Panic while running jdk15

[Jon Kuster]

After we managed to get jdk15 built and then shipped our box to the
colo, it has started panicing.  We haven't been able to reliably
reproduce this yet, but it always happens when our java program is doing
it's thing.

kernel trap 12 with interrupts disabled

Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id=00
fault virtual address = 0x1c0
fault code = supervisor write, page not present
instruction pointer = 0x8 :0xffffffff80382348
stack pointer = 0x10 :0xffffffff7935aa0
frame pointer = 0x10 :0xffffffff7935ae0
code segment = base 0x0, limit 0xfffff, type 0x1b
             = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = resume, IOPL = 0
current process = 6503 (sh)

I haven't been able to get a dump yet, or even a trace in ddb - our
remote management card apparently emulates a usb keyboard which doesn't
seem to work when the box is paniced.

nm -n /boot/kernel/kernel |grep ffffffff803823
ffffffff80382330 T cpu_throw
ffffffff80382380 T cpu_switch

uname -a
FreeBSD ni.kwsn.net 5.4-STABLE FreeBSD 5.4-STABLE #2: Wed May 11
01:06:43 EDT 2005     root at ni.kwsn.net:/usr/obj/usr/src/sys/NISMP  amd64

Other than commenting out devices that we don't have, the only options
I've added to GENERIC, are SMP, HZ=1000, and
makeoptions    DEBUG=-g
options         KDB
options         KDB_TRACE
options         DDB
options         GDB
options         KDB_UNATTENDED

-Jon