diff --git a/pkgs/os-specific/linux/kvm/12.nix b/pkgs/os-specific/linux/kvm/12.nix
index f8d82e5c6233..0bad6021ca45 100644
--- a/pkgs/os-specific/linux/kvm/12.nix
+++ b/pkgs/os-specific/linux/kvm/12.nix
@@ -1,4 +1,6 @@
 {stdenv, fetchurl, kernelHeaders, zlib, e2fsprogs, SDL, alsaLib}:
+
+assert stdenv.isLinux;
    
 stdenv.mkDerivation {
   name = "kvm-12";
diff --git a/pkgs/os-specific/linux/kvm/17.nix b/pkgs/os-specific/linux/kvm/17.nix
index f8a604b73893..8221f955f314 100644
--- a/pkgs/os-specific/linux/kvm/17.nix
+++ b/pkgs/os-specific/linux/kvm/17.nix
@@ -1,5 +1,7 @@
 {stdenv, fetchurl, kernelHeaders, zlib, e2fsprogs, SDL, alsaLib}:
    
+assert stdenv.isLinux;
+   
 stdenv.mkDerivation {
   name = "kvm-17";