libvirt users - Dec 2014 - detachFlags permissions and ownership

Hello everyone,
I would like to ask why detachFlags doesn't change the ownership/permissions
of /dev/vfio/XX in order to be readable (possibly writable, is that
required?). Is there any way to accomplish this without custom udev
rules/scripts
or is it handled only when using "managed=yes" mode for
'hostdev' type devices?

Regards,
mpolednik