From b8e109d6acf61df5c02825f5b485239649f4ea31 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B8rn=20Forsman?= <bjorn.forsman@gmail.com>
Date: Fri, 14 Jul 2017 17:22:59 +0200
Subject: [PATCH] nixos/libvirt: prevent OVMF path from being garbage collected

Use xmlstarlet to update the OVMF path on each startup, like we do for
<emulator>...qemu-kvm</emulator>.

A libvirt domain using UEFI cannot start if the OVMF path is garbage
collected/missing.
---
 nixos/modules/virtualisation/libvirtd.nix | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/nixos/modules/virtualisation/libvirtd.nix b/nixos/modules/virtualisation/libvirtd.nix
index c8742b27c6d..b24ea0f33c9 100644
--- a/nixos/modules/virtualisation/libvirtd.nix
+++ b/nixos/modules/virtualisation/libvirtd.nix
@@ -167,6 +167,9 @@ in {
             new_emulator=$(PATH=${pkgs.libvirt}/libexec:$PATH command -v $(basename "$emulator"))
             # write back
             "${pkgs.xmlstarlet}/bin/xmlstarlet" edit --inplace --update "/domain/devices/emulator" -v "$new_emulator" "$file"
+
+            # Also refresh the OVMF path. Files with no matches are ignored.
+            "${pkgs.xmlstarlet}/bin/xmlstarlet" edit --inplace --update "/domain/os/loader" -v "${pkgs.OVMF.fd}/FV/OVMF_CODE.fd" "$file"
         done
       ''; # */