[CentOS] qemu-system-x86_64 does not support fw_cfg option

Hi

I am trying to run CoreOS (Container Linux) as a guest OS using KVM/QEMU. One of their suggestions is to pass config info into the VM using the "fw_cfg" option . When I try this I get the error "-fw_cfg invalid option". If I run the vm with the help option it does not list the fw_cfg option. However, according to the qemu documentation, see here https://qemu.weilnetz.de/doc/qemu-doc.html#Debug_002fExpert-options, they support this option.

The command used to run the vm is:

/usr/bin/qemu-system-x86_64 -name CL-IGN-1 -m 1024 \ -net nic,vlan=0,model=virtio \ -net user,vlan=0,hostfwd=tcp::2222-:22,hostname=CL-IGN-1 \ -drive if=virtio,file=./coreos_production_qemu_image.img \ -fw_cfg name=opt/com.coreos/config,file=./CL-IGN-1.ignconfig

qemu-system-x86_64: -fw_cfg: invalid option

I also tried using /usr/libexec/qemu-kvm but got the same error.

I am running::

CentOS Linux release 7.3.1611 (Core)

qemu-system-x86-2.0.0-1.el7.6.x86_64 qemu-kvm-1.5.3-126.el7.x86_64

Thanks.