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commit 69edb31205602c29293a8c6e67363bba2a4a1e66
Author: Ard Biesheuvel <ardb@kernel.org>
Date:   Thu Aug 11 16:51:57 2022 +0200

    loader/arm64/linux: Remove magic number header field check
    
    The "ARM\x64" magic number in the file header identifies an image as one
    that implements the bare metal boot protocol, allowing the loader to
    simply move the file to a suitably aligned address in memory, with
    sufficient headroom for the trailing .bss segment (the required memory
    size is described in the header as well).
    
    Note of this matters for GRUB, as it only supports EFI boot. EFI does
    not care about this magic number, and nor should GRUB: this prevents us
    from booting other PE linux images, such as the generic EFI zboot
    decompressor, which is a pure PE/COFF image, and does not implement the
    bare metal boot protocol.
    
    So drop the magic number check.
    
    Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
    Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

diff --git a/grub-core/loader/arm64/linux.c b/grub-core/loader/arm64/linux.c
index ef3e9f944..4c92e48ac 100644
--- a/grub-core/loader/arm64/linux.c
+++ b/grub-core/loader/arm64/linux.c
@@ -51,9 +51,6 @@ static grub_addr_t initrd_end;
 grub_err_t
 grub_arch_efi_linux_check_image (struct linux_arch_kernel_header * lh)
 {
-  if (lh->magic != GRUB_LINUX_ARMXX_MAGIC_SIGNATURE)
-    return grub_error(GRUB_ERR_BAD_OS, "invalid magic number");
-
   if ((lh->code0 & 0xffff) != GRUB_PE32_MAGIC)
     return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
 		       N_("plain image kernel not supported - rebuild with CONFIG_(U)EFI_STUB enabled"));