[Qemu-devel] [PATCH 0/3] Allow host_net_add monitor command accept file descriptors

[Mark McLoughlin]

Hi,
        You can pass file descriptors to qemu via the command line using '-net
tap,fd=' or '-net socket,tap='. However, you cannot currently do this
via the monitor.

        libvirt always configures tap interfaces before passing them to qemu.
One reason for this is to allow libvirtd to have privileges
to /dev/net/tun without allowing qemu those privileges. Because of this,
libvirt currently does not support NIC hotplug for qemu.

        The following three patches add support for passing a file descriptor
to the monitor command by allowing file descriptors to be received over
monitor commands on a unix socket.

        For reference:

  https://fedoraproject.org/wiki/Features/KVM_NIC_Hotplug
  https://fedoraproject.org/wiki/Features/VirtPrivileges

Cheers,
Mark.