fs turns readonly after some time

[weirdan]

Note that there are no errors on write operations (chown, cat), and read-after-write check shows the data was 'written' (in fact it wasn't, and it's lost after umount/remount):

root@virtual-debian:.../vdfuse# ./vdfuse -w -f /home/weirdan/.vagrant.d/boxes/base/virtualbox/box-disk1.vmdk /mnt/image
root@virtual-debian:.../vdfuse# mount /mnt/image/Partition2 /mnt/image1
root@virtual-debian:.../vdfuse# chown 501:501 -R /mnt/image1/home/vagrant/.ssh/
root@virtual-debian:.../vdfuse# cat /home/weirdan/.ssh/id_dsa.pub>> /mnt/image1/home/vagrant/.ssh/authorized_keys
root@virtual-debian:/home/weirdan/src/vbox-includes/vdfuse# cat /mnt/image1/home/vagrant/.ssh/authorized_keys
ssh-dss AAAAB3NzaC1kc3MAAACBAKzSjC[...snip...]weirdan@virtual-debian-home

Then wait for some time, like 15-30 seconds

Note that mount for Partition2 shows it's mounted readonly, additional write is also rejected:

root@virtual-debian:.../vdfuse# mount
[...snip...]
/home/weirdan/.vagrant.d/boxes/base/virtualbox/box-disk1.vmdk on /mnt/image type fuse.vdfuse (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other)
/mnt/image/Partition2 on /mnt/image1 type ext4 (ro,relatime,data=ordered)
root@virtual-debian:.../vdfuse# cat /home/weirdan/.ssh/id_dsa.pub>> /mnt/image1/home/vagrant/.ssh/authorized_keys
bash: /mnt/image1/home/vagrant/.ssh/authorized_keys: Read-only file system

dmesg shows (for mount-chown-wait-chown sequence):

[142121.787893] loop: Write error at byte offset 0, length 4096.
[142121.788001] Buffer I/O error on device loop2, logical block 0
[142121.788089] lost page write due to I/O error on loop2
[142121.788170] EXT4-fs (loop2): mounted filesystem with ordered data mode. Opts: (null)
[142150.995598] loop: Write error at byte offset 4429185024, length 4096.
[142150.995709] Buffer I/O error on device loop2, logical block 1081344
[142150.995801] lost page write due to I/O error on loop2
[142150.995807] JBD2: Error -5 detected when updating journal superblock for loop2-8.
[142150.996080] loop: Write error at byte offset 4429189120, length 4096.
[142150.996206] loop: Write error at byte offset 4429193216, length 4096.
[142150.996310] Aborting journal on device loop2-8.
[142150.996467] loop: Write error at byte offset 4429185024, length 4096.
[142150.996565] Buffer I/O error on device loop2, logical block 1081344
[142150.996657] lost page write due to I/O error on loop2
[142150.996665] JBD2: Error -5 detected when updating journal superblock for loop2-8.
[142166.006374] EXT4-fs (loop2): previous I/O error to superblock detected
[142166.006482] loop: Write error at byte offset 0, length 4096.
[142166.006526] Buffer I/O error on device loop2, logical block 0
[142166.006566] lost page write due to I/O error on loop2
[142166.006572] EXT4-fs error (device loop2): __ext4_journal_start_sb:62: Detected aborted journal
[142166.006641] EXT4-fs (loop2): Remounting filesystem read-only
[142166.006682] EXT4-fs (loop2): previous I/O error to superblock detected
[142166.006794] loop: Write error at byte offset 0, length 4096.
[142166.006853] Buffer I/O error on device loop2, logical block 0
[142166.006894] lost page write due to I/O error on loop2

System info: Linux virtual-debian 3.10-3-amd64 #1 SMP Debian 3.10.11-1 (2013-09-10) x86_64 GNU/Linux
Virtualbox version: 4.2.16_Debianr86992
Virtualbox headers: svn r49181
Vdfuse version: d64bd92

[Thorsten-Sick]

Hello weirdan, Thanks for reporting it. At the moment I can not reproduce it. Maybe you can also test which operations exactly triggered the switch to read-only.

[weirdan]

Maybe you can also test which operations exactly triggered the switch to read-only.

Do you have any specific test case in mind? The above is what I figured out on my own. I certainly could do more tests, but I just don't know what would be useful.

One thing I noticed is that .vdi works fine, it's .vmdk that breaks with those symptoms.

[Thorsten-Sick]

I also tried vmdk (with a ubuntu installed in it). It worked. For at least an hour. But my OS is Ubuntu with libfuse-dev 2.9.2 and virtualbox 4.2.16-dfsg-3. I am running it on Ubuntu 13.10. At the moment I have no idea what is broken, how and why....