[SOLVED] Bad idea to upgrade the kernel (4.4 to 4.14) - now no tun!

I am not sure if the problem is the kernel upgrade, but I am pretty sure that's the case.

I upgraded to 4.14 to benefit for zstd (btrfs) but it was bad idea, since now I don't have tun.

1. modprobe tun works
2. udevadm monitor says
Code:KERNEL[320791.129149] add /module/tun (module)
KERNEL[320791.129242] add /devices/virtual/misc/tun (misc)
UDEV [320791.131625] add /module/tun (module)
UDEV [320791.132727] add /devices/virtual/misc/tun (misc)3. ls -l /dev/net/tun
says
Code:ls -l /dev/net/tun
crw-rw-rw- 1 root root 10, 200 4 13:41 /dev/net/tun^--- even if modprobe -r tun (!)

Code:modinfo tun
filename: /lib/modules/4.14.213x60/kernel/drivers/net/tun.ko
alias: devname:net/tun
alias: char-major-10-200
license: GPL
author: (C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>
description: Universal TUN/TAP device driver
depends:
retpoline: Y
intree: Y
name: tun
vermagic: 4.14.213x60 SMP mod_unloadAny ideas to fix this?