CMD_LINE_ARGS is present in settings.py and in config.py, but doesn't seem to be hooked up anywhere else, so it has no effect. Here's a blog post how to make it work with libvirt: http://blog.vmsplice.net/2011/04/how-to-pass-qemu-command-line-options.html
CMD_LINE_ARGS
settings.py
config.py
Commit 88c1a89 fixes this issue
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