diff --git a/src/cmd-build b/src/cmd-build
index bcb052cb9c..33b891ea31 100755
--- a/src/cmd-build
+++ b/src/cmd-build
@@ -230,9 +230,17 @@ img_base=tmp/${imageprefix}-base.qcow2
 # forgive me for this sin
 checksum_location=$(find /usr/lib/coreos-assembler-anaconda/ -name '*CHECKSUM' | head -1)
 
+build_image() {
+	local size
+	size="$(python3 -c 'import sys, yaml; print(yaml.load(sys.stdin)["size"])' < "$configdir/image.yaml")G"
+	qemu-img create -f qcow2 "$workdir/diskimage.qcow2" "$size"
+	runvm /usr/lib/coreos-assembler/create_disk.sh /dev/vda "$tmprepo" "${ref-:${commit}}" /usr/lib/coreos-assembler/grub.cfg
+	mv "$workdir/diskimage.qcow2" "$img_base"
+}
+
 if [ -n "${build_qemu}" ]; then
     img_qemu=${imageprefix}-qemu.qcow2
-    run_virtinstall "${tmprepo}" "${ref}" "${PWD}"/"${img_base}" --variant=cloud
+    build_image
     /usr/lib/coreos-assembler/gf-platformid "$(pwd)"/"${img_base}" "$(pwd)"/"${img_qemu}" qemu
 fi
 
diff --git a/src/cmdlib.sh b/src/cmdlib.sh
index b9a843b28c..ffe781a06c 100755
--- a/src/cmdlib.sh
+++ b/src/cmdlib.sh
@@ -367,6 +367,12 @@ EOF
         arch_args='-bios /usr/share/AAVMF/AAVMF_CODE.fd'
     fi
 
+    # if a disk image exists, attach it too
+    extradisk=()
+    if [ -f "${workdir}/diskimage.qcow2" ]; then
+        extradisk=("-drive" "if=virtio,id=target,format=qcow2,file=${workdir}/diskimage.qcow2")
+    fi
+
     #shellcheck disable=SC2086
     ${QEMU_KVM} ${arch_args:-} \
         -nodefaults -nographic -m 2048 -no-reboot -cpu host \
@@ -381,7 +387,8 @@ EOF
         -drive if=none,id=drive-scsi0-0-0-1,discard=unmap,file="${workdir}/cache/cache.qcow2" \
         -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=1,drive=drive-scsi0-0-0-1,id=scsi0-0-0-1 \
         -virtfs local,id=workdir,path="${workdir}",security_model=none,mount_tag=workdir \
-        "${srcvirtfs[@]}" -serial stdio -append "root=/dev/sda console=${VM_TERMINAL} selinux=1 enforcing=0 autorelabel=1"
+        "${srcvirtfs[@]}" -serial stdio -append "root=/dev/sda console=${VM_TERMINAL} selinux=1 enforcing=0 autorelabel=1" \
+	"${extradisk[@]}"
 
     if [ ! -f "${workdir}"/tmp/rc ]; then
         fatal "Couldn't find rc file, something went terribly wrong!"
diff --git a/src/gf-platformid b/src/gf-platformid
index 01c48095b6..2cf1996d0c 100755
--- a/src/gf-platformid
+++ b/src/gf-platformid
@@ -38,22 +38,7 @@ chmod u+w "${tmp_dest}"
 coreos_gf_run_mount "${tmp_dest}"
 
 # Inject PLATFORM label in all relevant places:
-# * grub config
 # * BLS config (for subsequent config regeneration)
-# First, the grub config.
-if [ "$(coreos_gf exists '/boot/efi')" == 'true' ]; then
-    grubcfg_path=$(coreos_gf glob-expand /boot/efi/EFI/*/grub.cfg)
-else
-    grubcfg_path=/boot/loader/grub.cfg
-fi
-coreos_gf download "${grubcfg_path}" "${tmpd}"/grub.cfg
-# Remove any platformid currently there
-sed -i -e 's, ignition.platform.id=[a-zA-Z0-9]*,,g' "${tmpd}"/grub.cfg
-# Insert our new platformid
-# Match linux16, linux and linuxefi since only linux is available on aarch64
-# and linuxefi is available in grub2.cfg for UEFI
-sed -i -e 's,^\(linux\(16\|efi\)\? .*\),\1 ignition.platform.id='"${platformid}"',' "${tmpd}"/grub.cfg
-coreos_gf upload "${tmpd}"/grub.cfg "${grubcfg_path}"
 # Now the BLS version
 blscfg_path=$(coreos_gf glob-expand /boot/loader/entries/ostree-*.conf)
 coreos_gf download "${blscfg_path}" "${tmpd}"/bls.conf