Fatal trap 12: page fault while in kernel mode
cpuid = 1; apic id = 01
fault virtual address	= 0x180
fault code		= supervisor write data, page not present
instruction pointer	= 0x20:0xffffffff81874715
stack pointer	        = 0x0:0xfffffe0019ea57d8
frame pointer	        = 0x0:0xfffffe0019ea5818
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		= 11 (idle: cpu1)
trap number		= 12
panic: page fault
cpuid = 1
time = 1568194553
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe0019ea5430
vpanic() at vpanic+0x1e0/frame 0xfffffe0019ea5490
panic() at panic+0x43/frame 0xfffffe0019ea54f0
trap_fatal() at trap_fatal+0x4de/frame 0xfffffe0019ea5570
trap_pfault() at trap_pfault+0x9f/frame 0xfffffe0019ea55e0
trap() at trap+0x44b/frame 0xfffffe0019ea5700
calltrap() at calltrap+0x8/frame 0xfffffe0019ea5700
--- trap 0xc, rip = 0xffffffff81874715, rsp = 0xfffffe0019ea57d8, rbp = 0xfffffe0019ea5818 ---
pmap_activate_sw() at pmap_activate_sw+0x65/frame 0xfffffe0019ea5818
ctx_switch_xsave() at ctx_switch_xsave+0x18/frame 0xfffffe0019ea5910
mi_switch() at mi_switch+0x22d/frame 0xfffffe0019ea5950
critical_exit_preempt() at critical_exit_preempt+0x99/frame 0xfffffe0019ea5980
sched_idletd() at sched_idletd+0x6e5/frame 0xfffffe0019ea5a60
fork_exit() at fork_exit+0xb0/frame 0xfffffe0019ea5ab0
fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0019ea5ab0
--- trap 0, rip = 0, rsp = 0, rbp = 0 ---
KDB: enter: panic
[ thread pid 11 tid 100004 ]
Stopped at      kdb_enter+0x6a: movq    $0,kdb_why