Arch Linux

JJK

Member

Registered: 2013-10-24

Posts: 56

BTRFS corrupt checksum: "found E4E3BDB6 wanted 00000000"

Hello,

Recently arch would not boot because the btrfs partition (/dev/sda5) was corrupt. I managed to get the partition to mount again by booting up a live cd and running:

# btrfs rescue chunk-recover /dev/sda5
# btrfs rescue super-recover /dev/sda5

That fixed the issue for a while, but the next day it was broken again. I then only ran the super recover and it was up and running again.
However, currently btrfs check still gives a corrupt checksum error.

The logs of several commands I ran:

# btrfs check /dev/sda5

checksum verify failed on 11599872 found E4E3BDB6 wanted 00000000
checksum verify failed on 11599872 found E4E3BDB6 wanted 00000000
bytenr mismatch, want=11599872, have=0
ERROR: failed to repair root items: Input/output error
Checking filesystem on /dev/sda5
UUID: 7656afa3-2152-466c-827b-915f2897eab5

# btrfs check --repair /dev/sda5

checksum verify failed on 11599872 found E4E3BDB6 wanted 00000000
checksum verify failed on 11599872 found E4E3BDB6 wanted 00000000
bytenr mismatch, want=11599872, have=0
ERROR: failed to repair root items: Input/output error
enabling repair mode
Checking filesystem on /dev/sda5
UUID: 7656afa3-2152-466c-827b-915f2897eab5

# btrfs check --repair --init-csum-tree /dev/sda5

checksum verify failed on 11599872 found E4E3BDB6 wanted 00000000
checksum verify failed on 11599872 found E4E3BDB6 wanted 00000000
bytenr mismatch, want=11599872, have=0
ERROR: checksum tree refilling failed: -5
enabling repair mode
Creating a new CRC tree
Checking filesystem on /dev/sda5
UUID: 7656afa3-2152-466c-827b-915f2897eab5
Reinitialize checksum tree

# sudo btrfs scrub status -R /

scrub status for 7656afa3-2152-466c-827b-915f2897eab5
	scrub started at Wed Apr 18 10:18:27 2018 and was aborted after 00:04:42
	data_extents_scrubbed: 1963137
	tree_extents_scrubbed: 104300
	data_bytes_scrubbed: 87028027392
	tree_bytes_scrubbed: 1708851200
	read_errors: 0
	csum_errors: 1
	verify_errors: 0
	no_csum: 270657
	csum_discards: 0
	super_errors: 0
	malloc_errors: 0
	uncorrectable_errors: 1
	unverified_errors: 0
	corrected_errors: 0
	last_physical: 89237553152

# dmesg | grep -i btrfs

[    1.303741] Btrfs loaded, crc32c=crc32c-intel
[    1.304442] BTRFS: device fsid 7656afa3-2152-466c-827b-915f2897eab5 devid 1 transid 91549 /dev/sda5
[    1.329687] BTRFS info (device sda5): disk space caching is enabled
[    1.329688] BTRFS info (device sda5): has skinny extents
[    1.334829] BTRFS info (device sda5): bdev /dev/sda5 errs: wr 0, rd 0, flush 0, corrupt 292, gen 0
[    1.412509] BTRFS info (device sda5): enabling ssd optimizations
[    1.737606] BTRFS info (device sda5): disk space caching is enabled
[   18.235884] BTRFS error (device sda5): bad tree block start 0 11599872

Some notes on the above output:
1. The btrfs check commands were run from a live cd.
2. It is very interesting that the init-csum-tree flag fails on invalid checksums.
3. The scrub status is from a scrub that was not finished, however, the number of errors and uncorrectable errors is exactly the same as the output of the finished one that I ran earlier.

Currently my system is running fine, however that missing checksum is still nagging me, and I do not know if/when it might give up again, maybe for good.

I hope you are able to provide me with some tips on what I might try to fix this issue.

kidalabama

Member

Registered: 2020-07-23

Posts: 1

Re: BTRFS corrupt checksum: "found E4E3BDB6 wanted 00000000"

checksum verify failed on 15497692889088 found E4E3BDB6 wanted 00000000
checksum verify failed on 15497692889088 found E4E3BDB6 wanted 00000000
checksum verify failed on 15497692889088 found E4E3BDB6 wanted 00000000
checksum verify failed on 15497692889088 found E4E3BDB6 wanted 00000000
bytenr mismatch, want=15497692889088, have=0
Couldn't setup extent tree
Couldn't open file system

Last edited by kidalabama (2020-08-05 07:54:10)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,668

Re: BTRFS corrupt checksum: "found E4E3BDB6 wanted 00000000"

Please don't necro bump threads

If you want help looking at a potential issue open a new thread and post more details about what you are trying to do.

Closing.