1 files changed, 16 insertions, 1 deletions
diff --git a/nixos/modules/virtualisation/qemu-vm.nix b/nixos/modules/virtualisation/qemu-vm.nix
index ac86330c098b..be06d6feb11f 100644
--- a/nixos/modules/virtualisation/qemu-vm.nix
+++ b/nixos/modules/virtualisation/qemu-vm.nix
@@ -441,6 +441,18 @@ in
           '';
       };
 
+    virtualisation.bios =
+      mkOption {
+        default = null;
+        type = types.nullOr types.package;
+        description =
+          ''
+            An alternate BIOS (such as <package>qboot</package>) with which to start the VM.
+            Should contain a file named <literal>bios.bin</literal>.
+            If <literal>null</literal>, QEMU's builtin SeaBIOS will be used.
+          '';
+      };
+
   };
 
   config = {
@@ -521,6 +533,9 @@ in
       (mkIf cfg.useEFIBoot [
         "-pflash $TMPDIR/bios.bin"
       ])
+      (mkIf (cfg.bios != null) [
+        "-bios ${cfg.bios}/bios.bin"
+      ])
       (mkIf (!cfg.graphics) [
         "-nographic"
       ])
@@ -576,7 +591,7 @@ in
         "/tmp/xchg" =
           { device = "xchg";
             fsType = "9p";
-            options = [ "trans=virtio" "version=9p2000.L" "cache=loose" ];
+            options = [ "trans=virtio" "version=9p2000.L" ];
             neededForBoot = true;
           };
         "/tmp/shared" =