errors reported by btrfs-check

errors reported by btrfs-check

[Jürgen Herrmann]

Hi!

I just did a btrfs check on my laptop's btrfs filesystem while i was
on the usb stick rescue system.

the following errors where reported:
root@mint:/home/mint# btrfs check /dev/mapper/sda3crypt
Checking filesystem on /dev/mapper/sda3crypt
UUID: a914c141-72bf-448b-847f-d64ee82d8b7b
checking extents
checking free space cache
checking fs roots
root 258 inode 3082368 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 258 inode 3082370 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 258 inode 3082371 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 258 inode 3082373 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 258 inode 3082414 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 258 inode 3082415 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 258 inode 3082421 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
root 1387 inode 3082368 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1387 inode 3082370 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1387 inode 3082371 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1387 inode 3082372 errors 100, file extent discount
Found file extent holes:
	start: 8192, len: 4096
	start: 16384, len: 4096
	start: 24576, len: 4096
	start: 32768, len: 4096
	start: 40960, len: 4096
	start: 49152, len: 20480
	start: 73728, len: 4096
	start: 81920, len: 4096
	start: 90112, len: 8192
root 1387 inode 3082373 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1387 inode 3082374 errors 100, file extent discount
Found file extent holes:
	start: 8192, len: 4096
	start: 16384, len: 20480
	start: 40960, len: 12288
	start: 57344, len: 4096
	start: 65536, len: 8192
root 1387 inode 3082380 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 233472
root 1387 inode 3082386 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
root 1387 inode 3082398 errors 100, file extent discount
Found file extent holes:
	start: 20480, len: 16384
root 1387 inode 3082414 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1387 inode 3082415 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1387 inode 3082421 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
root 1391 inode 3082368 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1391 inode 3082370 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1391 inode 3082371 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1391 inode 3082373 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1391 inode 3082386 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
root 1391 inode 3082414 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1391 inode 3082415 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1391 inode 3082421 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
root 1394 inode 3082368 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1394 inode 3082370 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1394 inode 3082371 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1394 inode 3082373 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1394 inode 3082386 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
root 1394 inode 3082414 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1394 inode 3082415 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 8192
root 1394 inode 3082421 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 4096
ERROR: errors found in fs roots
found 469458231296 bytes used, error(s) found
total csum bytes: 451180560
total tree bytes: 4558831616
total fs tree bytes: 3802955776
total extent tree bytes: 245055488
btree space waste bytes: 842802897
file data blocks allocated: 9656815640576
  referenced 929225080832

Scrub completes ok though.

I'm prepared to wipe the fs if needed, more than one backup is ready :)

I wanted to ask here first if I should attempt a repair.

Best regards,
Jürgen
-- 
Jürgen Herrmann
https://t-5.eu
ALbertstraße 2
94327 Bogen

Re: errors reported by btrfs-check

[Chris Murphy]

What version of btrfs-progs?

Re: errors reported by btrfs-check

[Jürgen Herrmann]

4.17.1 compiled from source.

Best regards,
Jürgen

Am 12. Oktober 2018 00:36:26 schrieb Chris Murphy <lists@colorremedies.com>:

> What version of btrfs-progs?


Mit AquaMail Android
https://www.mobisystems.com/aqua-mail

Re: errors reported by btrfs-check

[Qu Wenruo]

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On 2018/10/12 上午4:30, Jürgen Herrmann wrote:
> Hi!
> 
> I just did a btrfs check on my laptop's btrfs filesystem while i was
> on the usb stick rescue system.
> 
> the following errors where reported:
> root@mint:/home/mint# btrfs check /dev/mapper/sda3crypt
> Checking filesystem on /dev/mapper/sda3crypt
> UUID: a914c141-72bf-448b-847f-d64ee82d8b7b
> checking extents
> checking free space cache
> checking fs roots
> root 258 inode 3082368 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 258 inode 3082370 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 258 inode 3082371 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 258 inode 3082373 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 258 inode 3082414 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 258 inode 3082415 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 258 inode 3082421 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> root 1387 inode 3082368 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1387 inode 3082370 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1387 inode 3082371 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1387 inode 3082372 errors 100, file extent discount
> Found file extent holes:
>     start: 8192, len: 4096
>     start: 16384, len: 4096
>     start: 24576, len: 4096
>     start: 32768, len: 4096
>     start: 40960, len: 4096
>     start: 49152, len: 20480
>     start: 73728, len: 4096
>     start: 81920, len: 4096
>     start: 90112, len: 8192
> root 1387 inode 3082373 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1387 inode 3082374 errors 100, file extent discount
> Found file extent holes:
>     start: 8192, len: 4096
>     start: 16384, len: 20480
>     start: 40960, len: 12288
>     start: 57344, len: 4096
>     start: 65536, len: 8192
> root 1387 inode 3082380 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 233472
> root 1387 inode 3082386 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> root 1387 inode 3082398 errors 100, file extent discount
> Found file extent holes:
>     start: 20480, len: 16384
> root 1387 inode 3082414 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1387 inode 3082415 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1387 inode 3082421 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> root 1391 inode 3082368 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1391 inode 3082370 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1391 inode 3082371 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1391 inode 3082373 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1391 inode 3082386 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> root 1391 inode 3082414 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1391 inode 3082415 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1391 inode 3082421 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> root 1394 inode 3082368 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1394 inode 3082370 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1394 inode 3082371 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1394 inode 3082373 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1394 inode 3082386 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> root 1394 inode 3082414 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1394 inode 3082415 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 8192
> root 1394 inode 3082421 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 4096
> ERROR: errors found in fs roots
> found 469458231296 bytes used, error(s) found
> total csum bytes: 451180560
> total tree bytes: 4558831616
> total fs tree bytes: 3802955776
> total extent tree bytes: 245055488
> btree space waste bytes: 842802897
> file data blocks allocated: 9656815640576
>  referenced 929225080832
> 
> Scrub completes ok though.
> 
> I'm prepared to wipe the fs if needed, more than one backup is ready :)

