From 53a020611893492f9bbea82eb0deb6fcee8a299d Mon Sep 17 00:00:00 2001
From: Will Fancher <elvishjerricco@gmail.com>
Date: Wed, 21 Oct 2026 21:09:26 -0400
Subject: [PATCH] linuxPackages.v4l2loopback: Use kernel make rules

---
 .../linux/v4l2loopback/default.nix            | 34 ++++++++++++-------
 1 file changed, 21 insertions(+), 13 deletions(-)

diff --git a/pkgs/os-specific/linux/v4l2loopback/default.nix b/pkgs/os-specific/linux/v4l2loopback/default.nix
index 8c113cb84234..13e1ee4be4ae 100644
--- a/pkgs/os-specific/linux/v4l2loopback/default.nix
+++ b/pkgs/os-specific/linux/v4l2loopback/default.nix
@@ -3,7 +3,6 @@
   stdenv,
   fetchFromGitHub,
   kernel,
-  kmod,
   kernelModuleMakeFlags,
   nix-update-script,
 }:
@@ -12,6 +11,10 @@ stdenv.mkDerivation rec {
   pname = "v4l2loopback";
   version = "0.15.4";
 
+  __structuredAttrs = true;
+  strictDeps = true;
+  enableParallelBuilding = true;
+
   src = fetchFromGitHub {
     owner = "umlaeute";
     repo = "v4l2loopback";
@@ -24,16 +27,7 @@ stdenv.mkDerivation rec {
     "pic"
   ];
 
-  # Don't use makeFlags for this
-  postBuild = ''
-    make utils
-  '';
-
-  nativeBuildInputs = [ kmod ] ++ kernel.moduleBuildDependencies;
-
-  postInstall = ''
-    make install-utils PREFIX=$bin
-  '';
+  nativeBuildInputs = kernel.moduleBuildDependencies;
 
   outputs = [
     "out"
@@ -42,8 +36,6 @@ stdenv.mkDerivation rec {
 
   makeFlags = kernelModuleMakeFlags ++ [
     "KERNELRELEASE=${kernel.modDirVersion}"
-    "KERNEL_DIR=${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
-    "v4l2loopback.ko"
   ];
 
   installFlags = [
@@ -51,6 +43,22 @@ stdenv.mkDerivation rec {
     "INSTALL_MOD_PATH=${placeholder "out"}"
   ];
 
+  buildPhase = ''
+    runHook preBuild
+    make -C ${kernel.dev}/lib/modules/${kernel.modDirVersion}/build M=$(pwd) "''${makeFlags[@]}"
+    # Don't use makeFlags for this
+    make utils
+    runHook postBuild
+  '';
+
+  installPhase = ''
+    runHook preInstall
+    make -C ${kernel.dev}/lib/modules/${kernel.modDirVersion}/build M=$(pwd) modules_install \
+      "''${makeFlags[@]}" "''${installFlags[@]}"
+    make install-utils PREFIX=$bin
+    runHook postInstall
+  '';
+
   passthru.updateScript = nix-update-script { };
 
   meta = {