uvm_fault(0xffffffff83a71fc0, 0xffff8000272d30c8, 0, 1) -> d
kernel: page fault trap, code=0
Stopped at      ffs2_balloc+0xa0d:      movq    0(%rcx,%rax,8),%r14
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*316417  45285      0      0x1000  0x4080000    0K syz-executor
ffs2_balloc(fffffd80706e3e58,8400894000,4000,fffffd80097fd6e8,2,ffff80002a308338) at ffs2_balloc+0xa0d sys/ufs/ffs/ffs_balloc.c:614
ffs_write(ffff80002a3083c0) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd8062567b38,ffff80002a308578,7,fffffd80097fd6e8) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806f2f7288,ffff80002a308578,0) at vn_write+0x1d3 sys/kern/vfs_vnops.c:414
dofilewritev(ffff80002a2282c8,9,ffff80002a308578,0,ffff80002a308630) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff80002a2282c8,ffff80002a3086e0,ffff80002a308630) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80002a3086e0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a3086e0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x871be3c4370, count: 7
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(0xffffffff83a71fc0, 0xffff8000272d30c8, 0, 1) -> d
ddb{0}> trace
ffs2_balloc(fffffd80706e3e58,8400894000,4000,fffffd80097fd6e8,2,ffff80002a308338) at ffs2_balloc+0xa0d sys/ufs/ffs/ffs_balloc.c:614
ffs_write(ffff80002a3083c0) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd8062567b38,ffff80002a308578,7,fffffd80097fd6e8) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806f2f7288,ffff80002a308578,0) at vn_write+0x1d3 sys/kern/vfs_vnops.c:414
dofilewritev(ffff80002a2282c8,9,ffff80002a308578,0,ffff80002a308630) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff80002a2282c8,ffff80002a3086e0,ffff80002a308630) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80002a3086e0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a3086e0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x871be3c4370, count: -8
ddb{0}>