No need. File extent discount is not a big problem.

It only means btrfs lacks some hole file extent to fill the hole.

It can be "fixed" easily by enabling no_holes features:

# btrfstune -n <device>

> 
> I wanted to ask here first if I should attempt a repair.

And of course, btrfs check --repair should be able to fix it.

Thanks,
Qu

> 
> Best regards,
> Jürgen


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Re: errors reported by btrfs-check

[Jürgen Herrmann]

Am 12.10.2018 01:56, schrieb Qu Wenruo:
> On 2018/10/12 上午4:30, Jürgen Herrmann wrote:
>> Hi!
>> 
>> I just did a btrfs check on my laptop's btrfs filesystem while i was
>> on the usb stick rescue system.
>> 
>> the following errors where reported:
>> root@mint:/home/mint# btrfs check /dev/mapper/sda3crypt
>> Checking filesystem on /dev/mapper/sda3crypt
>> UUID: a914c141-72bf-448b-847f-d64ee82d8b7b
>> checking extents
>> checking free space cache
>> checking fs roots
>> root 258 inode 3082368 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 258 inode 3082370 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 258 inode 3082371 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 258 inode 3082373 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 258 inode 3082414 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 258 inode 3082415 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 258 inode 3082421 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> root 1387 inode 3082368 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1387 inode 3082370 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1387 inode 3082371 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1387 inode 3082372 errors 100, file extent discount
>> Found file extent holes:
>>     start: 8192, len: 4096
>>     start: 16384, len: 4096
>>     start: 24576, len: 4096
>>     start: 32768, len: 4096
>>     start: 40960, len: 4096
>>     start: 49152, len: 20480
>>     start: 73728, len: 4096
>>     start: 81920, len: 4096
>>     start: 90112, len: 8192
>> root 1387 inode 3082373 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1387 inode 3082374 errors 100, file extent discount
>> Found file extent holes:
>>     start: 8192, len: 4096
>>     start: 16384, len: 20480
>>     start: 40960, len: 12288
>>     start: 57344, len: 4096
>>     start: 65536, len: 8192
>> root 1387 inode 3082380 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 233472
>> root 1387 inode 3082386 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> root 1387 inode 3082398 errors 100, file extent discount
>> Found file extent holes:
>>     start: 20480, len: 16384
>> root 1387 inode 3082414 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1387 inode 3082415 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1387 inode 3082421 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> root 1391 inode 3082368 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1391 inode 3082370 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1391 inode 3082371 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1391 inode 3082373 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1391 inode 3082386 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> root 1391 inode 3082414 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1391 inode 3082415 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1391 inode 3082421 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> root 1394 inode 3082368 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1394 inode 3082370 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1394 inode 3082371 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1394 inode 3082373 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1394 inode 3082386 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> root 1394 inode 3082414 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1394 inode 3082415 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 8192
>> root 1394 inode 3082421 errors 100, file extent discount
>> Found file extent holes:
>>     start: 0, len: 4096
>> ERROR: errors found in fs roots
>> found 469458231296 bytes used, error(s) found
>> total csum bytes: 451180560
>> total tree bytes: 4558831616
>> total fs tree bytes: 3802955776
>> total extent tree bytes: 245055488
>> btree space waste bytes: 842802897
>> file data blocks allocated: 9656815640576
>>  referenced 929225080832
>> 
>> Scrub completes ok though.
>> 
>> I'm prepared to wipe the fs if needed, more than one backup is ready 
>> :)
> 
> No need. File extent discount is not a big problem.
> 
> It only means btrfs lacks some hole file extent to fill the hole.
> 
> It can be "fixed" easily by enabling no_holes features:
> 
> # btrfstune -n <device>
> 
>> 
>> I wanted to ask here first if I should attempt a repair.
> 
> And of course, btrfs check --repair should be able to fix it.
> 
> Thanks,
> Qu
> 
>> 
>> Best regards,
>> Jürgen

Hi there!

