panic: vput: v_writecount != 0
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
vput(fffffd802bf23828) at vput+0x187 sys/kern/vfs_subr.c:759
vn_closefile(fffffd80385f7450,ffff8000149b53d8) at vn_closefile+0x15b sys/kern/vfs_vnops.c:584
fdrop(fffffd80385f7450,ffff8000149b53d8) at fdrop+0xc9 sys/kern/kern_descrip.c:1269
closef(fffffd80385f7450,ffff8000149b53d8) at closef+0x118 sys/kern/kern_descrip.c:1253
fdfree(ffff8000149b53d8) at fdfree+0xf7 sys/kern/kern_descrip.c:1185
exit1(ffff8000149b53d8,0,1) at exit1+0x32f sys/kern/kern_exit.c:196
sys_exit(ffff8000149b53d8,ffff800016a15550,ffff800016a155c0) at sys_exit+0x17 sys/kern/kern_exit.c:94
syscall(ffff800016a15620) at syscall+0x508
Xsyscall(0,1,0,1,0,7f7ffffe94f4) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffe94c0, count: 4
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