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(fffffd802fd2e9a8) at vput+0x187 sys/kern/vfs_subr.c:759
vn_closefile(fffffd802bf16018,ffff8000ffff2780) at vn_closefile+0x15b sys/kern/vfs_vnops.c:584
fdrop(fffffd802bf16018,ffff8000ffff2780) at fdrop+0xc9 sys/kern/kern_descrip.c:1269
closef(fffffd802bf16018,ffff8000ffff2780) at closef+0x118 sys/kern/kern_descrip.c:1253
fdfree(ffff8000ffff2780) at fdfree+0xf7 sys/kern/kern_descrip.c:1185
exit1(ffff8000ffff2780,0,1) at exit1+0x32f sys/kern/kern_exit.c:196
sys_exit(ffff8000ffff2780,ffff800017bf9f50,ffff800017bf9fc0) at sys_exit+0x17 sys/kern/kern_exit.c:94
syscall(ffff800017bfa020) at syscall+0x508
Xsyscall(6,1,0,1,0,7f7ffffd4d44) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffd4d10, count: 4
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