I ran btrfs check --repair on the filesystem. I dont' have this log 
anymore,
as it was then sitting on the repaired fs), which is now dead.
after repairing it I could still mount the fs.

as my btrfs send problem still persists (another thread), I decided to 
run check
again... this time i saved the logs to a different partition as it was 
more
convenient at that time. here's the output:

Checking filesystem on /dev/mapper/sda3c
UUID: a914c141-72bf-448b-847f-d64ee82d8b7b
[1/7] checking root items
Fixed 0 roots.
[2/7] checking extents
No device size related problem found
[3/7] checking free space cache
cache and super generation don't match, space cache will be invalidated
[4/7] checking fs roots
root 1387 inode 3082380 errors 100, file extent discount
Found file extent holes:
	start: 0, len: 233472
ERROR: errors found in fs roots
found 470636822528 bytes used, error(s) found
total csum bytes: 452176524
total tree bytes: 4579753984
total fs tree bytes: 3822665728
total extent tree bytes: 245301248
btree space waste bytes: 847442809
file data blocks allocated: 9670623588352
  referenced 932405829632

I did a repair once again but the error did not go away.

after rebooting the fs is no longer mountable:
mint@mint:/tmp$ sudo /tmp/btrfs check /dev/mapper/sda3c
Opening filesystem to check...
parent transid verify failed on 166475366400 wanted 127054 found 127060
parent transid verify failed on 166475366400 wanted 127054 found 127060
Ignoring transid failure
ERROR: child eb corrupted: parent bytenr=166456229888 item=22 parent 
level=2 child level=0
ERROR: cannot open file system

If anyone wants me to help debugging this issue you will have to respond
fast, because i need my laptop back in working condition and will soon
nuke the fs. after all I will try one more time with a freshly formatted
btrfs partition. if i still get these kinds of errors i will have to 
move back to
the tried and true xfs :/

best regards,
Jürgen
-- 
Jürgen Herrmann
https://t-5.eu
ALbertstraße 2
94327 Bogen

Re: errors reported by btrfs-check

[Qu Wenruo]

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[snip]
> 
> Hi there!
> 
> I ran btrfs check --repair on the filesystem. I dont' have this log
> anymore,
> as it was then sitting on the repaired fs), which is now dead.
> after repairing it I could still mount the fs.
> 
> as my btrfs send problem still persists (another thread), I decided to
> run check
> again... this time i saved the logs to a different partition as it was more
> convenient at that time. here's the output:
> 
> Checking filesystem on /dev/mapper/sda3c
> UUID: a914c141-72bf-448b-847f-d64ee82d8b7b
> [1/7] checking root items
> Fixed 0 roots.
> [2/7] checking extents
> No device size related problem found
> [3/7] checking free space cache
> cache and super generation don't match, space cache will be invalidated
> [4/7] checking fs roots
> root 1387 inode 3082380 errors 100, file extent discount
> Found file extent holes:
>     start: 0, len: 233472
> ERROR: errors found in fs roots
> found 470636822528 bytes used, error(s) found
> total csum bytes: 452176524
> total tree bytes: 4579753984
> total fs tree bytes: 3822665728
> total extent tree bytes: 245301248
> btree space waste bytes: 847442809
> file data blocks allocated: 9670623588352
>  referenced 932405829632
> 
> I did a repair once again but the error did not go away.
> 
> after rebooting the fs is no longer mountable:
> mint@mint:/tmp$ sudo /tmp/btrfs check /dev/mapper/sda3c
> Opening filesystem to check...
> parent transid verify failed on 166475366400 wanted 127054 found 127060
> parent transid verify failed on 166475366400 wanted 127054 found 127060
> Ignoring transid failure
> ERROR: child eb corrupted: parent bytenr=166456229888 item=22 parent
> level=2 child level=0

Please run the following command:

# btrfs ins dump-tree --follow -b 166456229888

It could be caused by the fact that btrfs-progs --repair doesn't handle
log tree well.

If that's the case, "btrfs rescue zero-log" should help.

But anyway, feel free to re-create the fs if zero-log doesn't help.

