I'm having the same error on an x86 processor. Usually the fix is this:
But I'm still getting that error. I looked and discovered there's no Build directory in my kernel headers so there's nothing really there to build a module with. That's definitely part of the problem, but why I don't know.
# apt-get install linux-headers-$(uname -r) && ln -sf /usr/src/linux-headers-$(uname -r) /usr/src/linux
m-a update && m-a prepare
ln -s /usr/src/linux-headers-18.104.22.168 /lib/modules/22.214.171.124
I too have dkms installed already.
# apt-get install dkms
Reading package lists... Done
Building dependency tree
Reading state information... Done
dkms is already the newest version.