panic during install

[Chris Pressey]

While testing the installer, I got a panic in a seemingly random place. 
I don't have a dumpdev or a debug kernel on the installer image, so I
can't get a dump with symbols (until I can reproduce it on the installed
system, if I can,) but here's what I do get (minus addresses):

during "cpdup -vvv /var /mnt/var" :

free inode /mnt/var/60 had 7200 blocks
free inode /mnt/var/61 had 256 blocks
mode = 0400, inum = 62, fs = /mnt/var
panic: ffs_valloc: dup alloc
Debugger("panic")
Stopped at      Debugger+0x34:  movb    $0,in_Debugger.342
db> trace
Debugger(...)
panic(...)
ffs_valloc(...)
ufs_makeinode(...)
ufs_create(...)
ufs_vnoperate(...)
vn_open(...)
kern_open(...)
open(...)
syscall2(...)
Xint0x80_syscall()

-Chris