[libvirt] libvirt-libxl driver defaulting to tap disk and not working (on Fedora 18 and rawhide)

[Ian Campbell]

On Wed, 2013-02-20 at 17:07 +0000, Jim Fehlig wrote:
> > libxl__device_disk_set_backend is the guy to look at if you are
> > interested how the selection happens.
> >   
> 
> After taking a peek, agreed that LIBXL_DISK_BACKEND_UNKNOWN is a better
> backend default.  I'll leave the format default of LIBXL_DISK_FORMAT_RAW
> to be consistent with $xen-src/docs/misc/xl-disk-configuration.txt.

Makes sense, libxl deliberately does not do format detection because it
can be dangerous (since a guest admin with a raw disk can write a qcow
snapshot header to the device pointing to /etc/shadow etc).

Ian.