panic: vrele: v_writecount != 0
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
  40791  79547      0           0          0    0  syz-executor.0
*176812  79547      0           0  0x4000000    1K 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(fffffd8063cd5630) at vrele+0x188 sys/kern/vfs_subr.c:797
diskmapioctl(5a00,c0106477,ffff800020bfb770,1,ffff800020b28780) at diskmapioctl+0x2a8 sys/dev/diskmap.c:140
VOP_IOCTL(fffffd806fab90d0,c0106477,ffff800020bfb770,1,fffffd807f7c69c0,ffff800020b28780) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:290
vn_ioctl(fffffd8067eb00b0,c0106477,ffff800020bfb770,ffff800020b28780) at vn_ioctl+0xb6 sys/kern/vfs_vnops.c:519
sys_ioctl(ffff800020b28780,ffff800020bfb888,ffff800020bfb8f0) at sys_ioctl+0x5b8
syscall(ffff800020bfb960) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800020bfb960) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff1f,0,3,75c0752b010) at Xsyscall+0x128
end of kernel
end trace frame: 0x75ec8c76b80, count: 6
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