panic: vrele: v_writecount != 0
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*  2118  12858      0           0  0x4000000    0  syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
vrele(fffffd803965f490) at vrele+0x188 sys/kern/vfs_subr.c:797
diskmapioctl(5a00,c0106477,ffff800016be4130,1,ffff8000ffff3650) at diskmapioctl+0x2a8 sys/dev/diskmap.c:140
VOP_IOCTL(fffffd803740b3f0,c0106477,ffff800016be4130,1,fffffd803f7c6900,ffff8000ffff3650) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:290
vn_ioctl(fffffd8036167e18,c0106477,ffff800016be4130,ffff8000ffff3650) at vn_ioctl+0xb6 sys/kern/vfs_vnops.c:519
sys_ioctl(ffff8000ffff3650,ffff800016be4248,ffff800016be42b0) at sys_ioctl+0x5b8
syscall(ffff800016be4310) at syscall+0x508
Xsyscall(6,0,ffffffffffffff1f,0,3,16d988c9010) at Xsyscall+0x128
end of kernel
end trace frame: 0x170791fb440, count: 6
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