** Changed in: linux (Ubuntu)
Assignee: Andy Whitcroft (apw) => (unassigned)
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1381968
Title:
Fstrim destroys data on loopback device
Status in linux package in Ubuntu:
Incomplete
Bug description:
I've upgraded Ubuntu Server 12.04 LTS to 14.04 LTS.
The setup contains a loopback device (/dev/loop3) mounted into a
software raid 1 (/dev/md2).
After the weekly cronjob (/etc/cron.weekly/fstrim) ran, I've
discovered that it wiped all data on the loopback device from the
raid.
fstrim-all skips check because the loopback device is part of device mapper
raid.
if [ "${REALDEV#/dev/dm-}" != "$REALDEV" ]; then
echo "device $DEV is on devmapper, skipping TRIM feature check"
Issue can be reproduced on raid setup and plain loopback mount setup!
Here is step-by-step how to reproduce the issue:
1.) create sparse image file
dd of=/sparse-file bs=1k seek=1024000
2.) losetup loopback device
losetup /dev/loop3 /sparse-file
3.) create raid1
mdadm --create /dev/md2 --auto md --level=1 --raid-devices=1 /dev/loop3
4.) create fs
mkfs.ext4 /dev/md2
4.1.) check sparse-file size
ls -lash /sparse-file
5.) mount and copy data
mount /dev/md2 /mnt
copy some random files on /mnt
5.1.) check sparse-file size again
ls -lash /sparse-file -> size indicates it contains the copied data
6.) destroy loopback via fstrim
fstrim -v /mnt
7.) data is wiped
umount /mnt
ls -lash /sparse-file -> size indicates that all data is wiped out!
fsck -v -f /dev/md2 -> will report infinite errors on filesystem
I could not find any similiar bugreport.
Best Regards
Daniel
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1381968/+subscriptions
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
