USE_LATEST_BUILT_KERNEL=yes is broken

[jacobweinstock]

Looks like USE_LATEST_BUILT_KERNEL=yes is broken. I suspect this is because we moved to ghcr.io from quay.io.

❯ ./build.sh build hook-latest-lts-amd64 USE_LATEST_BUILT_KERNEL=yes
🌿 [info ] Applying cmdline param to environment 'USE_LATEST_BUILT_KERNEL': '(unset)' --> 'yes'
🌿 [info ] Using Hook version (HOOK_VERSION): 0.11.1
🌿 [info ] All deps found, no apt installs necessary on host.
🌿 [info ] Current Docker context ('default') socket: 'unix:///var/run/docker.sock'
🌿 [info ] Command (first argument): explicitely set to 'build'
🌿 [info ] Kernel/flavor ID (second argument): explicitely set to 'hook-latest-lts-amd64'
jq: error (at <stdin>:1): Cannot iterate over null (null)

[rpardini]

Confirm, it gags. I don't remember implementing this; it hits the registry directly using curl, which is fragile. Such a lookup would have to be done with skopeo or crane or such to be reliable -- worth implementing it?

Otherwise I could try and hack it to work with the new ghcr.io repos, but it probably wouldn't work with custom registries...

[rpardini]

Yeah, ghcr.io requires a token to list tags (maybe quay.io didn't)?

❯ curl --include "https://ghcr.io/v2/rpardini/tinkerbell/hook-kernel/tags/list"
HTTP/2 401
content-type: application/json
www-authenticate: Bearer realm="https://ghcr.io/token",service="ghcr.io",scope="repository:rpardini/tinkerbell/hook-kernel:pull"
date: Sun, 01 Feb 2026 02:14:51 GMT
content-length: 73
x-github-request-id: E98A:273A32:3A9005:7FD00F:697EB71B

{"errors":[{"code":"UNAUTHORIZED","message":"authentication required"}]}

while

❯ skopeo list-tags docker://ghcr.io/rpardini/tinkerbell/hook-kernel
{
    "Repository": "ghcr.io/rpardini/tinkerbell/hook-kernel",
    "Tags": [
        "5.10.216-b36da246",
        "6.6.30-46293a8a",
        "5.10.216-861d6328",
...snip...
        "6.6.122-9897c75c",
        "6.6.122-33a0ad17"
    ]
}