Re: Irritating ext2fs corruption

[Theodore Y. Ts'o]

   Date: Tue, 4 Aug 1998 02:10:19 +0200
   From: Jakob Borg <[e-mail]>

   To clarify my original report:

   I create a file (a CD isofs image to be exact). I use it. I remove
   it. I do not get my free space back. I unmount the partition (no
   errors here). Check with a 'mount', yes it is unmounted. I mount
   it. Still no more free space. Unmount and fsck. "deleted inode has
   zero dtime" on one inode, most likely the file in question and
   hundreds of screens of scrolling block numbers when fixing summary
   information. Mount partition, everything is happy again.

Thanks.  This is much more concise and easier to understand.  I wish
more people could file bug reports like this, instead of sending
something laden with emotion invective.  The only thing which is missing
is more details about how you use CD isofs image and what kernel version
you're using.

I just tried to reproduce it under Linux 2.1.112, and I'm not able to.
See the logs below for an example of what I tried to do.  In the first
case, I created a 700 meg file using /dev/zero.  I delete it.  I get the
frees space back.  In the second case, I create a isofs image using
mkisofs; then delete it, and again, I get my free space back.

Is this something you can reliably reproduce on your machine?  If so,
can you try simply creating the image file using mkisofs, then
immediately deleting it, and see if you can reproduce the problem that
way.

						- Ted

P.S.  In my mind at least, we haven't ruled out some kind of wierd
hardware problem yet....

<[e-mail]> {/usr/var/tmp}
1053% df .
Filesystem         1024-blocks  Used Available Capacity Mounted on
/dev/hda3            1903268 1069105   735783     59%   /usr
<[e-mail]> {/usr/var/tmp}
1054% dd if=/dev/zero of=test.img bs=1024k count=700
700+0 records in
700+0 records out
<[e-mail]> {/usr/var/tmp}
1055% df .
Filesystem         1024-blocks  Used Available Capacity Mounted on
/dev/hda3            1903268 1788725    16163     99%   /usr
<[e-mail]> {/usr/var/tmp}
1056% rm test.img
/bin/rm: remove `test.img'? y
<[e-mail]> {/usr/var/tmp}
1057% df .
Filesystem         1024-blocks  Used Available Capacity Mounted on
/dev/hda3            1903268 1069113   735775     59%   /usr

<[e-mail]> {/usr/var/tmp}
1067% df .
Filesystem         1024-blocks  Used Available Capacity Mounted on
/dev/hda3            1903268 1069118   735770     59%   /usr
<[e-mail]> {/usr/var/tmp}
1068% mkisofs -o test.img /usr/src/e2fsprogs/e2fsprogs >& mkisofs.log
<[e-mail]> {/usr/var/tmp}
1069% df .
Filesystem         1024-blocks  Used Available Capacity Mounted on
/dev/hda3            1903268 1086069   718819     60%   /usr
<[e-mail]> {/usr/var/tmp}
1070% rm test.img
/bin/rm: remove `test.img'? y
<[e-mail]> {/usr/var/tmp}
1071% df .
Filesystem         1024-blocks  Used Available Capacity Mounted on
/dev/hda3            1903268 1069118   735770     59%   /usr