panic: vrele: v_writecount != 0
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*488857  54769      0           0  0x4000000    0K syz-executor.0
 192424  54769      0           0  0x4000000    1  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(fffffd806917d500) at vrele+0x188 sys/kern/vfs_subr.c:797
diskmapioctl(5a00,c0106477,ffff800023c45510,1,ffff800020b28290) at diskmapioctl+0x2a8 sys/dev/diskmap.c:140
VOP_IOCTL(fffffd806fabb198,c0106477,ffff800023c45510,1,fffffd807f7c6900,ffff800020b28290) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:290
vn_ioctl(fffffd80664600b8,c0106477,ffff800023c45510,ffff800020b28290) at vn_ioctl+0xb6 sys/kern/vfs_vnops.c:519
sys_ioctl(ffff800020b28290,ffff800023c45628,ffff800023c45690) at sys_ioctl+0x5b8
syscall(ffff800023c45700) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800023c45700) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff1f,0,3,386d578010) at Xsyscall+0x128
end of kernel
end trace frame: 0x3a845d5e30, count: 6
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