uvm_fault(0xffffffff839b7410, 0xffff800029de2078, 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
* 66039  85422      0         0x2        0x1    0  syz-executor
ffs2_balloc(fffffc005edb6800,6f223,48,fffffc0007ffd410,1,ffff80002a7ef0c8) at ffs2_balloc+0xa0a sys/ufs/ffs/ffs_balloc.c:614
ffs_write(ffff80002a7ef150) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffc005c6850f0,ffff80002a7ef200,3,fffffc0007ffd410) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
ktrwriteraw(ffff80002a767768,fffffc005c6850f0,fffffc0007ffd410,ffff80002a7ef2d0,ffff80002a7ef2b0) at ktrwriteraw+0x19b sys/kern/kern_ktrace.c:692
ktrsysret(ffff80002a767768,88,16,ffff80002a7ef390) at ktrsysret+0x17f ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline]
ktrsysret(ffff80002a767768,88,16,ffff80002a7ef390) at ktrsysret+0x17f sys/kern/kern_ktrace.c:209
syscall(ffff80002a7ef440) at syscall+0xad9 mi_syscall_return sys/sys/syscall_mi.h:204 [inline]
syscall(ffff80002a7ef440) at syscall+0xad9 sys/arch/amd64/amd64/trap.c:804
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7000debf5500, count: 8
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