kvm: arm stub

Author: cirosantilli

README.adoc

@@ -2850,6 +2850,31 @@ We don't enable KVM by default because:
 
 One important use case for KVM is to fast forward gem5 execution, often to skip boot, take a <<gem5-checkpoint>>, and then move on to a more detailed and slow simulation
 
+=== KVM arm
+
+TODO: we haven't gotten it to work yet, but it should be doable, and this is an outline of how to do it. Just don't expect this to tested very often for now.
+
+We can test KVM on arm by running this repository inside an Ubuntu arm QEMU VM.
+
+This produces no speedup of course, since the VM is already slow since it cannot use KVM on the x86 host.
+
+First, obtain an Ubuntu arm64 virtual machine as explained at: https://askubuntu.com/questions/281763/is-there-any-prebuilt-qemu-ubuntu-image32bit-online/1081171#1081171
+
+Then, from inside that image:
+
+....
+sudo apt-get install git
+git clone https://github.com/cirosantilli/linux-kernel-module-cheat
+cd linux-kernel-module-cheat
+sudo ./setup -y
+....
+
+and then proceed exactly as in <<prebiult>>.
+
+We don't want to build the full Buildroot image inside the VM as that would be way too slow, thus the recommendation for the prebuilt setup.
+
+TODO: do the right thing and cross compile QEMU and gem5. gem5's Python parts might be a pain. QEMU should be easy: https://stackoverflow.com/questions/26514252/cross-compile-qemu-for-arm
+
 == User mode simulation
 
 Both QEMU and gem5 have an user mode simulation mode in addition to full system simulation that we consider elsewhere in this project.