From 14f1c4f735471dd2fb683ec96c79988f6003a174 Mon Sep 17 00:00:00 2001
From: Jeremi Piotrowski <jpiotrowski@microsoft.com>
Date: Thu, 25 Apr 2024 10:22:58 +0000
Subject: [PATCH] grub_install: Remove core.{elf,efi} after copying

We currently carry multiple copies of the same grub core.elf or core.efi
on the boot partition. Save some space by removing duplicates that are
never used at runtime. CPIO build needed to be adapted because it
publishes grub efi files.

Signed-off-by: Jeremi Piotrowski <jpiotrowski@microsoft.com>
---
 build_library/grub_install.sh  | 9 +++++----
 build_library/vm_image_util.sh | 8 ++++----
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/build_library/grub_install.sh b/build_library/grub_install.sh
index d6f186f48b..6661e021d8 100755
--- a/build_library/grub_install.sh
+++ b/build_library/grub_install.sh
@@ -204,8 +204,9 @@ case "${FLAGS_target}" in
             sudo sbsign --key /usr/share/sb_keys/shim.key \
                 --cert /usr/share/sb_keys/shim.pem \
                 "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}"
-            sudo cp "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}.signed" \
+            sudo mv "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}.signed" \
                 "${ESP_DIR}/EFI/boot/grubx64.efi"
+            sudo rm "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}"
             # Sign the mokmanager(mm) with the shim-embedded key
             sudo sbsign --key /usr/share/sb_keys/shim.key \
                 --cert /usr/share/sb_keys/shim.pem \
@@ -218,7 +219,7 @@ case "${FLAGS_target}" in
                 --output "${ESP_DIR}/EFI/boot/bootx64.efi" \
                 "/usr/lib/shim/shim.efi"
         else
-            sudo cp "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}" \
+            sudo mv "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}" \
                 "${ESP_DIR}/EFI/boot/grubx64.efi"
             sudo cp "/usr/lib/shim/shim.efi" \
                 "${ESP_DIR}/EFI/boot/bootx64.efi"
@@ -238,7 +239,7 @@ case "${FLAGS_target}" in
     x86_64-xen)
         info "Installing default x86_64 Xen bootloader."
         sudo mkdir -p "${ESP_DIR}/xen" "${ESP_DIR}/boot/grub"
-        sudo cp "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}" \
+        sudo mv "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}" \
             "${ESP_DIR}/xen/pvboot-x86_64.elf"
         sudo cp "${BUILD_LIBRARY_DIR}/menu.lst" \
             "${ESP_DIR}/boot/grub/menu.lst"
@@ -247,7 +248,7 @@ case "${FLAGS_target}" in
         info "Installing default arm64 UEFI bootloader."
         sudo mkdir -p "${ESP_DIR}/EFI/boot"
         #FIXME(andrejro): shim not ported to aarch64
-        sudo cp "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}" \
+        sudo mv "${ESP_DIR}/${GRUB_DIR}/${CORE_NAME}" \
             "${ESP_DIR}/EFI/boot/bootaa64.efi"
         if [[ -n "${FLAGS_copy_efi_grub}" ]]; then
             # copying from vfat so ignore permissions
diff --git a/build_library/vm_image_util.sh b/build_library/vm_image_util.sh
index cd0a3745a5..b067362fc9 100644
--- a/build_library/vm_image_util.sh
+++ b/build_library/vm_image_util.sh
@@ -728,13 +728,13 @@ _write_cpio_disk() {
     # Pull the kernel and loader out of the filesystem
     ln -fs flatcar_production_image.vmlinuz "${dst_dir}/${vmlinuz_name}"
 
-    local grub_arch
+    local efi_file
     case $BOARD in
-        amd64-usr) grub_arch="x86_64-efi" ;;
-        arm64-usr) grub_arch="arm64-efi" ;;
+        amd64-usr) efi_file="grubx64.efi" ;;
+        arm64-usr) efi_file="bootaa64.efi" ;;
     esac
 
-    cp "${base_dir}/boot/flatcar/grub/${grub_arch}/core.efi" "${dst_dir}/${grub_name}"
+    cp "${base_dir}/boot/EFI/boot/${efi_file}" "${dst_dir}/${grub_name}"
     VM_GENERATED_FILES+=( "${dst_dir}/${vmlinuz_name}" "${dst_dir}/${grub_name}" )
 }