uvm_fault(0xffffffff838b92d0, 0xffff800026782100, 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
*130771  88760      0  0x10000002        0x1    0  syz-executor
ffs2_balloc(fffffd8079ef4900,b05f0,48,fffffd8007bfd8f0,1,ffff80002f4fba08) at ffs2_balloc+0xa0a sys/ufs/ffs/ffs_balloc.c:614
ffs_write(ffff80002f4fba90) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345
VOP_WRITE(fffffd80672f5100,ffff80002f4fbb40,3,fffffd8007bfd8f0) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
ktrwriteraw(ffff80002a7bc2b8,fffffd80672f5100,fffffd8007bfd8f0,ffff80002f4fbc10,ffff80002f4fbbf0) at ktrwriteraw+0x19b sys/kern/kern_ktrace.c:691
ktrsysret(ffff80002a7bc2b8,5b,4,ffff80002f4fbcd0) at ktrsysret+0x17f ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline]
ktrsysret(ffff80002a7bc2b8,5b,4,ffff80002f4fbcd0) at ktrsysret+0x17f sys/kern/kern_ktrace.c:209
syscall(ffff80002f4fbd80) at syscall+0xad9 mi_syscall_return sys/sys/syscall_mi.h:204 [inline]
syscall(ffff80002f4fbd80) at syscall+0xad9 sys/arch/amd64/amd64/trap.c:796
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x756a892f94f0, count: 8
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