Hi there,

I'm having bad tree block issues on Linux 5.8.5 since yesterday. I'm not
entirely sure how it happened. Any help is appreciated to try and debug.

Thanks!


Here are some logs:


# uname -a
Linux caska 5.8.5-arch1-1 #1 SMP PREEMPT Thu, 27 Aug 2020 18:53:02 +0000 x86_64 GNU/Linux

# btrfs --version
btrfs-progs v5.7

# cat /dev/kmsg
[..]
 SUBSYSTEM=hid
 DEVICE=+hid:0003:1395:0048.0001
6,1212,55540469834,-;usb 2-1: USB disconnect, device number 5
 SUBSYSTEM=usb
 DEVICE=c189:132
6,1213,55546529788,-;usb 2-1: new SuperSpeed Gen 1 USB device number 6 using xhci_hcd
 SUBSYSTEM=usb
 DEVICE=+usb:2-1
6,1214,55546547041,-;usb 2-1: New USB device found, idVendor=1058, idProduct=25a1, bcdDevice=10.14
 SUBSYSTEM=usb
 DEVICE=c189:133
6,1215,55546547043,-;usb 2-1: New USB device strings: Mfr=2, Product=3, SerialNumber=1
 SUBSYSTEM=usb
 DEVICE=c189:133
6,1216,55546547044,-;usb 2-1: Product: Elements 25A1
 SUBSYSTEM=usb
 DEVICE=c189:133
6,1217,55546547045,-;usb 2-1: Manufacturer: Western Digital
 SUBSYSTEM=usb
 DEVICE=c189:133
6,1218,55546547046,-;usb 2-1: SerialNumber: 575853314543374658314C38
 SUBSYSTEM=usb
 DEVICE=c189:133
6,1219,55546548366,-;usb-storage 2-1:1.0: USB Mass Storage device detected
 SUBSYSTEM=usb
 DEVICE=+usb:2-1:1.0
6,1220,55546548538,-;scsi host3: usb-storage 2-1:1.0
 SUBSYSTEM=scsi
 DEVICE=+scsi:host3
5,1221,55547557024,-;scsi 3:0:0:0: Direct-Access     WD       Elements 25A1    1014 PQ: 0 ANSI: 6
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
5,1222,55547557710,-;sd 3:0:0:0: Attached scsi generic sg1 type 0
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
5,1223,55547558772,-;sd 3:0:0:0: [sdb] Spinning up disk...
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
4,1224,55548569673,c;....ready
5,1225,55551610584,-;sd 3:0:0:0: [sdb] Very big device. Trying to use READ CAPACITY(16).
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
5,1226,55551610752,-;sd 3:0:0:0: [sdb] 7813969920 512-byte logical blocks: (4.00 TB/3.64 TiB)
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
5,1227,55551610756,-;sd 3:0:0:0: [sdb] 4096-byte physical blocks
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
5,1228,55551610971,-;sd 3:0:0:0: [sdb] Write Protect is off
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
7,1229,55551610975,-;sd 3:0:0:0: [sdb] Mode Sense: 47 00 10 08
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
3,1230,55551611224,-;sd 3:0:0:0: [sdb] No Caching mode page found
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
3,1231,55551611232,-;sd 3:0:0:0: [sdb] Assuming drive cache: write through
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0
6,1232,55551829992,-; sdb: sdb1
5,1233,55551831353,-;sd 3:0:0:0: [sdb] Attached SCSI disk
 SUBSYSTEM=scsi
 DEVICE=+scsi:3:0:0:0


# cryptsetup open --type=luks /dev/sdb1 data
Enter passphrase for /dev/sdb1:

# mount -t btrfs -o rw,subvol=/data /dev/mapper/data /data
mount: /data: wrong fs type, bad option, bad superblock on /dev/mapper/data, missing codepage or helper program, or other error.

# file -s /dev/mapper/data
/dev/mapper/data: symbolic link to ../dm-1
# file -s /dev/dm-1
/dev/dm-1: BTRFS Filesystem sectorsize 4096, nodesize 16384, leafsize 16384, UUID=dd439261-afed-4c9e-8685-07d46e46e917, 3829686697984/4000749432832 bytes used, 1 devices

# btrfs fi show
Label: none  uuid: dd439261-afed-4c9e-8685-07d46e46e917
        Total devices 1 FS bytes used 3.48TiB
        devid    1 size 3.64TiB used 3.49TiB path /dev/mapper/data

# btrfs check --readonly /dev/mapper/data
Opening filesystem to check...
checksum verify failed on 3972119019520 found 000000FC wanted FFFFFFEE
checksum verify failed on 3972119019520 found 00000001 wanted 00000055
checksum verify failed on 3972119019520 found 00000001 wanted 00000055
bad tree block 3972119019520, bytenr mismatch, want=3972119019520, have=5982236876204203511
Couldn't read tree root
ERROR: cannot open file system

# btrfs rescue chunk-recover /dev/mapper/data
Scanning: DONE in dev0
No valid btrfs found
open with broken chunk error
Chunk tree recovery failed
btrfs rescue chunk-recover /dev/mapper/data  428.09s user 3162.61s system 9% cpu 10:28:53.27 total

-- 
Maxime “pep” Buquet