btrfs scrub leads to an readonly filesystem

[Ralf Koelmel]

During an automatic btrfs balance (triggered through an btrfs maintenance timer) there happens a Enospace error.
The next automatic "btrfs balance" step leads afterwards to an kernel error (BTRFS: Transaction aborted (error -28)) and a readonly filesystem.
The system must be rebooted to get a writable filesystem. A scrub doesn't show any erros.
After canceling the paused balance a new manual full balance could be successfully executed.
In the attached syslog file there are the extract of the balance process with the kernel stack trace of a 5.15.0-72-generic kernel.
I've seen on other systems (with former kernels of Ubuntu 22.04 LTS) these problems with readonly filesystems after btrfs balancing.
---
ProblemType: Bug
AlsaDevices:
 total 0
 crw-rw---- 1 root audio 116, 1 Jun 15 09:59 seq
 crw-rw---- 1 root audio 116, 33 Jun 15 09:59 timer
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CRDA: N/A
CasperMD5CheckResult: pass
DistroRelease: Ubuntu 22.04
InstallationDate: Installed on 2022-10-12 (246 days ago)
InstallationMedia: Ubuntu-Server 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220809)
IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig'
MachineType: Supermicro Super Server
Package: linux (not installed)
PciMultimedia:

ProcFB: 0 astdrmfb
ProcKernelCmdLine: BOOT_IMAGE=/@/.snapshots/1/snapshot/vmlinuz-5.15.0-73-generic root=/dev/mapper/system-root2 ro rootflags=subvol=@/.snapshots/1/snapshot console=ttyS1,115200 retbleed=off console=tty0 net.ifnames=0 biosdevname=0 init_on_alloc=0 init_on_free=0 cgroup_enable=memory swapaccount=1 showopts splash crashkernel=512M-:256M vt.handoff=7
ProcVersionSignature: Ubuntu 5.15.0-73.80-generic 5.15.98
RelatedPackageVersions:
 linux-restricted-modules-5.15.0-73-generic N/A
 linux-backports-modules-5.15.0-73-generic N/A
 linux-firmware 20220329.git681281e4-0ubuntu3.13
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
Tags: jammy uec-images
Uname: Linux 5.15.0-73-generic x86_64
UnreportableReason: This report is about a package that is not installed.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: N/A
_MarkForUpload: False
dmi.bios.date: 05/18/2015
dmi.bios.release: 5.6
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1.0b
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: X10SRW-F
dmi.board.vendor: Supermicro
dmi.board.version: 1.01
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 17
dmi.chassis.vendor: Supermicro
dmi.chassis.version: 0123456789
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1.0b:bd05/18/2015:br5.6:svnSupermicro:pnSuperServer:pvr0123456789:rvnSupermicro:rnX10SRW-F:rvr1.01:cvnSupermicro:ct17:cvr0123456789:skuTobefilledbyO.E.M.:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: Super Server
dmi.product.sku: To be filled by O.E.M.
dmi.product.version: 0123456789
dmi.sys.vendor: Supermicro

[Ralf Koelmel (koralle70)]

The attached file is not shown with line breaks.
Therefore here the contenct of the syslog extract:

Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Before balance of /boot
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Data, single: total=1.48GiB, used=1.08GiB
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: System, DUP: total=32.00MiB, used=16.00KiB
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Metadata, DUP: total=168.00MiB, used=1.69MiB
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: GlobalReserve, single: total=3.25MiB, used=0.00B
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Filesystem Size Used Avail Use% Mounted on
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: /dev/mapper/system-boot2 2.2G 1.2G 567M 68% /boot
Jun 1 14:00:15 compute3 kernel: [1126099.579411] BTRFS info (device dm-6): balance: start -dusage=0
Jun 1 14:00:15 compute3 kernel: [1126099.579440] BTRFS info (device dm-6): balance: ended with status: 0
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Done, had to relocate 0 out of 11 chunks
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: getting lock took 0.000003 seconds
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: executing btrfs
Jun 1 14:00:15 compute3 kernel: [1126099.646071] BTRFS info (device dm-6): balance: start -dusage=1
Jun 1 14:00:15 compute3 kernel: [1126099.646100] BTRFS info (device dm-6): balance: ended with status: 0
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Dumping filters: flags 0x1, state 0x0, force is off
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: DATA (flags 0x2): balancing, usage=1
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Done, had to relocate 0 out of 11 chunks
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: getting lock took 0.000003 seconds
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: executing btrfs
Jun 1 14:00:15 compute3 kernel: [1126099.717875] BTRFS info (device dm-6): balance: start -dusage=5
Jun 1 14:00:15 compute3 kernel: [1126099.717903] BTRFS info (device dm-6): balance: ended with status: 0
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Dumping filters: flags 0x1, state 0x0, force is off
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: DATA (flags 0x2): balancing, usage=5
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Done, had to relocate 0 out of 11 chunks
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: getting lock took 0.000002 seconds
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: executing btrfs
Jun 1 14:00:15 compute3 kernel: [1126099.784554] BTRFS info (device dm-6): balance: start -dusage=10
Jun 1 14:00:15 compute3 kernel: [1126099.784583] BTRFS info (device dm-6): balance: ended with status: 0
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Dumping filters: flags 0x1, state 0x0, force is off
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: DATA (flags 0x2): balancing, usage=10
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: Done, had to relocate 0 out of 11 chunks
Jun 1 14:00:15 compute3 btrfs-balance.sh[3559230]: flock: getting lock took 0.000002 seconds
Jun 1 14:00:15 compute3 btrfs-...

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 2023983

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

apport information

[Ralf Koelmel (koralle70)]

The logs from "apport-collect" doesn't contain specific bug related infos, because the bug was happening earlier before booting the latest kernel.