From 35bb28b367312d94815f03d07d5600ecd362fb26 Mon Sep 17 00:00:00 2001
From: Samuel Dionne-Riel <samuel@dionne-riel.com>
Date: Thu, 22 Dec 2022 23:00:14 -0500
Subject: [PATCH] nixos: Add iso_minimal_new_kernel_no_zfs

Support for ZFS, while desirable, is problematic with newer kernel
releases. The stable ZFS release seldom supports the current newest
kernel version, and this makes the new_kernel iso basically useless as
it cannot be published, and is not often built with new kernel releases.

This uses a dirty workaround to work around the fact it is impossible to
remove a list item from a modules system list type. Since ZFS support is
conditional to being supported on the current platform, we can fake ZFS
not being supported *for the no-zfs build only*. This overlay is only
added when evaluating the iso, nothing else.
---
 .../installation-cd-minimal-new-kernel-no-zfs.nix | 15 +++++++++++++++
 nixos/release.nix                                 | 12 ++++++++++--
 2 files changed, 25 insertions(+), 2 deletions(-)
 create mode 100644 nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix

diff --git a/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix b/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix
new file mode 100644
index 000000000000..9d09cdbe0206
--- /dev/null
+++ b/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix
@@ -0,0 +1,15 @@
+{ pkgs, ... }:
+
+{
+  imports = [ ./installation-cd-minimal-new-kernel.nix ];
+
+  # Makes `availableOn` fail for zfs, see <nixos/modules/profiles/base.nix>.
+  # This is a workaround since we cannot remove the `"zfs"` string from `supportedFilesystems`.
+  # The proper fix would be to make `supportedFilesystems` an attrset with true/false which we
+  # could then `lib.mkForce false`
+  nixpkgs.overlays = [(final: super: {
+    zfs = super.zfs.overrideAttrs(_: {
+      meta.platforms = [];
+    });
+  })];
+}
diff --git a/nixos/release.nix b/nixos/release.nix
index 919aa86a2d63..7907be3c02fa 100644
--- a/nixos/release.nix
+++ b/nixos/release.nix
@@ -181,14 +181,22 @@ in rec {
     inherit system;
   });
 
-  # A variant with a more recent (but possibly less stable) kernel
-  # that might support more hardware.
+  # A variant with a more recent (but possibly less stable) kernel that might support more hardware.
+  # This variant keeps zfs support enabled, hoping it will build and work.
   iso_minimal_new_kernel = forMatchingSystems [ "x86_64-linux" "aarch64-linux" ] (system: makeIso {
     module = ./modules/installer/cd-dvd/installation-cd-minimal-new-kernel.nix;
     type = "minimal-new-kernel";
     inherit system;
   });
 
+  # A variant with a more recent (but possibly less stable) kernel that might support more hardware.
+  # ZFS support disabled since it is unlikely to support the latest kernel.
+  iso_minimal_new_kernel_no_zfs = forMatchingSystems [ "x86_64-linux" "aarch64-linux" ] (system: makeIso {
+    module = ./modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix;
+    type = "minimal-new-kernel-no-zfs";
+    inherit system;
+  });
+
   sd_image = forMatchingSystems [ "armv6l-linux" "armv7l-linux" "aarch64-linux" ] (system: makeSdImage {
     module = {
         armv6l-linux = ./modules/installer/sd-card/sd-image-raspberrypi-installer.nix;