File 0001-linux-fallback-to-EFI-handover-on-x86_64.patch of Package grub2

From 669b86cb7431b8d5df3490cb4cdc12545bfc3eea Mon Sep 17 00:00:00 2001
From: Michael Chang <mchang@suse.com>
Date: Sat, 26 Apr 2025 15:07:36 +0800
Subject: [PATCH 1/4] linux: fallback to EFI handover on x86_64

On the x86_64 platform, when the shim loader protocol is unavailable and
UEFI Secure Boot is enabled, fall back to the Linux EFI handover boot
protocol. This legacy method supports the in-kernel EFI stub and is used
instead of the 32-bit boot entry.

Signed-off-by: Michael Chang <mchang@suse.com>
---
 grub-core/Makefile.core.def       |  2 ++
 grub-core/loader/efi/linux.c      | 13 +++++++------
 grub-core/loader/i386/efi/linux.c | 30 ++++--------------------------
 3 files changed, 13 insertions(+), 32 deletions(-)

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 60d65b3206..62aa5ae58b 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -1895,6 +1895,8 @@ module = {
   loongarch64 = loader/efi/linux.c;
   riscv32 = loader/efi/linux.c;
   riscv64 = loader/efi/linux.c;
+  i386_efi = loader/efi/linux.c;
+  x86_64_efi = loader/efi/linux.c;
   emu = loader/emu/linux.c;
   common = loader/linux.c;
   i386_efi = loader/efi/linux_boot.c;
diff --git a/grub-core/loader/efi/linux.c b/grub-core/loader/efi/linux.c
index 69cab4e09b..4596185808 100644
--- a/grub-core/loader/efi/linux.c
+++ b/grub-core/loader/efi/linux.c
@@ -71,10 +71,10 @@ static initrd_media_device_path_t initrd_lf2_device_path = {
 };
 
 extern grub_err_t
-grub_cmd_linux_x86_legacy (grub_command_t cmd, int argc, char *argv[]);
+grub_cmd_linux_efi_fallback (grub_command_t cmd, int argc, char *argv[]);
 
 extern grub_err_t
-grub_cmd_initrd_x86_legacy (grub_command_t cmd, int argc, char *argv[]);
+grub_cmd_initrd_efi_fallback (grub_command_t cmd, int argc, char *argv[]);
 
 static grub_efi_status_t __grub_efi_api
 grub_efi_initrd_load_file2 (grub_efi_load_file2_t *this,
@@ -384,8 +384,9 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
     }
 
 #if defined(__i386__) || defined(__x86_64__)
-  if (!initrd_use_loadfile2)
-    return grub_cmd_initrd_x86_legacy (cmd, argc, argv);
+  if (grub_is_using_legacy_shim_lock_protocol () == true ||
+      !initrd_use_loadfile2)
+    return grub_cmd_initrd_efi_fallback (cmd, argc, argv);
 #endif
 
   if (!loaded)
@@ -469,7 +470,7 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
 #if defined(__i386__) || defined(__x86_64__)
       grub_dprintf ("linux", "using legacy shim_lock protocol, falling back to legacy Linux kernel loader\n");
 
-      err = grub_cmd_linux_x86_legacy (cmd, argc, argv);
+      err = grub_cmd_linux_efi_fallback (cmd, argc, argv);
 
       if (err == GRUB_ERR_NONE)
 	return GRUB_ERR_NONE;
@@ -508,7 +509,7 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
        */
 fallback:
       grub_file_close (file);
-      return grub_cmd_linux_x86_legacy (cmd, argc, argv);
+      return grub_cmd_linux_efi_fallback (cmd, argc, argv);
     }
 #endif
 
diff --git a/grub-core/loader/i386/efi/linux.c b/grub-core/loader/i386/efi/linux.c
index ca3435a884..49e4a3f198 100644
--- a/grub-core/loader/i386/efi/linux.c
+++ b/grub-core/loader/i386/efi/linux.c
@@ -421,30 +421,8 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
   return grub_errno;
 }
 
-static grub_command_t cmd_linux, cmd_initrd;
-static grub_command_t cmd_linuxefi, cmd_initrdefi;
+extern grub_err_t __attribute__((alias("grub_cmd_linux")))
+grub_cmd_linux_efi_fallback (grub_command_t cmd, int argc, char *argv[]);
 
-GRUB_MOD_INIT(linux)
-{
-  cmd_linuxefi =
-    grub_register_command ("linuxefi", grub_cmd_linux,
-                           0, N_("Load Linux."));
-  cmd_initrdefi =
-    grub_register_command ("initrdefi", grub_cmd_initrd,
-                           0, N_("Load initrd."));
-  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_linuxefi);
-  grub_unregister_command (cmd_initrdefi);
-  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[]);
-- 
2.49.0