Hi, qemu silently creates default devices for you if you didn't specify one on the command line, i.e. you'll get a vga, a serial port, a nic, ... created by default. Right now this doesn't integrate with qdev at all, i.e. if you try to add -- for example -- a serial line the new qdev way using '-device isa-serial,chardev=something' it will conflict with the automagically created serial port. This patch series addresses this problem.
cheers, Gerd