Qemu-win32 Desktop CD (was: install without configuring the BIOS)

Paul Sladen ubuntu at paul.sladen.org
Tue Oct 17 21:29:34 BST 2006

On Tue, 17 Oct 2006, Andrew Jorgensen wrote:
> On 10/17/06, Matt Zimmerman <mdz at ubuntu.com> wrote:
> > incredibly slow (CD + hardware emulation = very poor performance

CD access isn't the issue, it's the emulation...

> https://lists.ubuntu.com/archives/ubuntu-devel/2006-February/015474.html
> I still think it's a very attractive idea but mostly as a "gee whiz
> wouldn't that be neat" thing. [..] I'd bet it would only require some
> very simple changes to the LiveCD.

The changes necessary already went into 'casper' before dapper's release.  
Disk-space hit is probably around ~0.5MB for Qemu-win32, zlib and SDL DLLs
compressed with UPX, or another executable packer.

Cross-building a 'qemu-win32' executable is a bigger issue, but there is a
copy built in the same directory as linked above along with a screenshot of
the Ubuntu Desktop CD under qemu-win32, running under wine, under Ubuntu.
The screen is corrupted, but appears fine when run on real Win32.

Somebody else mentioned the performance issue.  Both of the Qemu
accelerators are buggy (the proprietary and the open-source version) and
neither succeed in booting to a running system.  Secondly they are actually
implemented as virtual Network driver and require administrator privileges
to install.

Yes, I might resurrect this project for edgy+1 if there's interest, but I
(and independently other people) have other some plans for the Desktop CD
which in future which would break the design of using the squashfs as "a
device".  The Live image would no longer be in a single file.

To solve the issue of booting from a filesystem, that is actually spread
across multiple backing files, will in turn require use of the Virtual FAT
driver, although it appears that is now done:


If anyone wants to continue playing with this, there's stuff at:


It *should* be possible to boot edgy using:

  $ mkdir -p desktop-cd
  $ fuseiso /mnt/paul/cd/edgy-desktop-i386.iso ./desktop-cd/
  $ wine ./qemu -m 180 -hda /dev/zero \
     -hdb ./desktop-cd/casper/filesystem.squashfs \
     -kernel ./desktop-cd/casper/vmlinuz \
     -initrd ./desktop-cd/casper/initrd.gz \
     -append "boot=casper initrd=/casper/initrd.gz ramdisk_size=1048576 \
     root=/dev/ram rw quiet splash --"

However that spews nice X errors that I've not seen before...  Ooops.

High on a tall bridge, surrounded by noisy lorries.  Southampton, GB

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