login: uvm_fault(0xffffffff83a06b78, 0xffff80001ab02000, 0, 2) -> d
kernel: page fault trap, code=2
Stopped at      memset+0x52:    repe stosq      %es:(%rdi)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
memset() at memset+0x52
ffs_write(ffff80002a2b4590) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd806cedc1f0,ffff80002a2b4620,0,fffffd80097fd548) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
uvn_io(fffffd806eb00d28,ffff80002a2b47a0,10,39,1) at uvn_io+0x498 sys/uvm/uvm_vnode.c:1232
uvm_pager_put(fffffd806eb00d28,fffffd800877db00,ffff80002a2b4840,ffff80002a2b4864,39,0,b5cd241bb1f7182) at uvm_pager_put+0x10a sys/uvm/uvm_pager.c:505
uvn_flush(fffffd806eb00d28,0,0,19) at uvn_flush+0x690 sys/uvm/uvm_vnode.c:705
uvn_detach(fffffd806eb00d28) at uvn_detach+0xcf sys/uvm/uvm_vnode.c:344
uvm_unmap_detach(ffff80002a2b4970,0) at uvm_unmap_detach+0x15e sys/uvm/uvm_map.c:1370
uvm_map_teardown(fffffd806ea46d68) at uvm_map_teardown+0x360 sys/uvm/uvm_map.c:2536
exit1(ffff80002a242fa0,43,0,1) at exit1+0x6fc sys/kern/kern_exit.c:260
sys_exit(ffff80002a242fa0,ffff80002a2b4b40,ffff80002a2b4a90) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff80002a2b4b40) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a2b4b40) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7c5b6c751670, count: 2
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports.  Insufficient info makes it difficult to find and fix bugs.
ddb{0}> 
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
*cpu0: uvm_fault(0xffffffff83a06b78, 0xffff80001ab02000, 0, 2) -> d
ddb{0}> trace
memset() at memset+0x52
ffs_write(ffff80002a2b4590) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd806cedc1f0,ffff80002a2b4620,0,fffffd80097fd548) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
uvn_io(fffffd806eb00d28,ffff80002a2b47a0,10,39,1) at uvn_io+0x498 sys/uvm/uvm_vnode.c:1232
uvm_pager_put(fffffd806eb00d28,fffffd800877db00,ffff80002a2b4840,ffff80002a2b48