbffff63a "/dev/sdb", sb_bytenr=<value optimized out>, writes=0) at disk-io.c:760
#3  0x080530e8 in open_ctree (filename=0xbffff63a "/dev/sdb", sb_bytenr=0, writes=0) at disk-io.c:587
#4  0x0804d3fc in main (ac=<value optimized out>, av=Cannot access memory at address 0x4

In any event, recovering the data would be nice and any ideas to do so would be appreciated.

-- 

Andrew Schretter
Systems Programmer, Duke University
Dept. of Mathematics (919) 660-2866

Re: btrfsck segmentation fault

[cwillu]

On Fri, Jan 7, 2011 at 3:15 PM, Andrew Schretter <schrett@math.duke.edu=
> wrote:
> I have a 10TB btrfs filesystem over iSCSI that is currently unmountab=
le. =A0I'm
> currently running Fedora 13 with a recent Fedora 14 kernel (2.6.35.9-=
64.fc14.i686.PAE)
> and the system hung with messages like :
>
> parent transid verify failed on 5937615339520 wanted 48547 found 4854=
2
>
> I've rebooted and and am attempting to recover with btrfsck from the =
btrfs-progs-unstable
> git tree, but it is segfaulting after finding a superblock and listin=
g out 3 of the
> "parent transid" messages. =A0Anyone have any ideas?
>
> I tried btrfsck /dev/sdb, btrfsck -s 1 /dev/sdb, and btrfsck -s 2 /de=
v/sdb with the
> same result for each. =A0The btrfsck binary I compiled does work on a=
 small (800MB) test
> btrfs file system. =A0I suspect it may be due to the size of the file=
system I am trying
> to repair.

Segfaulting is what the current btrfsck does when it finds a problem;
it doesn't try to fix anything yet.
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" =
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: btrfsck segmentation fault

[Fajar A. Nugraha]

On Sat, Jan 8, 2011 at 5:29 AM, cwillu <cwillu@cwillu.com> wrote:
> On Fri, Jan 7, 2011 at 3:15 PM, Andrew Schretter <schrett@math.duke.e=
du> wrote:
>> I have a 10TB btrfs filesystem over iSCSI that is currently unmounta=
ble. =A0I'm
>> currently running Fedora 13 with a recent Fedora 14 kernel (2.6.35.9=
-64.fc14.i686.PAE)
>> and the system hung with messages like :
>>
>> parent transid verify failed on 5937615339520 wanted 48547 found 485=
42
>>
>> I've rebooted and and am attempting to recover with btrfsck from the=
 btrfs-progs-unstable
>> git tree, but it is segfaulting after finding a superblock and listi=
ng out 3 of the
>> "parent transid" messages. =A0Anyone have any ideas?
>>
>> I tried btrfsck /dev/sdb, btrfsck -s 1 /dev/sdb, and btrfsck -s 2 /d=
ev/sdb with the
>> same result for each. =A0The btrfsck binary I compiled does work on =
a small (800MB) test
>> btrfs file system. =A0I suspect it may be due to the size of the fil=
esystem I am trying
>> to repair.
>
> Segfaulting is what the current btrfsck does when it finds a problem;
> it doesn't try to fix anything yet.

Is there something we can do to fix this particular problem (e.g.
editing the metadata manually to use older transaction group), or is
this one of those forhet-in-you're-screwed kind of thing?

--=20
=46ajar
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" =
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: btrfsck segmentation fault

[Justin Chudgar]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I've got the same problem. That is, I have a 2.6.35 btrfs volume that
segfaults and causes a kernel oops upon attempts to mount it. There is
some data on there that was not covered by the daily backup. Though it
is not the end of the world, I'd like to recover it if possible. If
there are absolutely no recovery options, a note on the wiki about
which failures are nonrecoverable might be good.

Thanks for the continuous improvements.

*Justin Chudgar* - Weed, CA 96094

On 01/08/2011 03:42 AM, Fajar A. Nugraha wrote:
> On Sat, Jan 8, 2011 at 5:29 AM, cwillu <cwillu@cwillu.com> wrote:
>> On Fri, Jan 7, 2011 at 3:15 PM, Andrew Schretter
<schrett@math.duke.edu> wrote:
>>> I have a 10TB btrfs filesystem over iSCSI that is currently
unmountable. I'm
>>> currently running Fedora 13 with a recent Fedora 14 kernel
(2.6.35.9-64.fc14.i686.PAE)
>>> and the system hung with messages like :
>>>
>>> parent transid verify failed on 5937615339520 wanted 48547 found 48542
>>>
>>> I've rebooted and and am attempting to recover with btrfsck from the
btrfs-progs-unstable
>>> git tree, but it is segfaulting after finding a superblock and
listing out 3 of the
>>> "parent transid" messages. Anyone have any ideas?
>>>
>>> I tried btrfsck /dev/sdb, btrfsck -s 1 /dev/sdb, and btrfsck -s 2
/dev/sdb with the
>>> same result for each. The btrfsck binary I compiled does work on a
small (800MB) test
>>> btrfs file system. I suspect it may be due to the size of the
filesystem I am trying
>>> to repair.
>> Segfaulting is what the current btrfsck does when it finds a problem;
>> it doesn't try to fix anything yet.
> Is there something we can do to fix this particular problem (e.g.
> editing the metadata manually to use older transaction group), or is
> this one of those forhet-in-you're-screwed kind of thing?
>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAk0pC0kACgkQUl5UaPAPOwJrMACdFGRSKrw4H56mlG26Tys4hYL/
iiYAn1YNOoUaUvSJz7TB+IwX17V9XfiX
=8vhU
-----END PGP SIGNATURE-----