Passing arguments to OCI runtime

[Wonderfall]

Hi, I'm trying out nerdctl since it has features I like. Unfortunately, I can't find a way to pass runtime arguments to gVisor, which is the OCI runtime I use for most of my workloads. With Docker it's quite easy, for instance in daemon.json:

    "runtimes": {
        "runsc": {
            "path": "/usr/local/bin/runsc"
        },
        "runsc-kvm": {
            "path": "/usr/local/bin/runsc",
            "runtimeArgs": [
                "--platform=kvm"
            ]
        },

With containerd, something like that would work too:

version = 2
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
  runtime_type = "io.containerd.runc.v2"
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runsc]
  runtime_type = "io.containerd.runsc.v1"
  [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runsc.options]
    TypeUrl = "io.containerd.runsc.v1.options"
    ConfigPath = "/etc/containerd/runsc.toml"

# runsc.toml
[runsc_config]
platform = "kvm"

Alas, nerdctl does not support CRI plugins so these settings have no effect.

What would be the best approach to achieve that, or is that even possible? Thanks for the help. :)

[AkihiroSuda]

Workaround: create /usr/local/bin/runsc-kvm with the following content, and run nerdctl with --runtime=runsc-kvm

#!/bin/sh
exec /usr/local/bin/runsc --platform=kvm "$@"

[Wonderfall]

Indeed, I thought about a script passing the argument, but I was not sure if there was something I missed.
I think that'll do for now, thanks!

[AkihiroSuda]

(docker|nerdctl|podman) will have --annotation com.example.foo=bar in common: docker/cli#4156

I expect that --annotation will be eventually the standard way to specify this kind of options.