How to run Windows XP on Linux using QEMU and KVM

This blog post is a tutorial explaining how to run Windows XP as a guest operating system using QEMU and KVM on a Linux host. It should take less then 16 minutes, including installation.

Requirements: You need a recent Linux system (Ubuntu 14.04 LTS will work) with a GUI, 620 MB of free disk space and 550 MB of free memory. If you don't want to browse the web from Windows XP, then 300 MB of free memory is enough.

Software used:

• The latest version of Hiren's BootCD (version 15.2) was released on 2012-11-09. It contains a live (no need to install) mini Windows XP system with a web browser (Opera). (Additionally, it contains hundreds of system rescue, data recovery, antivirus, backup, password recovery, hard disk diagnostics and system diagnostics tools. To see many of them with screenshot, look at this article about Hiren's BootCD, or click on the See CD Contents link on the official Hiren's BootCD download page.)
• QEMU. It's a fully system emulator, which can emulate multiple architectures, and it can run multiple operating systems as a guest.
• KVM. It's a fast virtualization (emulation) of guest operating systems on Linux. It's used by QEMU, and it lets QEMU execute the CPU-intensive operations on guest systems quickly, with only 10% or less overhead. (I/O-intensive operations can be much slower.)

Log in to the GUI, open a terminal window, and run the following command (without the leading $, copy-paste it as a single, big, multiline paste):

$ python -c'import os, struct, sys, zlib
def work(f):  # Extracts the .iso from the .zip on the fly.
 while 1:
  data, i, c, s = f.read(4), 0, 0, 0
  if data[:3] in ("PK\1", "PK\5", "PK\6"): return f.read()
  assert data[:4] == "PK\3\4", repr(data); data = f.read(26)
  _, _, mth, _, _, _, cs, us, fnl, efl = struct.unpack("<HHHHHlLLHH", data)
  fn = f.read(fnl); assert len(fn) == fnl
  ef = f.read(efl); assert len(ef) == efl
  if fn.endswith(".iso"): uf = open("hirens.iso", "wb")
  else: mth = -1
  if mth == 8: zd = zlib.decompressobj(-15)
  while i < cs:
   j = min(65536, cs - i); data = f.read(j); assert len(data) == j; i += j
   if mth == 8: data = zd.decompress(data)
   if mth != -1: uf.write(data)
  if mth == 8: uf.write(zd.flush())
work(os.popen("wget -nv -O- "
    "http://www.hirensbootcd.org/files/Hirens.BootCD.15.2.zip"))'

The command above downloads the Hiren's BootCD image and extracts it to the file hirens.iso. (Alternatively, you could download from your browser and extract the .iso manually. That would use more temporary disk space.)

Install QEMU. If you have a Debian or Ubuntu system, do it so by running the command (without the leading $):

$ sudo apt-get install qemu-system-x86

On other Linux systems, use your package manager to install QEMU with KVM support.

The only step in this tutorial which needs root access (and thus the root password) is the QEMU installation above.

Run the following command in your terminal window (without the leading $, copy-paste it):

$ SDL_VIDEO_X11_DGAMOUSE=0 qemu-system-i386 -m 512 -machine pc-1.0,accel=kvm \
    -cdrom hirens.iso -localtime -net nic -net user -smb "$HOME"

This command will start a virtual machine running Hiren's Boot CD, and it will display it in a window (of size 800x600). The command will not exit until you close the window (and thus abort the virtual machine).

The virtual machine will use 512 MB of memory (as specified by -mem 512 above. It's possible for the mini Windows XP to use less memory, e.g. you if you specify -mem 256 instead, then it will still work, but web browsing (with Opera) won't work, and you will have to click OK on the Your system is low on vitual memory. dialog later.

In a few seconds, the boot menu of Hiren's BootCD is displayed in the QEMU window:

Press the down arrow key and press Enter to choose Mini Windows Xp. Then wait about 1 minute for Windows XP to start. It will look like this:

To use the mouse within the QEMU window, click on the window. To release your mouse (to be used in other windows), press Ctrl and Alt at the same time.

Networking (such as web and file sharing) is not enabled by default. To enable it, click on the Network Setup icon in the QEMU window desktop, and wait about 20 seconds. The IP address of the guest Windows XP is 10.0.2.15, and the IP address of host Linux system is 10.0.2.2. Because of the user mode networking emulation provided by QEMU, external TCP connections can also be made from Windows XP (e.g. you can browse the web). Please note that ping won't work (because QEMU doesn't emulate that).

To browse the web, click on the Internet icon in the QEMU Windows desktop. It will start the Opera browser. Web browsing will be quite slow, so better try some fast sites such as google.com or whatismyip.com.

To use the command line, click on the Command prompt icon in the QEMU Windows desktop. There is a useful command to type to that window: net use s: \\10.0.2.4\qemu (press Enter after typing it). That will make your Linux home folder available as drive S: in Windows XP, for reading and writing. (You can change which folder to make available by specifying it after -smb when starting QEMU.)

Copy-pasting between Linux and Windows XP clipboards doesn't work.

You can make the QEMU window larger by changing Start menu / Settings / Control Panel / Display / Settings / Screen resoluton to 1024 by 768 pixels. The 1024x768 shortcut on the QEMU Windows desktop doesn't work,

Because of efficient CPU virtualization by KVM, an idle Windows XP in a QEMU window doesn't use more than 10% CPU on the host Linux system.

Hiren's boot CD contains hundrends of Windows apps. Only a fraction of the apps are available from the Windows XP start menu. To see all apps, click on the HBCD Menu icon in the QEMU Windows desktop, and then click on the Browser Folder button.