THx for your hints!
> Your problem could be due to a block layer bug that's been discovered.
> It should be fixed in 4.19.8+
> https://lwn.net/Articles/774440/
I looked into the article, and it mentiones, that the bug occurs, when
no IO scheduler is used, which is not the case for me. So, I would rule
this out.
> 'btrfs insp dump-t -b 448888832 <dev>'
>
> and remove file names before posting it; this might help a dev sort
> out what the problem is.
Have done this, though no file names appear there. this is the output:
btrfs inspect-internal dump-tree -b 448888832 /dev/md42
btrfs-progs v4.19.1
leaf 448888832 items 29 free space 1298 generation 68768 owner CSUM_TREE
leaf 448888832 flags 0x1(WRITTEN) backref revision 1
fs uuid 8c6746f0-944a-45c5-90f3-622724d15998
chunk uuid 7fdb3778-4545-405e-84a9-fc3675e913e5
item 0 key (EXTENT_CSUM EXTENT_CSUM 273782669312) itemoff 15787
itemsize 496
range start 273782669312 end 273783177216 length 507904
item 1 key (EXTENT_CSUM EXTENT_CSUM 273783177216) itemoff 15783
itemsize 4
range start 273783177216 end 273783181312 length 4096
item 2 key (EXTENT_CSUM EXTENT_CSUM 273783181312) itemoff 15007
itemsize 776
range start 273783181312 end 273783975936 length 794624
item 3 key (EXTENT_CSUM EXTENT_CSUM 273783975936) itemoff 15003
itemsize 4
range start 273783975936 end 273783980032 length 4096
item 4 key (EXTENT_CSUM EXTENT_CSUM 273783980032) itemoff 10575
itemsize 4428
range start 273783980032 end 273788514304 length 4534272
item 5 key (EXTENT_CSUM EXTENT_CSUM 273788514304) itemoff 5599
itemsize 4976
range start 273788514304 end 273793609728 length 5095424
item 6 key (EXTENT_CSUM EXTENT_CSUM 273793871872) itemoff 5299
itemsize 300
range start 273793871872 end 273794179072 length 307200
item 7 key (EXTENT_CSUM EXTENT_CSUM 273794195456) itemoff 5291
itemsize 8
range start 273794195456 end 273794203648 length 8192
item 8 key (EXTENT_CSUM EXTENT_CSUM 273794203648) itemoff 5099
itemsize 192
range start 273794203648 end 273794400256 length 196608
item 9 key (EXTENT_CSUM EXTENT_CSUM 273794400256) itemoff 4791
itemsize 308
range start 273794400256 end 273794715648 length 315392
item 10 key (EXTENT_CSUM EXTENT_CSUM 273794715648) itemoff 4779
itemsize 12
range start 273794715648 end 273794727936 length 12288
item 11 key (EXTENT_CSUM EXTENT_CSUM 273794990080) itemoff 4683
itemsize 96
range start 273794990080 end 273795088384 length 98304
item 12 key (EXTENT_CSUM EXTENT_CSUM 273795088384) itemoff 4587
itemsize 96
range start 273795088384 end 273795186688 length 98304
item 13 key (EXTENT_CSUM EXTENT_CSUM 273795448832) itemoff 4571
itemsize 16
range start 273795448832 end 273795465216 length 16384
item 14 key (EXTENT_CSUM EXTENT_CSUM 273795465216) itemoff 4551
itemsize 20
range start 273795465216 end 273795485696 length 20480
item 15 key (EXTENT_CSUM EXTENT_CSUM 273795485696) itemoff 4523
itemsize 28
range start 273795485696 end 273795514368 length 28672
item 16 key (EXTENT_CSUM EXTENT_CSUM 273795514368) itemoff 4427
itemsize 96
range start 273795514368 end 273795612672 length 98304
item 17 key (EXTENT_CSUM EXTENT_CSUM 273795612672) itemoff 4315
itemsize 112
range start 273795612672 end 273795727360 length 114688
item 18 key (EXTENT_CSUM EXTENT_CSUM 273795727360) itemoff 4299
itemsize 16
range start 273795727360 end 273795743744 length 16384
item 19 key (EXTENT_CSUM EXTENT_CSUM 273795743744) itemoff 4283
itemsize 16
range start 273795743744 end 273795760128 length 16384
item 20 key (EXTENT_CSUM EXTENT_CSUM 273795760128) itemoff 4267
itemsize 16
range start 273795760128 end 273795776512 length 16384
item 21 key (EXTENT_CSUM EXTENT_CSUM 273796366336) itemoff 4015
itemsize 252
range start 273796366336 end 273796624384 length 258048
item 22 key (EXTENT_CSUM EXTENT_CSUM 273797410816) itemoff 3543
itemsize 472
range start 273797410816 end 273797894144 length 483328
item 23 key (EXTENT_CSUM EXTENT_CSUM 273798201344) itemoff 2931
itemsize 612
range start 273798201344 end 273798828032 length 626688
item 24 key (EXTENT_CSUM EXTENT_CSUM 273798828032) itemoff 2315
itemsize 616
range start 273798828032 end 273799458816 length 630784
item 25 key (EXTENT_CSUM EXTENT_CSUM 273799720960) itemoff 2255
itemsize 60
range start 273799720960 end 273799782400 length 61440
item 26 key (EXTENT_CSUM EXTENT_CSUM 273799782400) itemoff 2199
itemsize 56
range start 273799782400 end 273799839744 length 57344
item 27 key (EXTENT_CSUM EXTENT_CSUM 273799839744) itemoff 2139
itemsize 60
range start 273799839744 end 273799901184 length 61440
item 28 key (EXTENT_CSUM EXTENT_CSUM 273799901184) itemoff 2023
itemsize 116
range start 273799901184 end 273800019968 length 118784
Hope, this enables someone to help me recover my stuff.
BR, CHristian
