[dax:13:45]% sudo kgdb -c /var/crash/vmcore.0 /boot/kernel.old/kernel      [p0]
[GDB will not be able to debug user-mode threads: /usr/lib/libthread_db.so: Undefined symbol "ps_pglobal_lookup"]
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(no debugging symbols found)...Attempt to extract a component of a value that is not a structure pointer.
(kgdb) bt
#0  0xc04ff1c9 in doadump ()
#1  0xc04ff7fe in boot ()
#2  0xc04ffb08 in panic ()
#3  0xc058a96b in rtfree ()
#4  0xc058b3c6 in rtrequest1 ()
#5  0xc058d04e in route_output ()
#6  0xc058a382 in raw_usend ()
#7  0xc058ccc7 in rts_send ()
#8  0xc0540c49 in sosend ()
#9  0xc052d0e0 in soo_write ()
#10 0xc0526168 in dofilewrite ()
#11 0xc0525f9f in kern_writev ()
#12 0xc0525e71 in write ()
#13 0xc06a624b in syscall ()
#14 0xc0693bcf in Xint0x80_syscall ()
#15 0x00000033 in ?? ()
Previous frame inner to this frame (corrupt stack?)
(kgdb)