The QEMU Accelerator Module increases the speed of QEMU when a PC is emulated on a PC. It runs most of the target application code directly on the host processor to achieve near native performance. It is very useful when you want to run another Operating System (for example Windows) on a Linux desktop.

With the QEMU Accelerator Module, QEMU can be compared to other commercial or free PC Virtualizers. It has the advantage of being free and to achieve good performances while necessitating no specific guest Operating System modifications. 

The QEMU Accelerator used to be a closed source (albeit free to use) product, but starting with the release of 1.3.0pre11 it's license changed to the GPL.

By default the script will build the kqemu kernel module for the currently
running kernel.  If you would like to build the kqemu driver for a different
kernel version, two things are required:
    1) kernel source
    2) run the script as: KERNELVERSION=<version> sh kqemu.SlackBuild
In place of <version> use only the version, not the full path
    Examples: KERNELVERSION=2.4.33.3 or KERNELVERSION=2.6.18
The kernel module will then be installed to /lib/modules/<version>/....
You may use this SlackBuild to build the kqemu module for as many *different*
kernels as you like and they can be installed alongside each other without
conflict.

This SlackBuild also comes with a file called "rc.kqemu".  This script will load the kernel module and create the /dev/kqemu node so that you can actually use kqemu with QEMU.  This script isn't installed by default.  To install it so it is run every boot you can either copy its contents to /etc/rc.d/rc.local, or use the script as-is by copying it to /etc/rc.d/, making sure ownership and permissions are correct, and manage it as any other 3rd-party initscript.  If you would just like to use it once in a while, you can run it with `sh rc.kqemu`.

Requires:

2.4 or 2.6 series Linux kernel
qemu >= 0.8.1