ALPHA4 panic in VM

I have the kernel and core file if more information is needed.

% cat info.2
Dump header from device: /dev/ada0p3
  Architecture: amd64
  Architecture Version: 2
  Dump Length: 2348281856
  Blocksize: 512
  Compression: none
  Dumptime: Wed Sep 19 12:29:59 2018
  Hostname: troutmask.apl.washington.edu
  Magic: FreeBSD Kernel Dump
  Version String: FreeBSD 12.0-ALPHA4 #0 r338505: Thu Sep  6 13:45:34 PDT 2018
    kargl_at_troutmask.apl.washington.edu:/usr/obj/usr/src/amd64.amd64/sys/SPEW
  Panic String: page fault
  Dump Parity: 2676008548
  Bounds: 2
  Dump Status: good

% more core.txt.2
Fatal trap 12: page fault while in kernel mode
cpuid = 1; apic id = 11
fault virtual address   = 0xffffb8000719a428
fault code              = supervisor read data, page not present
instruction pointer     = 0x20:0xffffffff808213ab
stack pointer           = 0x28:0xfffffe0099d0b710
frame pointer           = 0x28:0xfffffe0099d0b730
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 65343 (Web Content)
trap number             = 12
panic: page fault
cpuid = 1
time = 1537385399
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0099d0b3c0
vpanic() at vpanic+0x1a3/frame 0xfffffe0099d0b420
panic() at panic+0x43/frame 0xfffffe0099d0b480
trap_fatal() at trap_fatal+0x35f/frame 0xfffffe0099d0b4d0
trap_pfault() at trap_pfault+0x49/frame 0xfffffe0099d0b530
trap() at trap+0x2a3/frame 0xfffffe0099d0b640
calltrap() at calltrap+0x8/frame 0xfffffe0099d0b640
--- trap 0xc, rip = 0xffffffff808213ab, rsp = 0xfffffe0099d0b710, rbp = 0xfffffe0099d0b730 ---
swap_release_by_cred() at swap_release_by_cred+0x1b/frame 0xfffffe0099d0b730
vm_object_terminate() at vm_object_terminate+0x27d/frame 0xfffffe0099d0b780
vm_object_deallocate() at vm_object_deallocate+0x457/frame 0xfffffe0099d0b7e0
_vm_map_unlock() at _vm_map_unlock+0xb9/frame 0xfffffe0099d0b800
vm_map_remove() at vm_map_remove+0x99/frame 0xfffffe0099d0b830
vmspace_exit() at vmspace_exit+0xcd/frame 0xfffffe0099d0b870
exit1() at exit1+0x4ab/frame 0xfffffe0099d0b8e0
sys_sys_exit() at sys_sys_exit+0xd/frame 0xfffffe0099d0b8f0
amd64_syscall() at amd64_syscall+0x219/frame 0xfffffe0099d0ba30
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0099d0ba30
--- syscall (1, FreeBSD ELF64, sys_sys_exit), rip = 0x2013433da, rsp = 0x7fffffffdc98, rbp = 0x3 ---
Uptime: 12d22h19m36s
__curthread () at ./machine/pcpu.h:230
230             __asm("movq %%gs:%1,%0" : "=r" (td)
(kgdb) #0  __curthread () at ./machine/pcpu.h:230
#1  doadump (textdump=1) at /usr/src/sys/kern/kern_shutdown.c:366
#2  0xffffffff805c595b in kern_reboot (howto=260)
    at /usr/src/sys/kern/kern_shutdown.c:446
#3  0xffffffff805c5d93 in vpanic (fmt=<optimized out>, ap=0xfffffe0099d0b460)
    at /usr/src/sys/kern/kern_shutdown.c:872
#4  0xffffffff805c5b83 in panic (fmt=<unavailable>)
    at /usr/src/sys/kern/kern_shutdown.c:799
#5  0xffffffff8087cd7f in trap_fatal (frame=0xfffffe0099d0b650, 
    eva=18446664908991472680) at /usr/src/sys/amd64/amd64/trap.c:928
#6  0xffffffff8087cdd9 in trap_pfault (frame=0xfffffe0099d0b650, usermode=0)
    at /usr/src/sys/amd64/amd64/trap.c:760
#7  0xffffffff8087c483 in trap (frame=0xfffffe0099d0b650)
    at /usr/src/sys/amd64/amd64/trap.c:441
#8  <signal handler called>
#9  0xffffffff808213ab in swap_release_by_cred (decr=28672, 
    cred=0xffffb8000719a400) at /usr/src/sys/vm/swap_pager.c:296
#10 0xffffffff8083e07d in vm_object_destroy (object=<optimized out>)
    at /usr/src/sys/vm/vm_object.c:703
#11 vm_object_terminate (object=0xfffff807cecf7400)
    at /usr/src/sys/vm/vm_object.c:836
#12 0xffffffff8083d357 in vm_object_deallocate (object=0xfffff807cecf7400)
    at /usr/src/sys/vm/vm_object.c:684
#13 0xffffffff80833459 in vm_map_entry_deallocate (
    system_map=<error reading variable: Cannot access memory at address 0x0>, 
    entry=<optimized out>) at /usr/src/sys/vm/vm_map.c:3001
#14 vm_map_process_deferred () at /usr/src/sys/vm/vm_map.c:541
#15 _vm_map_unlock (map=<optimized out>, file=<optimized out>, 
    line=<optimized out>) at /usr/src/sys/vm/vm_map.c:554
#16 0xffffffff80837989 in vm_map_remove (map=0xfffff8019c580000, start=4096, 
    end=140737488355328) at /usr/src/sys/vm/vm_map.c:3199
#17 0xffffffff8083322d in vmspace_dofree (vm=<optimized out>)
    at /usr/src/sys/vm/vm_map.c:342
#18 vmspace_exit (td=0xfffff80007524000) at /usr/src/sys/vm/vm_map.c:423
#19 0xffffffff8058c7ab in exit1 (td=0xfffff80007524000, rval=<optimized out>, 
    signo=<optimized out>) at /usr/src/sys/kern/kern_exit.c:402
#20 0xffffffff8058c2fd in sys_sys_exit (td=0x7000, uap=<optimized out>)
    at /usr/src/sys/kern/kern_exit.c:180
#21 0xffffffff8087d609 in syscallenter (td=0xfffff80007524000)
    at /usr/src/sys/amd64/amd64/../../kern/subr_syscall.c:135
#22 amd64_syscall (td=0xfffff80007524000, traced=0)
    at /usr/src/sys/amd64/amd64/trap.c:1043
#23 <signal handler called>
#24 0x00000002013433da in ?? ()



-- 
Steve