how to repair or access broken btrfs?

how to repair or access broken btrfs?

[Stefan Priebe - Profihost AG]

Hello,

after a controller firmware bug / failure i've a broken btrfs.

# parent transid verify failed on 181846016 wanted 143404 found 143399

running repair, fsck or zero-log always results in the same failure message:
extent-tree.c:2725: alloc_reserved_tree_block: BUG_ON `ret` triggered,
value -1
.. stack trace ..

Is there an chance to get at least a single file out of the broken fs?

Greets,
Stefan


Complete output:
./btrfs check --repair /dev/mapper/crypt_md0
enabling repair mode
parent transid verify failed on 181846016 wanted 143404 found 143399
parent transid verify failed on 181846016 wanted 143404 found 143399
Ignoring transid failure
Checking filesystem on /dev/mapper/crypt_md0
UUID: d3f9eee9-efbd-4590-858f-27b39d453350
repair mode will force to clear out log tree, are you sure? [y/N]: y
parent transid verify failed on 308183040 wanted 143404 found 143399
parent transid verify failed on 308183040 wanted 143404 found 143399
Ignoring transid failure
parent transid verify failed on 338870272 wanted 143404 found 143399
parent transid verify failed on 338870272 wanted 143404 found 143399
Ignoring transid failure
parent transid verify failed on 12778157178880 wanted 143404 found 143399
parent transid verify failed on 12778157178880 wanted 143404 found 143399
Ignoring transid failure
leaf parent key incorrect 38699008
btrfs unable to find ref byte nr 12778147823616 parent 0 root 2  owner 0
offset 0
parent transid verify failed on 308183040 wanted 143404 found 143399
Ignoring transid failure
leaf parent key incorrect 91766784
extent-tree.c:2725: alloc_reserved_tree_block: BUG_ON `ret` triggered,
value -1
./btrfs[0x415cb3]
./btrfs[0x416ee5]
./btrfs[0x417104]
./btrfs[0x418cea]
./btrfs[0x418f06]
./btrfs(btrfs_alloc_free_block+0x1e4)[0x41b8d0]
./btrfs(__btrfs_cow_block+0xd3)[0x40c5f9]
./btrfs(btrfs_cow_block+0x110)[0x40d03b]
./btrfs(commit_tree_roots+0x53)[0x439a37]
./btrfs(btrfs_commit_transaction+0xf9)[0x439e02]
./btrfs(cmd_check+0x861)[0x46172e]
./btrfs(main+0x163)[0x40b5e9]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)[0x7f44b14fab45]
./btrfs[0x40b0b9]
Aborted

Re: how to repair or access broken btrfs?

[Andrei Borzenkov]

14.11.2017 12:56, Stefan Priebe - Profihost AG пишет:
> Hello,
> 
> after a controller firmware bug / failure i've a broken btrfs.
> 
> # parent transid verify failed on 181846016 wanted 143404 found 143399
> 
> running repair, fsck or zero-log always results in the same failure message:
> extent-tree.c:2725: alloc_reserved_tree_block: BUG_ON `ret` triggered,
> value -1
> .. stack trace ..
> 
> Is there an chance to get at least a single file out of the broken fs?
> 

Did you try "btrfs restore"?

Re: how to repair or access broken btrfs?

[Stefan Priebe - Profihost AG]

Am 14.11.2017 um 18:45 schrieb Andrei Borzenkov:
> 14.11.2017 12:56, Stefan Priebe - Profihost AG пишет:
>> Hello,
>>
>> after a controller firmware bug / failure i've a broken btrfs.
>>
>> # parent transid verify failed on 181846016 wanted 143404 found 143399
>>
>> running repair, fsck or zero-log always results in the same failure message:
>> extent-tree.c:2725: alloc_reserved_tree_block: BUG_ON `ret` triggered,
>> value -1
>> .. stack trace ..
>>
>> Is there an chance to get at least a single file out of the broken fs?
>>
> 
> Did you try "btrfs restore"?

Great that worked for that file. Still wondering why a repair is not
possible.

Greets,
Stefan