df report negative value

[Xu Zhiping <xuzp@yangtze.hku.hk>]

Dear All:
    I am using Woody, with kernel 2.4.20. My df gave strange statistics on 
my disk space.
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ZQS-PC0:/home/xuzp# du -sm /*
3       /bin
5       /boot
1       /cdrom
1       /dev
22      /etc
18914   /home
1       /initrd
12      /lib
1       /mnt
20      /opt
1       /proc
7       /root
3       /sbin
1       /sys
1       /tmp
3621    /usr
1447    /var
ZQS-PC0:/home/xuzp# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/hda1             20972176 -73786976277683455280 17175723360 101% /
/dev/hda2             83888860  19342424  64546436  24% /home
ZQS-PC0:/home/xuzp# cat /etc/fstab 
# /etc/fstab: static file system information.
#
# <file system> <mount point>   <type>  <options>               <dump>  
<pass>
/dev/hda1       /               reiserfs        defaults        0       0
/dev/hda2       /home           reiserfs        defaults        0       0
/dev/hda3       none            swap    sw                      0       0
proc            /proc           proc    defaults                0       0
/dev/fd0        /floppy         auto    user,noauto             0       0
/dev/cdrom      /cdrom          iso9660 ro,user,noauto          0       0
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    Can anyone give me some idea on it? Thanks a lot.


ZP


-- 
---------------------------------------------
 Xu ZhiPing
 Ph.D Candidate
 Office: 3-405
 Tel    : +86-10-627-83814
 Department of Enginnering Mechanics
 Tsinghua University
 Beijing, CHINA, 100084
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