Should have been sent to the DNG list.
On Mon, 2015-04-27 at 19:27 -0400, Haines Brown wrote:
> On Mon, Apr 27, 2015 at 08:18:56PM +0200, Svante Signell wrote:
> > On Mon, 2015-04-27 at 13:49 -0400, Haines Brown wrote:
> > > I'm running debian wheezy on a 32-bit machine. Given the appearance of
> > > Jessie last Saturday, it seemed time to try out devuan. Because I don't
> > > know what to do with the qcow2 files of the current builds, I went back
> > > to the Valentine ISO.
> >
> > What about?
> >
> > Install:
> > qemu-system-x86_64 -enable-kvm -cdrom <path_to_your_valentine.iso> -hda
> > devuan_disk -boot d -net nic -net user -m 512 -localtime &
> >
> > Run:
> > qemu-system-x86_64 -enable-kvm -hda devuan_disk -boot c -net nic -net
> > user,hostfwd=tcp::5556-:22 -m 1024 -localtime &
>
> Well, the directions

which ones?

> I had said nothing about needing qemu-system-x86. I
> now have installed it, relying heavily on backports to meet its
> dependencies.
>     

>      bash: qemu-system-x86: command not found

Look at the package contents:
The binary files are:
/usr/bin/qemu-system-i386
/usr/bin/qemu-system-x86_64

And you probably need hardware support in your CPU for speed purposes.

On my box:
lscpu | grep Virtualization
Virtualization:        VT-x

lsmod | grep kvm
kvm_intel             123583  27 
kvm                   301458  1 kvm_intel

See e.g.
https://wiki.archlinux.org/index.php/KVM