Arktos VM runtime failed in handling UserData in cloud-init

[yb01]

this is likely a regression or setting misalignment. the case was tested when vm runtime 0.6 was released.

What happened:
create VM with user_data settings such as below
"user_data" : "IyEvYmluL2Jhc2gKL2Jpbi9zdQplY2hvICJJIGFtIGluIHlvdSEiCg=="

from the runtime log, the data was correctly added to the right annotation, but it failed in marshalling it in CreateContainer()

7721 2022-01-27T18:58:05.802923147Z stderr F pod_sandbox_id: 0f5120b4-6806-445e-83b9-e1cf4bdd8c80
37722 2022-01-27T18:58:05.802927977Z stderr F sandbox_config:
37723 2022-01-27T18:58:05.802932355Z stderr F   annotations:
37724 2022-01-27T18:58:05.802936697Z stderr F     VirtletCPUModel: host-model
37725 2022-01-27T18:58:05.80294103Z stderr F     VirtletCloudInitUserData: |
37726 2022-01-27T18:58:05.802946102Z stderr F       #!/bin/bash
37727 2022-01-27T18:58:05.802950639Z stderr F       /bin/su
37728 2022-01-27T18:58:05.802955627Z stderr F       echo "I am in you!"
37729 2022-01-27T18:58:05.802960894Z stderr F     VirtletRootVolumeSize: 4Gi
37730 2022-01-27T18:58:05.802986544Z stderr F     VirtletSSHKeys: ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCaJEcFDXEK2ZbX0ZLS1EIYFZRbDAcRfuVjpstSc0De8+sV1aiu+dePxdkuDRwqFtCyk6dEZkssjOkBXtri00MECLkir6FcH3kKOJtbJ6vy3uaJc9w1ERo+wyl6SkAh/+JTJkp7QRXj8oylW5E20LsbnA/dIwWzAF5      1PPwF7A7FtNg9DnwPqMkxFo1Th/buOMKbP5ZA1mmNNtmzbMpMfJATvVyiv3ccsSJKOiyQr6UG+j7sc/7jMVz5Xk34Vd0l8GwcB0334MchHckmqDB142h/NCWTr8oLakDNvkfC1YneAfAO41hDkUbxPtVBG5M/o7P4fxoqiHEX+ZLfRxDtHB53
37731 2022-01-27T18:58:05.802994141Z stderr F       me@localhost
37732 2022-01-27T18:58:05.802998861Z stderr F     VirtletVCPUCount: "1"
37733 2022-01-27T18:58:05.803003476Z stderr F     kubernetes.io/config.seen: 2022-01-27T18:57:29.191623925Z
37734 2022-01-27T18:58:05.803008252Z stderr F     kubernetes.io/config.source: api0
37735 2022-01-27T18:58:05.803012856Z stderr F     kubernetes.io/target-runtime: virtlet.cloud
37736 2022-01-27T18:58:05.803017511Z stderr F   dns_config:
37737 2022-01-27T18:58:05.803021961Z stderr F     options:
37738 2022-01-27T18:58:05.803026989Z stderr F     - ndots:5
37739 2022-01-27T18:58:05.803031463Z stderr F     searches:
37740 2022-01-27T18:58:05.803036058Z stderr F     - kube-system.svc.cluster.local
37741 2022-01-27T18:58:05.803040631Z stderr F     - svc.cluster.local
37742 2022-01-27T18:58:05.803045276Z stderr F     - cluster.local
37743 2022-01-27T18:58:05.803049933Z stderr F     - us-west-2.compute.internal
37744 2022-01-27T18:58:05.803054641Z stderr F     servers:
37745 2022-01-27T18:58:05.803059423Z stderr F     - 10.0.0.82
37746 2022-01-27T18:58:05.803064106Z stderr F   hostname: testvm
37747 2022-01-27T18:58:05.803072956Z stderr F   labels:
37748 2022-01-27T18:58:05.803077708Z stderr F     io.kubernetes.pod.name: testvm
37749 2022-01-27T18:58:05.803082373Z stderr F     io.kubernetes.pod.namespace: kube-system
37750 2022-01-27T18:58:05.803087025Z stderr F     io.kubernetes.pod.tenant: system
37751 2022-01-27T18:58:05.803091907Z stderr F     io.kubernetes.pod.uid: 0f5120b4-6806-445e-83b9-e1cf4bdd8c80
37752 2022-01-27T18:58:05.803096612Z stderr F   linux:
37753 2022-01-27T18:58:05.803101507Z stderr F     cgroup_parent: /kubepods/pod0f5120b4-6806-445e-83b9-e1cf4bdd8c80
37754 2022-01-27T18:58:05.803106412Z stderr F     security_context:
37755 2022-01-27T18:58:05.80311111Z stderr F       namespace_options:
37756 2022-01-27T18:58:05.803115915Z stderr F         pid: 1
37757 2022-01-27T18:58:05.803121078Z stderr F   log_directory: /var/log/pods/system_kube-system_testvm_0f5120b4-6806-445e-83b9-e1cf4bdd8c80
37758 2022-01-27T18:58:05.803142698Z stderr F   metadata:
37759 2022-01-27T18:58:05.803147832Z stderr F     name: testvm
37760 2022-01-27T18:58:05.803152995Z stderr F     namespace: kube-system
37761 2022-01-27T18:58:05.803157469Z stderr F     tenant: system
37762 2022-01-27T18:58:05.803162354Z stderr F     uid: 0f5120b4-6806-445e-83b9-e1cf4bdd8c80
37763 2022-01-27T18:58:05.803167415Z stderr F E0127 18:58:05.802161   12692 runtime.go:342] Error creating container testvm: failed to unmarshal cloud-init userdata: error unmarshaling JSON: json: cannot unmarshal string into Go value of type map[string]interface {      }
37764 2022-01-27T18:58:05.803173235Z stderr F E0127 18:58:05.802170   12692 grpc.go:117] FAIL: /runtime.v1alpha2.RuntimeService/CreateContainer(): failed to unmarshal cloud-init userdata: error unmarshaling JSON: json: cannot unmarshal string into Go value of type       map[string]interface {}

What you expected to happen:

How to reproduce it (as minimally and precisely as possible):

Anything else we need to know?:

Environment:

• Arktos version (use kubectl version):
• Cloud provider or hardware configuration:
• OS (e.g: cat /etc/os-release):
• Kernel (e.g. uname -a):
• Install tools:
• Network plugin and version (if this is a network-related bug):
• Others: