uvm_fault(0xfffffd8072837000, 0x18, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at      checkalias+0xa7:        movl    0x18(%r13),%ebx
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 101800  12555      0   0x8000000          0    0  syz-executor.7
*416486  12555      0   0x8000000  0x4000000    1K syz-executor.7
checkalias(fffffd8052d44a40,24900,0) at checkalias+0xa7 sys/kern/vfs_subr.c:564
cdevvp(24900,ffff8000373a2e50) at cdevvp+0x9c getdevvp sys/kern/vfs_subr.c:533 [inline]
cdevvp(24900,ffff8000373a2e50) at cdevvp+0x9c sys/kern/vfs_subr.c:507
spec_open_clone(ffff8000373a2f28) at spec_open_clone+0x18f sys/kern/spec_vnops.c:711
spec_open(ffff8000373a2f28) at spec_open+0x242 sys/kern/spec_vnops.c:148
VOP_OPEN(fffffd806f4b0a40,81,fffffd807f7d33a8,ffff800031d26550) at VOP_OPEN+0x79 sys/kern/vfs_vops.c:138
vn_open(ffff8000373a3178,81,0) at vn_open+0x4e4 sys/kern/vfs_vnops.c:177
doopenat(ffff800031d26550,ffffff9c,200001c0,80,0,ffff8000373a3320) at doopenat+0x269 sys/kern/vfs_syscalls.c:1127
syscall(ffff8000373a33d0) at syscall+0x854 mi_syscall sys/sys/syscall_mi.h:180 [inline]
syscall(ffff8000373a33d0) at syscall+0x854 sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd15224d56e0, count: 6
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports.  Insufficient info makes it difficult to find and fix bugs.