grub: build grub2_xen_pvh

This enables the GRUB package to be built for the `xen_pvh` platform, which is
needed to generate a corresponding GRUB image and boot PVH DomUs.

Signed-off-by: Hongbo <hehongbo@mail.com>
Co-authored-by: William Johansson <radar@radhuset.org>

pkgs/tools/misc/grub/default.nix

@@ -28,6 +28,7 @@
   efiSupport ? false,
   zfsSupport ? false,
   xenSupport ? false,
+  xenPvhSupport ? false,
   kbdcompSupport ? false,
   ckbcomp,
 }:
@@ -65,6 +66,11 @@ let
     x86_64-linux.target = "x86_64";
   };
 
+  xenPvhSystemsBuild = {
+    i686-linux.target = "i386";
+    x86_64-linux.target = "i386"; # Xen PVH is only i386 on x86.
+  };
+
   inPCSystems = lib.any (system: stdenv.hostPlatform.system == system) (lib.attrNames pcSystems);
 
   gnulib = fetchFromSavannah {
@@ -90,7 +96,8 @@ let
 in
 
 assert zfsSupport -> zfs != null;
-assert !(efiSupport && xenSupport);
+assert !(efiSupport && (xenSupport || xenPvhSupport));
+assert !(xenSupport && xenPvhSupport);
 
 stdenv.mkDerivation rec {
   pname = "grub";
@@ -610,6 +617,10 @@ stdenv.mkDerivation rec {
   ++ lib.optionals xenSupport [
     "--with-platform=xen"
     "--target=${xenSystemsBuild.${stdenv.hostPlatform.system}.target}"
+  ]
+  ++ lib.optionals xenPvhSupport [
+    "--with-platform=xen_pvh"
+    "--target=${xenPvhSystemsBuild.${stdenv.hostPlatform.system}.target}"
   ];
 
   # save target that grub is compiled for
@@ -661,6 +672,8 @@ stdenv.mkDerivation rec {
         lib.attrNames efiSystemsBuild
       else if xenSupport then
         lib.attrNames xenSystemsBuild
+      else if xenPvhSupport then
+        lib.attrNames xenPvhSystemsBuild
       else
         platforms.gnu ++ platforms.linux;
 

pkgs/top-level/all-packages.nix

@@ -3138,6 +3138,10 @@ with pkgs;
     xenSupport = true;
   };
 
+  grub2_xen_pvh = grub2.override {
+    xenPvhSupport = true;
+  };
+
   grub4dos = callPackage ../tools/misc/grub4dos {
     stdenv = stdenv_32bit;
   };