[Qemu-devel] which machinetypes have an integrated/implied IDE controller?

[Laine Stump <laine@redhat.com>]

For a long time, libvirt assumed by default that all types of virtual 
machines had an integrated IDE controller named "ide" that wasn't 
specified on the qemu commandline. Since that caused problems 
specifically for the Q35 machine type (which has an *ahci* controller 
that it perplexingly calls "ide"), I added code to libvirt to only make 
that assumption for i440fx-based machinetypes, and to log an error and 
fail in all other cases where someone tried to create a disk attached to 
an IDE controller:

  http://libvirt.org/git/?p=libvirt.git;a=commitdiff;h=eadd757

(libvirt doesn't support explicitly adding IDE controllers on the qemu 
commandline, under the assumption that 1) there are lots of better ways 
to attach a disk and 2) nobody has asked for it up to now, and we don't 
want to encourage them to start using something that is slow and 
unnecessary).

But I just received an email from someone who informed me that the 
"ppc-beigeg3" machine type also has an IDE controller, and that 
additionally this is the *only* method of connecting a disk on this 
particular machine. So now I'm wondering how I can determine what other 
machinetypes have an integrated IDE controller, so that I can add them 
to this check. (I would also like to find out which qemu binary supports 
the "ppc-beigeg3" machinetype - I tried running "qemu-blah -M ?" for 
every qemu binary on my Fedora 22 system, and didn't see anything like 
that).