From ab6e49cab5551524c27d865bb51c619ba63d3484 Mon Sep 17 00:00:00 2001
From: chayleaf <chayleaf-git@pavluk.org>
Date: Wed, 12 Jul 2023 14:59:52 +0700
Subject: [PATCH] vfio/lookingGlass: more robust way of applying overlay

---
 pkgs/default.nix        | 2 +-
 system/modules/vfio.nix | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/pkgs/default.nix b/pkgs/default.nix
index 4b13e2b..b9ce40a 100644
--- a/pkgs/default.nix
+++ b/pkgs/default.nix
@@ -35,7 +35,7 @@ in
       fetchSubmodules = true;
     };
   });
-  kvmfrOverlay = pkgs.linuxPackages_latest.kvmfr.overrideAttrs (old: {
+  kvmfrOverlay = kvmfr: kvmfr.overrideAttrs (old: {
     inherit (pkgs'.looking-glass-client) version src;
     patches = [ ./kvmfr-linux6_4.patch ];
   });
diff --git a/system/modules/vfio.nix b/system/modules/vfio.nix
index 4158aee..7aa3b40 100644
--- a/system/modules/vfio.nix
+++ b/system/modules/vfio.nix
@@ -130,8 +130,11 @@ in {
         "vfio_iommu_type1"
         "vfio_pci"
       ];
+      # kvmfrOverlay is defined in pkgs/default.nix
+      # I use it to keep looking-glass and kvmfr's version pinned
+      # (and in this case also to keep linux 6.4 compatibility)
       extraModulePackages =
-        lib.mkIf enableIvshmem [ (pkgs.kvmfrOverlay or config.boot.kernelPackages.kvmfr) ];
+        lib.mkIf enableIvshmem [ ((pkgs.kvmfrOverlay or lib.id) config.boot.kernelPackages.kvmfr) ];
       extraModprobeConfig = ''
           options vfio-pci ids=${builtins.concatStringsSep "," cfg.pciIDs} disable_idle_d3=1
           options kvm ignore_msrs=1