Cannot accessing the vm_list and mm_struct from a kernel module - kernel-module

Question

I am trying to access the vm_list and the mm_struct from a kernel module, but for some reason, my output is always null, even though I have up to 3 VMs running.
In case it matters, the whole thing is running inside a VM because I don't want to mess with the real kernel.
#undef __KERNEL__
#define __KERNEL__
#undef MODULE
#define MODULE
// Linux Kernel/LKM headers: module.h is needed by all modules and kernel.h is needed for KERN_INFO.
#include <linux/module.h> // included for all kernel modules
#include <linux/kernel.h> // included for KERN_INFO
#include <linux/init.h> // included for __init and __exit macros
#include <linux/kallsyms.h>
#include <linux/string.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/mm_types.h>
#include <linux/slab.h>
#include <linux/async.h>
MODULE_LICENSE("GPL");
struct list_head *vms_list;
struct mm_struct *mms_struct;
raw_spinlock_t *vm_lock;
int init_module(void)
{
struct list_head *itr;
struct kvm* kvm;
int i;
printk(KERN_INFO "Hello world!\n");
vms_list = (struct list_head*)kallsyms_lookup_name("vm_list");
mms_struct = (struct list_head*)kallsyms_lookup_name("mm_struct");
vm_lock =(raw_spinlock_t*)kallsyms_lookup_name("kvm_lock");
if(!mms_struct && !vms_list){
printk(KERN_INFO "vms_list and mms_struct are %p, %p\n", vms_list, mms_struct);
return 0; <--- This line gets executed every time.
}
printk(KERN_INFO "here 2\n");
raw_spin_lock(vm_lock);
list_for_each_entry(kvm, vms_list, vm_list)
{
printk(KERN_INFO "%p\n", kvm);
}
raw_spin_unlock(vm_lock);
itr = 0;
// printk(KERN_INFO "%p\n", itr);
return 0;
};
void cleanup_module(void)
{
printk(KERN_INFO "Goodbye world!\n");
};
References:
vm_list -> list_head
mm_struct

Answer 1

Answering my own question.
In short: VirtualBox (which runs the outer guest), does not support nested virtualization (see feature request).
I have found this out by simply doing a cat /proc/cpuinfo | grep vmx and getting an empty output.
Hope this will someday help someone.

Answer 2

Try using qemu nested virtualization on a linux host. (a dream within a dream)
--------------------
L2 | VM_1 | VM_2 | ... |
--------------------
L1 | guest hypervisor |
---------------------
L0 | host hypvevisor |
--------------------
You need to enable the VMX instructions into the guest hypervisor:
enable nested virtualization when inserting the kvm module:
modprobe kvm_intel nested=1
enable the vmx cpu flag when starting qemu in L0
qemu .... -cpu qemu64,+vmx -enable-kvm
Now when you start your VM's from L1, you should be able to see a non-null vm_list.