btrfs check Causes File Corruption

["Longhao.Chen" <Longhao.Chen@outlook.com>]

Hello everyone, I use Btrfs as the file system on my laptop. Yesterday, I was preparing to backup a snapshot to an external hard drive using btrfs send, and the following error occurred:

ERROR: send ioctl failed with -5: Input/Output error

I used btrfs scrub to scan the disk, and the result was:

Error summary:    csum=1

Corrected:      0

Uncorrectable:  1

Unverified:     0

Afterwards, I booted a LiveCD and ran:

btrfs check --init-csum-tree

During the running process, many outputs similar to this appeared:

root 1380 inode 5006723 errors 2001, no inode item, link count wrong unresolved ref dir 1164151 index 1566 namelen 28 name <filename> filetype 1 errors 4, no inode ref

Then I found that the file in the above <filename> had disappeared. At this point, I immediately backed up all the existing files and then used:

btrfs check --repair

btrfs rescue

in an attempt to recover the lost files, but was unsuccessful.

The current issues are:

How do I recover the lost files?

Why does btrfs check --init-csum-tree cause file loss? Is this a bug?

LiveCD information:

Linux ubuntu 6.2.0-26-generic #26~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Jul 13 16:27:29 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

Thank you for your help.