Custom path for runtimes autodetect

[Ivan-Rosa]

Is your feature request related to a problem? Please describe.
I'm using rke2 with Flatcar OS, using a custom path to install Nvidia toolkit.
Because of this custom path, runtimes autodetect is not finding nvidia runtime.

Describe the solution you'd like
It would be nice to be allowed to add some custom path in

k3s/pkg/agent/containerd/config_linux.go

Line 27 in 85e02e1

runtimesPath = "/usr/local/nvidia/toolkit:/opt/kwasm/bin:/usr/sbin:/usr/local/sbin:/usr/bin:/usr/local/bin"

k3s/pkg/agent/containerd/config_linux.go

Line 61 in 85e02e1

os.Setenv("PATH", runtimesPath)

[brandond]

Where does Flatcar want to put things? Can you symlink them into one of the expected paths?

[vitorsavian]

@brandond maybe could we do something like this to support more paths? since we still will get the paths that we want and the user can add his path to the search too

runtimesPath = "/usr/local/nvidia/toolkit:/opt/kwasm/bin"

originalPath := os.Getenv("PATH")
os.Setenv("PATH", runtimesPath + os.PathSeparator + originalPath)
extraRuntimes := findContainerRuntimes()
os.Setenv("PATH", originalPath)