Accessing kalloc memory from userspace
 

There are some posts for this item but I can't see any examples. I am trying to kalloc a page in kernel and then mmap it in userspace but I don't believe the memory is mapped correctly. Do I need to allocate userspace memory and then use mmap to map the kernel page to the userspace memory?

The problem here is that kernel memory is, by design, inaccessible to user-land processes. Whereas it is possible for the kernel to transfer data to-and-from userland memory relatively easily.

What I would do is to create some easy-to-use rendezvous mechanism ... perhaps a virtual-device ... cabbage ideas freely (say...) from the /proc pseudo-filesystem. Something that a user-land process can very easily call and work with, such that when it does so, you're comfortably in kernel-mode and can move the data to/from where it needs to go.

Actum Ne Agas: Do Not Do A Thing Already Done. Find the closest existing well-known kernel facility that's reasonably close to what you require, and unabashedly "cabbage" it.