[PATCH for-stable-6.1 09/23] x86/boot: Grab kernel_info offset from zoffset header directly

[Ard Biesheuvel <ardb+git@google.com>]

From: Ard Biesheuvel <ardb@kernel.org>

[ Commit 2e765c02dcbfc2a8a4527c621a84b9502f6b9bd2 upstream ]

Instead of parsing zoffset.h and poking the kernel_info offset value
into the header from the build tool, just grab the value directly in the
asm file that describes this header.

This change has no impact on the resulting bzImage binary.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230915171623.655440-11-ardb@google.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/x86/boot/header.S      | 2 +-
 arch/x86/boot/tools/build.c | 4 ----
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index f63bf3ec6869..becf39d8115c 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -525,7 +525,7 @@ pref_address:		.quad LOAD_PHYSICAL_ADDR	# preferred load addr
 
 init_size:		.long INIT_SIZE		# kernel initialization size
 handover_offset:	.long 0			# Filled in by build.c
-kernel_info_offset:	.long 0			# Filled in by build.c
+kernel_info_offset:	.long ZO_kernel_info
 
 # End of setup header #####################################################
 
diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
index 10b0207a6b18..14ef13fe7ab0 100644
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -59,7 +59,6 @@ static unsigned long efi32_stub_entry;
 static unsigned long efi64_stub_entry;
 static unsigned long efi_pe_entry;
 static unsigned long efi32_pe_entry;
-static unsigned long kernel_info;
 static unsigned long _end;
 
 /*----------------------------------------------------------------------*/
@@ -337,7 +336,6 @@ static void parse_zoffset(char *fname)
 		PARSE_ZOFS(p, efi64_stub_entry);
 		PARSE_ZOFS(p, efi_pe_entry);
 		PARSE_ZOFS(p, efi32_pe_entry);
-		PARSE_ZOFS(p, kernel_info);
 		PARSE_ZOFS(p, _end);
 
 		p = strchr(p, '\n');
@@ -419,8 +417,6 @@ int main(int argc, char ** argv)
 	update_pecoff_text(setup_sectors * 512, i + (sys_size * 16));
 
 	efi_stub_entry_update();
-	/* Update kernel_info offset. */
-	put_unaligned_le32(kernel_info, &buf[0x268]);
 
 	crc = partial_crc32(buf, i, crc);
 	if (fwrite(buf, 1, i, dest) != i)
-- 
2.44.0.769.g3c40516874-goog