File 0002-linux-fallback-to-direct-PE-entry-boot-on-arm64.patch of Package grub2

From eab0d82f874298966a9f664d7289c4ca6751fc19 Mon Sep 17 00:00:00 2001
From: Michael Chang <mchang@suse.com>
Date: Sat, 26 Apr 2025 15:33:28 +0800
Subject: [PATCH 2/4] linux: fallback to direct PE entry boot on arm64

On the arm64 platform, when the shim loader protocol is unavailable and
UEFI Secure Boot is enabled, fall back to booting via the direct PE/COFF
image entry point instead of requesting UEFI to load and start the
image. This fallback allows booting binaries validated by shim's vendor
DB, even if they are not listed in the UEFI DB.

Signed-off-by: Michael Chang <mchang@suse.com>
---
 grub-core/Makefile.core.def        |  1 +
 grub-core/loader/arm64/efi/linux.c | 26 +++++++-------------------
 grub-core/loader/efi/linux.c       |  6 +++---
 3 files changed, 11 insertions(+), 22 deletions(-)

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 62aa5ae58b..303519a6f1 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -1891,6 +1891,7 @@ module = {
   arm_coreboot = loader/arm/linux.c;
   arm_efi = loader/efi/linux.c;
   arm_uboot = loader/arm/linux.c;
+  arm64 = loader/efi/linux.c;
   arm64 = loader/arm64/efi/linux.c;
   loongarch64 = loader/efi/linux.c;
   riscv32 = loader/efi/linux.c;
diff --git a/grub-core/loader/arm64/efi/linux.c b/grub-core/loader/arm64/efi/linux.c
index a9f5e05e45..8eab1dc865 100644
--- a/grub-core/loader/arm64/efi/linux.c
+++ b/grub-core/loader/arm64/efi/linux.c
@@ -190,8 +190,8 @@ free_params (void)
     }
 }
 
-grub_err_t
-grub_arch_efi_linux_boot_image (grub_addr_t addr,
+static grub_err_t
+grub_arm64_efi_linux_boot_image (grub_addr_t addr,
 			        grub_size_t size __attribute__ ((unused)),
 			        char *args)
 {
@@ -213,7 +213,7 @@ grub_arch_efi_linux_boot_image (grub_addr_t addr,
 static grub_err_t
 grub_linux_boot (void)
 {
-  return (grub_arch_efi_linux_boot_image ((grub_addr_t)kernel_addr, kernel_size, linux_args));
+  return (grub_arm64_efi_linux_boot_image ((grub_addr_t)kernel_addr, kernel_size, linux_args));
 }
 
 static grub_err_t
@@ -464,20 +464,8 @@ fail:
   return grub_errno;
 }
 
+extern grub_err_t __attribute__((alias("grub_cmd_linux")))
+grub_cmd_linux_efi_fallback (grub_command_t cmd, int argc, char *argv[]);
 
-static grub_command_t cmd_linux, cmd_initrd;
-
-GRUB_MOD_INIT (linux)
-{
-  cmd_linux = grub_register_command ("linux", grub_cmd_linux, 0,
-				     N_("Load Linux."));
-  cmd_initrd = grub_register_command ("initrd", grub_cmd_initrd, 0,
-				      N_("Load initrd."));
-  my_mod = mod;
-}
-
-GRUB_MOD_FINI (linux)
-{
-  grub_unregister_command (cmd_linux);
-  grub_unregister_command (cmd_initrd);
-}
+extern grub_err_t __attribute__((alias("grub_cmd_initrd")))
+grub_cmd_initrd_efi_fallback (grub_command_t cmd, int argc, char *argv[]);
diff --git a/grub-core/loader/efi/linux.c b/grub-core/loader/efi/linux.c
index 4596185808..f319811838 100644
--- a/grub-core/loader/efi/linux.c
+++ b/grub-core/loader/efi/linux.c
@@ -383,7 +383,7 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
       goto fail;
     }
 
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
   if (grub_is_using_legacy_shim_lock_protocol () == true ||
       !initrd_use_loadfile2)
     return grub_cmd_initrd_efi_fallback (cmd, argc, argv);
@@ -467,7 +467,7 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
 
   if (grub_is_using_legacy_shim_lock_protocol () == true)
     {
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__i386__) || defined(__x86_64__) || defined (__aarch64__)
       grub_dprintf ("linux", "using legacy shim_lock protocol, falling back to legacy Linux kernel loader\n");
 
       err = grub_cmd_linux_efi_fallback (cmd, argc, argv);
@@ -494,7 +494,7 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
   kernel_size = grub_file_size (file);
 
   if (grub_arch_efi_linux_load_image_header (file, &lh) != GRUB_ERR_NONE)
-#if !defined(__i386__) && !defined(__x86_64__)
+#if !defined(__i386__) && !defined(__x86_64__) && !defined (__aarch64__)
     goto fail;
 #else
     goto fallback;
-- 
2.49.0