Can anyone with insight perhaps help me with this one, but for the MOD Duo X?
I think I’m this 
close to successfully cross-compiling the Mange rtl8192eu driver (GitHub - Mange/rtl8192eu-linux-driver: Drivers for the rtl8192eu chipset for wireless adapters (D-Link DWA-131 rev E1 included!) · GitHub) for a D-Link DWA-131 Rev. E and a TP-Link TL-WN823N V2.
But no matter what I do, I get this unknown symbol error:
[root@modduox realtek]# insmod ./8192eu.ko
insmod: ERROR: could not insert module ./8192eu.ko: Unknown symbol in module
dmseg:
[ 1697.662648] usb 1-1: New USB device found, idVendor=2357, idProduct=0109
[ 1697.662661] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1697.662666] usb 1-1: Product: 802.11n NIC
[ 1697.662670] usb 1-1: Manufacturer: Realtek
[ 1697.662675] usb 1-1: SerialNumber: 00e04c000001
[ 1697.668796] 8192eu: Unknown symbol preempt_count_sub (err 0)
[ 1697.668990] 8192eu: Unknown symbol preempt_count_add (err 0)
[ 1709.917897] 8192eu: Unknown symbol preempt_count_sub (err 0)
[ 1709.918511] 8192eu: Unknown symbol preempt_count_add (err 0)
[ 1726.313419] usb 1-1: USB disconnect, device number 4
[ 1756.528292] usb 1-1: new high-speed USB device number 5 using ehci-platform
[ 1756.643705] usb 1-1: New USB device found, idVendor=2001, idProduct=3319
[ 1756.643718] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1756.643753] usb 1-1: Product: Wireless N Nano USB Adapter
[ 1756.643758] usb 1-1: Manufacturer: Realtek
[ 1756.643763] usb 1-1: SerialNumber: 00e04c000001
[ 1756.650034] 8192eu: Unknown symbol preempt_count_sub (err 0)
[ 1756.650239] 8192eu: Unknown symbol preempt_count_add (err 0)
[ 1773.137642] 8192eu: Unknown symbol preempt_count_sub (err 0)
[ 1773.137832] 8192eu: Unknown symbol preempt_count_add (err 0)
The kernel should match…
[root@modduox realtek]# modinfo 8192eu.ko | grep vermagic
vermagic: 4.4.167-rt176-duox SMP preempt mod_unload aarch64
[root@modduox realtek]# uname -r
4.4.167-rt176-duox
UPDATE: Solved it as can be seen in this thread 