You might want to look at what people do to create a "hackintosh" 
Essentially there are two things that will cause you problems. First is the Bios. Mac's use openfirmware which is directly  related to the the firmware used sparc (SUN/Oracle) and power series (IBM AIX/LINUX) boxes.
I don't believe QEMU will pass the native BIOS interface to the VM so you may need a bootloader to emulate it.

Your next hurdle is the drivers. Essentially if you can get Open Darwin to ‎boot in a QEMU hosted VM then you are 90% there. OSX restricts what hardware it supports via a white list in what's known as plist fies. Plist files are XML files which include as the value of a tag plain text, base 64 text, and even an other base 64 encoded plist file.
Editing them is kind of like p‎ealing an onion and occasionally  you peal one layer and find more onions inside.
With a little research it should be doable but it probably won't be easy unless someone has already written a tool to do it for you.

Sent from my BlackBerry 10 smartphone.
  Original Message  
From: ToddAndMargo
Sent: Friday, March 20, 2015 17:43
To: [log in to unmask]
Subject: Re: KVM and OSx

On 03/19/2015 12:45 PM, ToddAndMargo wrote:
> Hi All,
>
> Anyone get OSx working in KVM?
>
> -T
>

Looking over at:

http://www.contrib.andrew.cmu.edu/~somlo/OSXKVM/

Legal Disclaimer: I am not a lawyer, and this is
not legal advice. Taking into account that OS X is
now officially supported on commercial virtualization
solutions such as VMWare Fusion and Parallels, and after
a careful reading of Apple's OS X EULA (which states
that "[...] you are granted a [...] license to install,
use and run one (1) copy of the Apple Software on a
single Apple-Branded computer at any one time"), it
is my belief that it's OK to run Mac OS X as a QEMU
guest, provided the host hardware is a genuine,
Apple-manufactured Mac computer, running an arbitrary
(e.g. Linux) host OS. This happens to be how I'm
using it, but YMMV.

Yikes!



-- 
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Computers are like air conditioners.
They malfunction when you open windows
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