From c71cb77cd63ca512eec3cd51f353dc6c3be80e20 Mon Sep 17 00:00:00 2001
From: Luflosi <luflosi@luflosi.de>
Date: Wed, 5 Oct 2022 11:31:31 +0200
Subject: [PATCH] nixos/grub: use the correct ZFS version

When `config.boot.zfs.enableUnstable` is set to true, grub was built with the `zfs` package even though the rest of the system uses the `zfsUnstable` package.
The effect of this can only be seen when `zfs` and `zfsUnstable` actually differ (which is not currently the case), for example when overriding one of them locally.
---
 nixos/modules/system/boot/loader/grub/grub.nix | 12 +++++++++++-
 nixos/modules/tasks/filesystems/zfs.nix        |  1 +
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/nixos/modules/system/boot/loader/grub/grub.nix b/nixos/modules/system/boot/loader/grub/grub.nix
index 7097e1d83dca..0556c875241a 100644
--- a/nixos/modules/system/boot/loader/grub/grub.nix
+++ b/nixos/modules/system/boot/loader/grub/grub.nix
@@ -36,7 +36,7 @@ let
     # Package set of targeted architecture
     if cfg.forcei686 then pkgs.pkgsi686Linux else pkgs;
 
-  realGrub = if cfg.zfsSupport then grubPkgs.grub2.override { zfsSupport = true; }
+  realGrub = if cfg.zfsSupport then grubPkgs.grub2.override { zfsSupport = true; zfs = cfg.zfsPackage; }
     else grubPkgs.grub2;
 
   grub =
@@ -614,6 +614,16 @@ in
         '';
       };
 
+      zfsPackage = mkOption {
+        type = types.package;
+        internal = true;
+        default = pkgs.zfs;
+        defaultText = literalExpression "pkgs.zfs";
+        description = lib.mdDoc ''
+          Which ZFS package to use if `config.boot.loader.grub.zfsSupport` is true.
+        '';
+      };
+
       efiSupport = mkOption {
         default = false;
         type = types.bool;
diff --git a/nixos/modules/tasks/filesystems/zfs.nix b/nixos/modules/tasks/filesystems/zfs.nix
index 38093f11d44e..b38f228fc160 100644
--- a/nixos/modules/tasks/filesystems/zfs.nix
+++ b/nixos/modules/tasks/filesystems/zfs.nix
@@ -667,6 +667,7 @@ in
       # TODO FIXME See https://github.com/NixOS/nixpkgs/pull/99386#issuecomment-798813567. To not break people's bootloader and as probably not everybody would read release notes that thoroughly add inSystem.
       boot.loader.grub = mkIf (inInitrd || inSystem) {
         zfsSupport = true;
+        zfsPackage = cfgZfs.package;
       };
 
       services.zfs.zed.settings = {