2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

[Piggin, Nick]

Hi,
I have a PIV server with two IDE disks, one used for the filesystem, the
other for swap, external journals, and a backup directory.

All partitions are ext3 data=journal, all but the backup directory have
external journals. Please mail me for more HW info if needed and I apologise
if this has already come up (I did search the archives) or is a "known"
"feature".

I have a script which basically does the following

mount /mnt/backup
tar cvf $FILENAME directory
bzip2 $FILENAME
umount /mnt/backup

Upon remounting and inspection, the resulting bzip2 file is corrupted every
time. Adding a sync after bzip2 corrects the problem.

Thanks
Nick

PS. sorry if this mail turns out bad - I'm at work.

Re: 2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

[Bill Davidsen]

On Thu, 18 Jul 2002, Piggin, Nick wrote:

> I have a PIV server with two IDE disks, one used for the filesystem, the
> other for swap, external journals, and a backup directory.
> 
> All partitions are ext3 data=journal, all but the backup directory have
> external journals. Please mail me for more HW info if needed and I apologise
> if this has already come up (I did search the archives) or is a "known"
> "feature".

Is it related to the external journals? How do you have those set up?

-- 
bill davidsen <davidsen@tmr.com>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.

Re: 2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

[Alan Cox]

On Thu, 2002-07-18 at 07:12, Piggin, Nick wrote:
> mount /mnt/backup
> tar cvf $FILENAME directory
> bzip2 $FILENAME
> umount /mnt/backup
> 
> Upon remounting and inspection, the resulting bzip2 file is corrupted every
> time. Adding a sync after bzip2 corrects the problem.

That sounds like a bug in the core code somewhere since the flush should
have happened automatically on umount. Does 2.4.19 proper show this on
your box (or 2.4.20-rc) ? [I'd suspect yes but would like to be sure]

Re: 2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

[Nick Piggin]

Alan Cox wrote:

>On Thu, 2002-07-18 at 07:12, Piggin, Nick wrote:
>
>>mount /mnt/backup
>>tar cvf $FILENAME directory
>>bzip2 $FILENAME
>>umount /mnt/backup
>>
>>Upon remounting and inspection, the resulting bzip2 file is corrupted every
>>time. Adding a sync after bzip2 corrects the problem.
>>
>
>That sounds like a bug in the core code somewhere since the flush should
>have happened automatically on umount. Does 2.4.19 proper show this on
>your box (or 2.4.20-rc) ? [I'd suspect yes but would like to be sure]
>
>
For those that don't remember, $FILENAME is in /mnt/backup and
it was 100% repeatable (ie. a data corruption bug). Alan,
unfortunately I can't do a lot of testing with the box now. I
might be able to give it a try when 2.4.20 comes out, or someone
else might be able to. Directory was only a meg or two IIRC
so it shouldn't be much hasstle for someone with a spare ext3
partition.

Nick

Re: 2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

[Nick Piggin]

Alan Cox wrote:

>On Thu, 2002-07-18 at 07:12, Piggin, Nick wrote:
>
>>mount /mnt/backup
>>tar cvf $FILENAME directory
>>bzip2 $FILENAME
>>umount /mnt/backup
>>
>>Upon remounting and inspection, the resulting bzip2 file is corrupted every
>>time. Adding a sync after bzip2 corrects the problem.
>>
>
>That sounds like a bug in the core code somewhere since the flush should
>have happened automatically on umount. Does 2.4.19 proper show this on
>your box (or 2.4.20-rc) ? [I'd suspect yes but would like to be sure]
>
>
2.4.20 does indeed show this bug. The following script will trigger it:

#!/bin/sh
mount /mnt/backup
dd if=/dev/urandom of=/mnt/backup/test.bin bs=1024 count=512
bzip2 /mnt/backup/test.bin
umount /mnt/backup

After running:
mount /mnt/backup
bunzip2 /mnt/backup/test.bin.bz2
bunzip2: x is not a bzip2 file.

The file is filled mostly with zeros

Nick

RE: 2.4.19-rc1,2 + ext3 data=journal: data loss on unmount

[Piggin, Nick]

I've only tried rc1 and 2 on this machine and its never worked correctly
with either.

-----Original Message-----
From: Hell.Surfers@cwctv.net [mailto:Hell.Surfers@cwctv.net]
Sent: Thursday, 18 July 2002 4:25 PM
To: Nick.Piggin@cit.act.edu.au
Subject: RE:2.4.19-rc1,2 + ext3 data=journal: data loss on unmount


how long has the problem occurred?

- I found it hard, it was hard to find, ohwell, whatever, nevermind. Kurt
Cobain.

On 	Thu, 18 Jul 2002 16:12:49 +1000 	"Piggin, Nick"
<Nick.Piggin@cit.act.edu.au> wrote: