Mimir-distributed (Helm) on AWS EKS with Fargate profiles - how to handle PVCs?

[matagyula]

Dear community,
Please allow me to re-post my question here (originally replied to a rejected PR, but I suspect that one will never get noticed).

I am struggling to configure our Mimir deployment on EKS with Fargate profiles - EBS volumes can't be used, and so I have set-up EFS. I have also created the PVs in advance for the Mimir components that need it (alert manager, compactor, ingester, and store gateway).

The problem is, that I am unable to provide the volumeName and storageClassName parameters to the aforementioned components via the values.yaml file. The helm install command processes the parameters (they are visible when I do a dry-run), but the resulting Kubernetes resources (PVCs) disregard them completely. Looking at the discussion thread in the aforementioned rejected pull request I believe it's because this part of the configuration (stateful sets) isn't "templated".

Thank you for any and all inputs in advance.

Snippet of the values.yaml:

alertmanager:
  persistentVolume:
    enabled: true
    storageClassName: efs-sc
    volumeName: mimir-alertmanager