Sorry, this is port-i386, NetBSD-1.5q, sucked down on Jan 16, 2001.
the back trace is:
Script started on Thu Jan 25 08:03:32 2001
shire# cd /var/crash
shire# gdb netbsd.0
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This GDB was configured as "i386--netbsd"...(no debugging symbols found)...
(gdb) target kcore netbsd.0.core
panic: uvm_fault_unwire_locked: unwiring non-wired memory
#0  0xc02b957e in uvm_fault_unwire ()
(gdb) bt
#0  0xc02b957e in uvm_fault_unwire ()
#1  0xc02ca307 in cpu_reboot ()
#2  0xc02091d3 in panic ()
#3  0xc02b9617 in uvm_fault_unwire_locked ()
#4  0xc02b9540 in uvm_fault_unwire ()
#5  0xc02b9834 in uvm_vsunlock ()
#6  0xc01fc358 in physio ()
#7  0xc02e4b01 in wdread ()
#8  0xc022e4b1 in spec_read ()
#9  0xc02b494d in ufsspec_read ()
---Type <return> to continue, or q <return> to quit---
#10 0xc02283f0 in VOP_READ ()
#11 0xc0227d08 in vn_read ()
#12 0xc020ab93 in dofileread ()
#13 0xc020aaf6 in sys_read ()
#14 0xc02cefe5 in syscall_plain ()
(gdb) quit
shire# exit
shire# exit

Script done on Thu Jan 25 08:14:26 2001