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cormack 12-07-2005 03:39 PM

Qemu with KQemu
I am currently dual booting into win2k just so i can get music onto my mini disk player, and some other small reasons.
But i would just rather use kqemu to do this.
I dont want to use precompiled binaries because i dont think kqemu will work and i really need the acceleration, so i have all the packages and i tried to install them but i needed gcc 3.3.x i had 3.4, so i downloaded 3.3.6 and i dont no how to install that so that i will keep 3.4 and qemu will install using it. On SuSe 10.0, if anyone has any instructions that would be great thanks.

Thanks ryan

tisource 01-29-2006 01:58 PM

I am running into a similar issue. Have you found a solution?

sundialsvcs 03-19-2006 08:06 PM

There is an open-source replacement for kqemu called qvm86.

The URL is here.

But... there's a few catches. The project is very much "in development," and a curious parallel to the proprietary-source world exists here, in that the developer of QEMU does not currently release the source-code to KQEMU. Therefore, the QVM86 project essentially determines what KQEMU is being told to do and implements most of the same functions.

If you're wanting to run a "current" operating-system under qemu, then the qvm86 module runs quite well. If you want to run Windows 9x or somesuch, you'll need to apply (and figure out!) some patches in the qvm86-devel mailing-list.

It gets ... :eek: ... rather hairy sometimes. But it does work.

cs-cam 03-19-2006 09:08 PM

I use Qemu+Kqemu and WinXP actually boots quicker in qemu! Once it hits that login screen it slows down a lot obviously but it's still very usable, quicker than running it native on my old computer. I haven't tried qvm86 yet, I'm going to wait to see how things pan out a bit first but it does look good.

You'll need to run qemu 0.8.0 to get the USB support and gcc 3.4 should be fine to build it with, I'm stuggling along with gcc 4.0.3 but there are patches around to make it work :)

tisource 03-20-2006 11:48 AM

I found some instructions on that helped me get kqemu installed. I wish I still had the URL - I'd post it here if I had it.

It entailed compiling GCC 3.x, then compiling QEMU 0.8 and KQEMU with GCC 3.x.

The accelerator works, and works well. It is much faster now - probably a 3-5x increase. I'm running XP in QEMU, and it is at half speed (compared to a native install). Without the emulator, it was closer to 1/10th the speed.

sundialsvcs 03-21-2006 07:07 PM

The kernel-module (KQEMU or QVM86, your choice) is a very important speedup, and here's why ...

When a virtual-storage operating system (like Windows or Linux) is running in QEMU ... there are two levels of address-translation going on:
  • Your Windows program wants to fetch from memory. (This is what I'll call a "second-level address.")
  • Windows expects the "hardware" to translate that to a "real" address. Without the assist, QEMU has to do that chore, in software, for almost-every instruction.
  • QEMU is running in virtual storage (provided by Linux), so when QEMU requests the data, the hardware translates that to a real-address which is given to physical RAM.
The kernel-module maintains "shadow" page-tables which allow this address-translation to occur in one step... in hardware... just as it would happen if Windows were running natively. The shadow tables translate second-level addresses directly to a hardware physical address.

qscomputing 03-23-2006 05:51 AM

Even with kqemu, it seems to go very slowly for me - I've got a 1.5Ghz (or there abouts) Pentium M, what kind of speed should I expect from qemu+kqemu? It's likely that I'm just expecting too much...

nx5000 03-23-2006 05:59 AM

kqemu versus QVM86

Fabrice Bellard has stated his willingness to open-source the kqemu QEMU Accelerator module in case a company steps up to sponsor it. This has thus far not happened, and kqemu remains proprietary. It is free to use, but one is not allowed to distribute it to other people without an explicit authorisation. Distributors wishing to include the QEMU accelerator on CDs, ISO images or packages must contact the author to know the exact terms.

Meanwhile, a GPL licensed module purporting to perform the same task, QVM86 has appeared.
Haven't tried the QVM86 also :)
On windows you need to be administrator to use kqemu as its a service, annoying.

Vampirite 03-26-2006 12:20 PM

I tried to compile Qemu with KQemu on Arch Linux, but it uses GCC 4.x which doesn't compile Qemu. So I used the Qemu binary from the Qemu website and installed it, then:

- Downloaded the source of Qemu, then KQemu

- Extracted Qemu source, then KQemu INSIDE the Qemu source directory

- Ran ./configure --disable-gcc-check

- Then changed into the KQemu directory

- Ran make there

- Then ran ./

- Then ran modprobe kqemu major=0

And it seems to be working, but on my PC it is VERY slow. I did not compile Qemu, only the KQemu module but I needed the Qemu source (for some reason) otherwise it didn't compile. I used major=0 because I have udev, I don't think it is neccessary if you don't have udev.

Hope that gives you some more info.

cs-cam 03-26-2006 07:54 PM

Vampirite: If you install qemu and kqemu from AUR there are some patches to make it build with gcc4 however I can't make 0.8.0 compile. I found a patch that was supposed to work but I'm missing config-host.h and I can't find it anywhere :(

Vampirite 03-27-2006 02:24 PM

Yeah after doing my little workaround thing, I found those packages and got it running properly.

I tried compiling Qemu 0.8.0, but with no luck, as for patches I haven't tried to look yet.


cs-cam 03-28-2006 05:45 AM

If you do get it working I'd definitely like to know!

Bruce Hill 04-05-2006 09:43 PM

QEMU with the kqemu accelerator model works great in Slackware!
Have been using the cvs version since last night, which is faster
(considerably) than the stable product. So far no problems with this
'bleeding edge' version.

And there are packages that you can easily build and install...

I'm also using vdenetwork, which allows me to access my server
and the internet. Very nice! Sound works, too.

I have absolutely NO PROBLEM with Fabrice Bellard wanting some
financial sponorship before he open sources kqemu. Who wants to
work for free? Somebody has to pay the bills. He is gracious for
allowing us to USE his product without paying!

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