qemu-KVM guest OS occurs many ext3-fs errors after multiple forced shutdown

[benjamin_zb]

Hi:
I met some filesysterm errors in a sles guest on KVM. My system environment is:
HOST:
   suse 10, the kernel version is 2.6.32.43
   Qemu-KVM 1.2
   Libvirt 1.0
guest OS:
   suse 10, the kernel version is 2.6.32.43
VMs use a qcow2 disk.

Description of problem:
I have 20+ VMs with qcow2 disk, these VMs have been forced to shut down by
"virsh destroy" many times during and after VM installation.
When these vm reboot,dmesg show a ext3-fs mount error occurred on /usr/local
partion /dev/vda3:
    EXT3-fs warning: mounting fs with errors, running e2fsck is recommendedand
when I wrote into partion /dev/vda3,some errors occurred in dmesg:
1.error (device vda3): ext3_free_blocks: Freeing blocks not in datazone - block
= 1869619311, count = 1error (device vda3): ext3_free_blocks_sb: bit already
cleared for block 2178152error (device vda3): ext3_readdir: bad entry in
directory #1083501:
2.[347470.661893] attempt to access beyond end of device[347470.661896] vda3:
rw=0, want=6870892952, limit=41945715[347470.661897] EXT3-fs error (device
vda3): ext3_free_branches: Read failure, inode=1083508, block=858861618
3.EXT3-fs error (device vda3): ext3_new_block: block(4295028581) >= blocks
count(-1) - block_group = 1, es == ffff88021b6c7400

I suspect this fs-error is caused by multiple forced shutdown, but I can't
reproduce this bug now.

So if someone else encountered the same bugs(or fs errors) with me, and what the reasons leads to these fs errors, is the qemu or KVM or just my "rough" cmd.

Thanks in Advance
Regards
Ben

Steps to Reproduce:
I can't reproduce this bug now.

additional:
1.multiple forced shutdown during and after the vm installing
2.vm with qcow2 disk
3.different vm dmesg different errors in above error list(1/2/3)

[Stefan Hajnoczi (stefanha)]

On Tue, Nov 26, 2013 at 01:59:41AM -0000, benjamin_zb wrote:
> I met some filesysterm errors in a sles guest on KVM. My system environment is:
> HOST:
>    suse 10, the kernel version is 2.6.32.43
>    Qemu-KVM 1.2
>    Libvirt 1.0
> guest OS:
>    suse 10, the kernel version is 2.6.32.43
> VMs use a qcow2 disk.
>
> Description of problem:
> I have 20+ VMs with qcow2 disk, these VMs have been forced to shut down by
> "virsh destroy" many times during and after VM installation.
> When these vm reboot,dmesg show a ext3-fs mount error occurred on /usr/local
> partion /dev/vda3:
>     EXT3-fs warning: mounting fs with errors, running e2fsck is recommendedand
> when I wrote into partion /dev/vda3,some errors occurred in dmesg:
> 1.error (device vda3): ext3_free_blocks: Freeing blocks not in datazone - block
> = 1869619311, count = 1error (device vda3): ext3_free_blocks_sb: bit already
> cleared for block 2178152error (device vda3): ext3_readdir: bad entry in
> directory #1083501:
> 2.[347470.661893] attempt to access beyond end of device[347470.661896] vda3:
> rw=0, want=6870892952, limit=41945715[347470.661897] EXT3-fs error (device
> vda3): ext3_free_branches: Read failure, inode=1083508, block=858861618
> 3.EXT3-fs error (device vda3): ext3_new_block: block(4295028581) >= blocks
> count(-1) - block_group = 1, es == ffff88021b6c7400
>
> I suspect this fs-error is caused by multiple forced shutdown, but I can't
> reproduce this bug now.
>
> Could anyone has an idea or suggestion to help me?

What are the mount options for this ext3 file system?

In particular, make sure the barrier=1 option is set.

From linux/Documentation/filesystems/ext3.txt:

  Write barriers enforce proper on-disk ordering of journal commits,
  making volatile disk write caches safe to use, at some performance
  penalty.

Stefan

[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]