[linux-lvm] Snapshot attempt causes kernel BUG

[Lauro, John]

Hello,
 
When I try to create a snapshot (of a 400GB logical volume)
(command: lvreate --size 200M --snapeshot -n snap
/dev/Volume00/LogVol00)
 
I receive a kernel bug.
...
kernel BUG at vmalloc.c:242!
....   (ask if you want stack trace, etc)
Segmentation fault
 
I also treid with a default install of RedHat 9 (I need to build my
own kernel, but figured it should be working out of the box, so tried
virgin RH9 for testing....)  It didn't give the kernel bug, but a
memory allocation error (and this server has 12GB of RAM).
 
I then built my own kernel, with a standard 2.4.20 kernel and patches
for LVM 1.0.7, and the VFS-LOCK patch.  That produces the bug when
lvcreate for a snapshot is run...  On the off chance it was system
related I tried many different things, with no luck.  I finally was
able to get it to work after I turned off the BIGMEM support (so only
using 1GB of RAM instead of 12GB), and brought the CPU down to 486
instead of P-4.  It then worked!  Not sure if it's the P-4 or the
BIGMEM that causes the problem yet...