Thanks,
Qu


> ERROR: cannot open file system
> 
> If anyone wants me to help debugging this issue you will have to respond
> fast, because i need my laptop back in working condition and will soon
> nuke the fs. after all I will try one more time with a freshly formatted
> btrfs partition. if i still get these kinds of errors i will have to
> move back to
> the tried and true xfs :/
> 
> best regards,
> Jürgen


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Re: errors reported by btrfs-check

[Jürgen Herrmann]

Am 12.10.2018 10:19, schrieb Qu Wenruo:

[snip]

> Please run the following command:
> 
> # btrfs ins dump-tree --follow -b 166456229888
> 
> It could be caused by the fact that btrfs-progs --repair doesn't handle
> log tree well.
> 
> If that's the case, "btrfs rescue zero-log" should help.
> 
> But anyway, feel free to re-create the fs if zero-log doesn't help.
> 
> Thanks,
> Qu

First of all, thanks for your help!

Did that:

root@mint:/home/mint# /tmp/btrfs ins dump-tree --follow -b 166456229888 
/dev/mapper/sda3c  > /tmp/btrfs-ins.txt
parent transid verify failed on 166475366400 wanted 127054 found 127060
Ignoring transid failure
WARNING: eb corrupted: parent bytenr 166456229888 slot 22 level 2 child 
bytenr 166475366400 level has 0 expect 1, skipping the slot

The created btrfs-ins.txt is ~300MB in size, so i did not attach that 
here. do you need id? then I can upload it to my owncloud and post a 
link here.

after that i tried to zero the log:
parent transid verify failed on 166475366400 wanted 127054 found 127060
parent transid verify failed on 166475366400 wanted 127054 found 127060
Ignoring transid failure
ERROR: child eb corrupted: parent bytenr=166456229888 item=22 parent 
level=2 child level=0
ERROR: could not open ctree

mounting is still not possible:
[ 2726.355134] BTRFS info (device dm-0): disk space caching is enabled
[ 2726.355138] BTRFS info (device dm-0): has skinny extents
[ 2726.395638] BTRFS error (device dm-0): parent transid verify failed 
on 166475366400 wanted 127054 found 127060
[ 2726.395647] BTRFS error (device dm-0): failed to read block groups: 
-5
[ 2726.451907] BTRFS error (device dm-0): open_ctree failed

Anything left to try?

Best regards,
Jürgen
-- 
Jürgen Herrmann
https://t-5.eu
ALbertstraße 2
94327 Bogen

Re: errors reported by btrfs-check

[Qu Wenruo]

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On 2018/10/12 下午6:35, Jürgen Herrmann wrote:
> Am 12.10.2018 10:19, schrieb Qu Wenruo:
> 
> [snip]
> 
>> Please run the following command:
>>
>> # btrfs ins dump-tree --follow -b 166456229888
>>
>> It could be caused by the fact that btrfs-progs --repair doesn't handle
>> log tree well.
>>
>> If that's the case, "btrfs rescue zero-log" should help.
>>
>> But anyway, feel free to re-create the fs if zero-log doesn't help.
>>
>> Thanks,
>> Qu
> 
> First of all, thanks for your help!
> 
> Did that:
> 
> root@mint:/home/mint# /tmp/btrfs ins dump-tree --follow -b 166456229888
> /dev/mapper/sda3c  > /tmp/btrfs-ins.txt
> parent transid verify failed on 166475366400 wanted 127054 found 127060
> Ignoring transid failure
> WARNING: eb corrupted: parent bytenr 166456229888 slot 22 level 2 child
> bytenr 166475366400 level has 0 expect 1, skipping the slot
> 
> The created btrfs-ins.txt is ~300MB in size, so i did not attach that
> here. do you need id? then I can upload it to my owncloud and post a
> link here.
> 
> after that i tried to zero the log:
> parent transid verify failed on 166475366400 wanted 127054 found 127060
> parent transid verify failed on 166475366400 wanted 127054 found 127060
> Ignoring transid failure
> ERROR: child eb corrupted: parent bytenr=166456229888 item=22 parent
> level=2 child level=0
> ERROR: could not open ctree
> 
> mounting is still not possible:
> [ 2726.355134] BTRFS info (device dm-0): disk space caching is enabled
> [ 2726.355138] BTRFS info (device dm-0): has skinny extents
> [ 2726.395638] BTRFS error (device dm-0): parent transid verify failed
> on 166475366400 wanted 127054 found 127060
> [ 2726.395647] BTRFS error (device dm-0): failed to read block groups: -5

This means the extent tree is corrupted.

This is not a good thing at all.

Please go ahead and recreate the fs.

I'm not sure how is --repair contribute to this bug in current stage.
The biggest problem is, after your first --repair attempt, it doesn't
report any extent tree corruption.

> [ 2726.451907] BTRFS error (device dm-0): open_ctree failed
> 
> Anything left to try?

No, please go ahead to do what you need to.

Thanks,
Qu

> 
> Best regards,
> Jürgen


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