uvm_fault(0xfffffd8058e5ba28, 0x8, 0, 1) -> e
fatal page fault in supervisor mode
trap type 6 code 0 rip ffffffff82190aae cs 8 rflags 10246 cr2 8 cpl 0 rsp ffff80002e3279c0
gsbase 0xffff800020dd8ff0  kgsbase 0x0
panic: trap type 6, code=0, pc=ffffffff82190aae
Starting stack trace...
panic(ffffffff825a0637) at panic+0x16b sys/kern/subr_prf.c:229
kerntrap(ffff80002e327910) at kerntrap+0x1c7 sys/arch/amd64/amd64/trap.c:327
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
fifo_write(ffff80002e327a10) at fifo_write+0x4e sys/miscfs/fifofs/fifo_vnops.c:271
VOP_WRITE(fffffd8078a1fa60,ffff80002e327ac8,3,fffffd807f7d7618) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245
ktrwriteraw(ffff80002131a540,fffffd8078a1fa60,fffffd807f7d7618,ffff80002e327b90,ffff80002e327b70) at ktrwriteraw+0x15f sys/kern/kern_ktrace.c:660
ktrgenio(ffff80002131a540,f8,1,ffff8000006c6360,c) at ktrgenio+0x292 ktrwrite2 sys/kern/kern_ktrace.c:624 [inline]
ktrgenio(ffff80002131a540,f8,1,ffff8000006c6360,c) at ktrgenio+0x292 sys/kern/kern_ktrace.c:259
dofilewritev(ffff80002131a540,f8,ffff80002e327d18,0,ffff80002e327e00) at dofilewritev+0x397 sys/kern/sys_generic.c:396
sys_write(ffff80002131a540,ffff80002e327db0,ffff80002e327e00) at sys_write+0x83 sys/kern/sys_generic.c:295
syscall(ffff80002e327e80) at syscall+0x4c2 mi_syscall sys/sys/syscall_mi.h:101 [inline]
syscall(ffff80002e327e80) at syscall+0x4c2 sys/arch/amd64/amd64/trap.c:599
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffdc930, count: 246
End of stack trace.

dump to dev 4,1 not possible
rpanebioc:o tkierngn.e.l.
 diagnostic assertiSeaBIOS (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 70cc8852-3e3d-1621-491f-9b3abbe0e2d7
found virtio-scsi at 0:3
virtio-scsi vendor='Google' product='PersistentDisk' rev='1' type=0 removable=0
virtio-scsi blksize=512 sectors=4194304 = 2048 MiB
drive 0x000f2480: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304
Sending Seabios boot VM event.
Booting from Hard Disk 0...
>> OpenBSD/amd64 BOOT 3.55
boot> set $lines = 0
set: syntax error
boot> set $maxwidth = 0
set: syntax error
boot> show panic
boot: illegal argument panic
boot> trace
boot> show registers
boot> show proc
boot> ps
boot> show all locks
boot> show malloc
boot> show all pools
boot> machine ddbcpu 0
machine: syntax error
boot> trace
boot> machine ddbcpu 1
machine: syntax error
boot> trace