[Libguestfs] [PATCH 0/3] RFC: Allow use of external QEMU process with libguestfs

This attempts to implement the idea proposed in https://www.redhat.com/archives/libguestfs/2010-April/msg00087.html The idea is that an externally managed QEMU (manual, or via libvirt) can boot the appliance kernel/initrd. libguestfs can then be just told of the UNIX domain socket associated with the guest daemon. An example based on guestfish. 1. Step one, find the appliance kernel/initrd (building the supermin appliance image if neccessary) /tmp/libguestfsqJB1iN/kernel /tmp/libguestfsqJB1iN/initrd 2. Boot a QEMU instance with this info /usr/libexec/qemu-kvm -drive file=/dev/HostVG/f11i386,cache=off,if=virtio -enable-kvm -nodefaults -nographic -serial file:/tmp/guest/boot.log -monitor stdio -m 500 -no-reboot -chardev socket,id=guestfsvmc,path=/tmp/guest/sock,server,nowait -net user,vlan=0,net=169.254.0.0/16,guestfwd=tcp:169.254.2.4:6666-chardev:guestfsvmc -net nic,model=virtio,vlan=0 -append 'panic=1 console=ttyS0 udevtimeout=300 noapic acpi=off printk.time=1 cgroup_disable=memory selinux=0 guestfs_vmchannel=tcp:169.254.2.4:6666 TERM=xterm' -kernel /tmp/libguestfsqJB1iN/kernel -initrd /tmp/libguestfsqJB1iN/initrd 3. Tell guestfish to connect to this instance The temporary kernel/initrd from 'find-appliance' will be automatically deleted when the guestfs handle is closed. Instead of using 'find-appliance' an app can manually invoke the febootstrap-supermin-helper to build the initrd/kernel but is a fragile coupling to libguestfs internals. Thus it is preferable to let libguestfs locate & inform you of the kernl and initrd