Re: kernel BUG at fs/btrfs/extent-tree.c:8113! (4.1.3 kernel)

[Qu Wenruo <quwenruo@cn.fujitsu.com>]

Marc MERLIN wrote on 2015/08/24 07:10 -0700:
> On Mon, Aug 24, 2015 at 01:11:26PM +0800, Qu Wenruo wrote:
>> So, my last bet will be, using "btrfs-find-root -a" to find the root
>> with highest generation, and use the new root to exec "btrfsck -b
>> <bytenr of highest gen root>".
>
>> The latest btrfs-find-root would output possible tree root by
>> descending order of its generation. You'll find proper bytenr quite
>> easy.
>> But be prepared as "btrfs-find-root -a" will iterate all metadata
>> space, so it will takes a long long time to finish.
>> And until it scanned all the space, it won't output anything.
>
> This is what I got:
>
> myth:~# btrfs-find-root -a /dev/mapper/crypt_sdd1
> Superblock thinks the generation is 39538
> Superblock thinks the level is 1
> Well block 4243456(gen: 3 level: 0) seems good, but generation/level doesn't match, want gen: 39538 level: 1
> Well block 4194304(gen: 2 level: 0) seems good, but generation/level doesn't match, want gen: 39538 level: 1
> myth:~#
>
> Does it mean there is no other block I can/should use?
>
> Thanks,
> Marc
>
Patches sent and CCed to you.

Please try the two patches and see what's new.
This time, I think the output will be much larger.

Thanks,
Qu