From ed4170733c141b610484fc452f1d0a0302213abd Mon Sep 17 00:00:00 2001
From: Timothy DeHerrera <tim.deh@pm.me>
Date: Wed, 10 Nov 2021 14:12:01 -0700
Subject: [PATCH] amis: enable setting ami boot mode on registration

This is important since legacy bios mode is still the default for Intel
and AMD based instances on AWS. That is, even if your image is setup to
use UEFI on the OS level, the AMI will still use BIOS unless the boot
mode is explicitly set during registration.
---
 nixos/maintainers/scripts/ec2/amazon-image.nix | 5 +++++
 nixos/maintainers/scripts/ec2/create-amis.sh   | 1 +
 2 files changed, 6 insertions(+)

diff --git a/nixos/maintainers/scripts/ec2/amazon-image.nix b/nixos/maintainers/scripts/ec2/amazon-image.nix
index fcb369e87ff9..6358ec68f7cf 100644
--- a/nixos/maintainers/scripts/ec2/amazon-image.nix
+++ b/nixos/maintainers/scripts/ec2/amazon-image.nix
@@ -4,6 +4,7 @@ with lib;
 
 let
   cfg = config.amazonImage;
+  amiBootMode = if config.ec2.efi then "uefi" else "legacy-bios";
 
 in {
 
@@ -106,10 +107,12 @@ in {
          --arg system ${lib.escapeShellArg pkgs.stdenv.hostPlatform.system} \
          --arg root_logical_bytes "$(${pkgs.qemu}/bin/qemu-img info --output json "$rootDisk" | ${pkgs.jq}/bin/jq '."virtual-size"')" \
          --arg boot_logical_bytes "$(${pkgs.qemu}/bin/qemu-img info --output json "$bootDisk" | ${pkgs.jq}/bin/jq '."virtual-size"')" \
+         --arg boot_mode "${amiBootMode}" \
          --arg root "$rootDisk" \
          --arg boot "$bootDisk" \
         '{}
           | .label = $system_label
+          | .boot_mode = $boot_mode
           | .system = $system
           | .disks.boot.logical_bytes = $boot_logical_bytes
           | .disks.boot.file = $boot
@@ -145,9 +148,11 @@ in {
          --arg system_label ${lib.escapeShellArg config.system.nixos.label} \
          --arg system ${lib.escapeShellArg pkgs.stdenv.hostPlatform.system} \
          --arg logical_bytes "$(${pkgs.qemu}/bin/qemu-img info --output json "$diskImage" | ${pkgs.jq}/bin/jq '."virtual-size"')" \
+         --arg boot_mode "${amiBootMode}" \
          --arg file "$diskImage" \
           '{}
           | .label = $system_label
+          | .boot_mode = $boot_mode
           | .system = $system
           | .logical_bytes = $logical_bytes
           | .file = $file
diff --git a/nixos/maintainers/scripts/ec2/create-amis.sh b/nixos/maintainers/scripts/ec2/create-amis.sh
index 355894587391..1df27e2db55a 100755
--- a/nixos/maintainers/scripts/ec2/create-amis.sh
+++ b/nixos/maintainers/scripts/ec2/create-amis.sh
@@ -275,6 +275,7 @@ upload_image() {
                 --region "$region" \
                 --architecture $amazon_arch \
                 --block-device-mappings "${block_device_mappings[@]}" \
+                --boot-mode $(read_image_info .boot_mode) \
                 "${extra_flags[@]}" \
                 | jq -r '.ImageId'
               )