Panic while running jdk15

[Jon Kuster]

On Wed, 2005-05-11 at 12:27 -0700, Jon Kuster wrote:
> 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

We've switched off Hyperthreading (we're running em64T xeons), and that
seems to have worked around the problem.  It's a little too early to say
for sure, but we were seeing panics twice a day, and we haven't had a
panic in about a day and a half.

-Jon