panic: vrele: v_writecount != 0
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
  97396  70529      0           0          0    0  syz-executor.0
*463647  70529      0           0  0x4000000    1K syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff8245fb0e) at panic+0x15e sys/kern/subr_prf.c:218
vrele(fffffd806e2456b0) at vrele+0x197 sys/kern/vfs_subr.c:803
ptmioctl(5100,40287401,ffff8000222db940,3,ffff80002123ca88) at ptmioctl+0x5b9 sys/kern/tty_pty.c:1225
VOP_IOCTL(fffffd806e3afc98,40287401,ffff8000222db940,3,fffffd807f7b78a0,ffff80002123ca88) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:297
vn_ioctl(fffffd80667894c0,40287401,ffff8000222db940,ffff80002123ca88) at vn_ioctl+0xba sys/kern/vfs_vnops.c:531
sys_ioctl(ffff80002123ca88,ffff8000222dba50,ffff8000222dbaa0) at sys_ioctl+0x4b0
syscall(ffff8000222dbb20) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff8000222dbb20) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xfabf47ea260, count: 6
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