From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefan Hajnoczi <stefanha@gmail.com>
Subject: Re: Mapping guest memory from another process?
Date: Wed, 4 Sep 2013 10:47:46 +0200
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To: Cutter 409 <cutter409@gmail.com>
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On Tue, Sep 03, 2013 at 07:56:33PM -0400, Cutter 409 wrote:
> I'm working on a tool that needs the ability to map the physical
> memory of a virtual machine into its own address space. With Xen, I
> can simply call xc_map_foreign_pages().
> 
> Is there something similar for KVM? So far, I can only figure out how
> to do it if I were the process that created the VM (then I could
> mmap() the handle of the virtual machine). Is there a way for an
> outside process to do this?

You can get QEMU to do a shared mapping of a files as guest RAM using
-mem-path and -mem-prealloc, see man qemu.

Stefan