task btrfs-transacti:1089 blocked for more than 120 seconds

[jdfalk]

No further information, it popped up to report a an issue, and it was systemd I submitted.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: systemd 225-1ubuntu9 [modified: usr/share/dbus-1/system-services/org.freedesktop.systemd1.service]
Uname: Linux 4.5.0-040500rc7-generic x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: XFCE
Date: Tue Mar 15 22:14:45 2016
InstallationDate: Installed on 2015-05-10 (311 days ago)
InstallationMedia: Ubuntu-Server 15.04 "Vivid Vervet" - Release amd64 (20150422)
MachineType: Gigabyte Technology Co., Ltd. To be filled by O.E.M.
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.5.0-040500rc7-generic root=UUID=51a981ad-aeb0-4bd7-91c6-2d493155c812 ro rootflags=subvol=@ crashkernel=384M-2G:64M,2G-:128M crashkernel=384M-:128M
SourcePackage: systemd
UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
UpgradeStatus: Upgraded to wily on 2015-10-26 (142 days ago)
dmi.bios.date: 01/06/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: F18i
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: Z77X-D3H
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrF18i:bd01/06/2014:svnGigabyteTechnologyCo.,Ltd.:pnTobefilledbyO.E.M.:pvrTobefilledbyO.E.M.:rvnGigabyteTechnologyCo.,Ltd.:rnZ77X-D3H:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: To be filled by O.E.M.
dmi.product.version: To be filled by O.E.M.
dmi.sys.vendor: Gigabyte Technology Co., Ltd.

[Martin Pitt (pitti)]

There is no symptom or error description in your report at all. Dmesg shows that the btrfs task is hung, but there's still not much to go with.

[Joseph Salisbury (jsalisbury)]

Do you have a way to reproduce this issue, or was it a one time event?

[jdfalk (johnathan-falk)]

Just change this to dupe against: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1555828

The drive mounts, and works perfectly fine if you are using it RO. Otherwise, it states that the cache is invalid, and it needs to build the UUID tree. Which I suspect causes the transactions to lock unable to access the disk.

[Brad Figg (brad-figg)]

This change was made by a bot.

[Hendrik Friedel (henfri)]

Hello,

this could help:
[Chris Murphy]: You can also do a one time clean mount with '-o
clear_cache,space_cache=v2' which will remove the v1 (default) space
cache, and create a v2 cache. Subsequent mount will see the flag for
this feature and always use the v2 cache. It's a totally differently
implementation and shouldn't have this problem.

Source: https://lore.kernel.org<email address hidden>/

Regards,
Hendrik