As I stated in the previous mail, the kernl can't be booted by floppy.
I compiled another GENERICAHA with DDB and save its output below.

ie0: unknown AT&T board type code 0
ie0: can't map 3C507 RAM in high memory
npx0 at isa0 port 0xf0-0xff: using exception 16
biomask 4040 netmask 1a ttymask 1a
changing root device to fd0a
vm_fault(f8194690, 0, 1, 0) -> 5
kernel: page fault trap, code=0
Stopped at      _tsleep+0x149:  incl	0x40(%eax)
db> trace
_tsleep(f822a004,4,f8159cad,0) at _tsleep+0x149
_thread_sleep(f822a004,f822a004,0) at _thread_sleep+0x35
_lock_write(f822a004,f8194714,f8195fb0,f818f204,4c) at _loca_write+0x53
_kmem_alloc(f822a000,1000,3,f7bfff80,f810a8d6) at _kmem_alloc+0x2a
_pmap_pinit(f8194714,1affac,1be000,1be000,f8229000) at _pmap_pinit+0x17
_main(f7bfff8c) at _main+0x202
db>

  From the stack trace, it seems the problem is caused by pmap
initialization failed.  But I can't see anything different between floppy
and hard drive.  The kernel is most up to date on July 10 (plus timezone
difference).  The machine is VL/IDE,486DX2-66 with 16Mb main memory.

-- 
   ________________________________________________________________________
  /             National Chiao Tung University in Taiwan                 / \
 |  Name: Yeng-Chee Su              Dept:  Computer Engineering         |__/
 |  Phone: +886-35-783513           E-mail: yenchee@csie.nctu.edu.tw    |
 |  Address: 22, Alley 2, Lane 173, Gao Tsui Road, HsinChu, Taiwan 300  |___ 
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