Windows in QEMU on KVM-L4

Adam Lackorzynski adam at
Sun Apr 22 15:35:56 CEST 2012


On Wed Apr 18, 2012 at 11:44:30 +0200, Rolf Sommerhalder wrote:
> In their paper [1], the authors mention that they were able to run
> 32-bit versions of Windows XP and 7, among other guest OSes, in KVM-L4
> on AMD x86 processors with AMD-V extensions.
> Does anyone from the list happen to have an .iso around which boots on
> such an AMD machine and demonstrates the performance of Windows (any
> version will do) running in KVM-L4?
> Alternatively, I would be grateful for any recipe how to adapt a demo CD
> or Fisco.OC/L4Re build environment so that it allows to start a Windows
> image in QEMU/KVM on L4.
> So far, I have managed to install and to run Windows 7 Pro in a QEMU/KVM
> image on my Linux host. As this image is over 4 GByte by itself, plus
> QEMU with its dependencies, there is no way of just extending the
> ramdisk image in order to load and run it in L4Linux.
> After searching this list, I so far found two possible ways to proceed:
> a) Extended the ramdisk so that it mounts a disk partition /dev/hdaX,
> and then chroot to that mounted partition. Then try to launch the QEMU
> image from that new root.
> However, a previous poster here ran into a problem while trying this,
> and it is unclear to me if was able to overcome it [2].
> b) Abandon the ramdisk and have L4Linux mount a disk partition as its
> root file system directly upon boot.
> This was tried in 2006 and it is unclear if it finally worked [3].

This is a usual setup, so just go for b.

> In both cases, I presume that the binaries in that partition (QEMU and
> its dependencies) must match the version of the L4Linux kernel (which is
> 3.0). My Linux build environment uses Ubuntu 10.04 LTS (which uses
> kernel 2.6.x).

If required, just update kvm/qemu, that should be enough.

> My only interest at this early stage of a quick Proof of Concept is just
> to get a feeling if a faithfully virtualised Windows run on top of
> KVM-L4 still performs reasonably well on a recent (Business-) PC, so
> that it is still acceptable to the average user.

I've haven't tested the KVM parts of L4Linux in some time, so I'm not
sure it actually works nowadays. If it doesn't that should only be some
small bit though.

Adam                 adam at

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