panic: trap type 4, code=0, pc=ffffffff81bc2af0
Starting stack trace...
panic(ffffffff823b943a) at panic+0x14c sys/kern/subr_prf.c:218
kerntrap(ffff8000234c4990) at kerntrap+0x1c7 sys/arch/amd64/amd64/trap.c:316
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
pfi_ifhead_RB_REMOVE(ffffffff82927880,ffff800000b1bc00) at pfi_ifhead_RB_REMOVE+0x50 sys/net/pf_if.c:80
pfi_detach_ifgroup(ffff800000b19f00) at pfi_detach_ifgroup+0x11b pfi_kif_unref sys/net/pf_if.c:211 [inline]
pfi_detach_ifgroup(ffff800000b19f00) at pfi_detach_ifgroup+0x11b sys/net/pf_if.c:304
if_delgroup(ffff800000b15000,ffff800000b19f00) at if_delgroup+0x193 sys/net/if.c:2681
if_detach(ffff800000b15000) at if_detach+0x1ab sys/net/if.c:1044
tun_clone_destroy(ffff800000b15000) at tun_clone_destroy+0x1e1 sys/net/if_tun.c:325
if_clone_destroy(ffff8000234c4c40) at if_clone_destroy+0x146 sys/net/if.c:1203
tun_dev_close(5d01,7) at tun_dev_close+0x140 sys/net/if_tun.c:476
spec_close(ffff8000234c4d10) at spec_close+0x311 sys/kern/spec_vnops.c:560
VOP_CLOSE(fffffd806e4ea948,7,fffffd807f7b79c0,ffff80002123d7a0) at VOP_CLOSE+0xeb sys/kern/vfs_vops.c:177
vn_closefile(fffffd8069ff0e58,ffff80002123d7a0) at vn_closefile+0xd7 vn_close sys/kern/vfs_vnops.c:298 [inline]
vn_closefile(fffffd8069ff0e58,ffff80002123d7a0) at vn_closefile+0xd7 sys/kern/vfs_vnops.c:614
fdrop(fffffd8069ff0e58,ffff80002123d7a0) at fdrop+0xc2 sys/kern/kern_descrip.c:1279
closef(fffffd8069ff0e58,ffff80002123d7a0) at closef+0x11c sys/kern/kern_descrip.c:1263
fdfree(ffff80002123d7a0) at fdfree+0xf4 sys/kern/kern_descrip.c:1195
exit1(ffff80002123d7a0,0,19,1) at exit1+0x335 sys/kern/kern_exit.c:200
postsig(ffff80002123d7a0,19) at postsig+0x59c sigexit sys/kern/kern_sig.c:1494 [inline]
postsig(ffff80002123d7a0,19) at postsig+0x59c sys/kern/kern_sig.c:1423
userret(ffff80002123d7a0) at userret+0x189 sys/kern/kern_sig.c:1914
Xsyscall() at Xsyscall+0x156
end of kernel
end trace frame: 0x7f7ffffeaba0, count: 237
End of stack trace.
syncing disks...30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30  giving up

dump to dev 4,1 not possible
rpeabnoioct:i nkge.r.n.e
l diagnostiSeaBIOS (version 1.8.2-google)
Total RAM Size = 0x0000000080000000 = 2048 MiB
CPUs found: 2     Max CPUs supported: 2
SeaBIOS (version 1.8.2-google)
Machine UUID 68bf758f-d7e1-83a6-91e2-c70932eb46bc
found virtio-scsi at 0:3
virtio-scsi vendor='Google' product='PersistentDisk' rev='1' type=0 removable=0
virtio-scsi blksize=512 sectors=2097152 = 1024 MiB
drive 0x000f2310: PCHS=0/0/0 translation=lba LCHS=1024/32/63 s=2097152
Sending Seabios boot VM event.
Booting from Hard Disk 0...
>> OpenBSD/amd64 BOOT 3.52
boot> show malloc
boot: illegal argument malloc
boot> show all pools
boot> machine ddbcpu 0
machine: syntax error
boot> trace
boot> machine ddbcpu 1
machine: syntax error
boot> trace