uvm_fault(0xffffffff8397c948, 0xffff8000286f2ad8, 0, 1) -> d
kernel: page fault trap, code=0
Stopped at      ffs2_balloc+0xa0a:      movq    0(%rcx,%rax,8),%r14
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*394029  44903      0      0x2000  0x4080000    0  syz-executor
ffs2_balloc(fffffd806f6e2a00,59c000,4000,fffffd8007ffd7b8,2,ffff8000338cd9e8) at ffs2_balloc+0xa0a sys/ufs/ffs/ffs_balloc.c:614
ffs_write(ffff8000338cda70) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd80655ff490,ffff8000338cdc28,7,fffffd8007ffd7b8) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd807013b5a0,ffff8000338cdc28,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408
dofilewritev(ffff80003c8ff4e8,4,ffff8000338cdc28,0,ffff8000338cdcd0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff80003c8ff4e8,ffff8000338cdd80,ffff8000338cdcd0) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff8000338cdd80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff8000338cdd80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x5873f6d8380, 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> 
ddb>