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Date: Wed,  8 Feb 2017 11:55:37 +0000
From: Ard Biesheuvel <ard.biesheuvel@...aro.org>
To: linux-efi@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	mark.rutland@....com,
	leif.lindholm@...aro.org
Cc: catalin.marinas@....com,
	linux@...linux.org.uk,
	kernel-hardening@...ts.openwall.com,
	labbott@...oraproject.org,
	Ard Biesheuvel <ard.biesheuvel@...aro.org>
Subject: [PATCH v2 04/14] arm64: efi: clean up Image header after PE header has been split off

After having split off the PE header, clean up the bits that remain:
use .long consistently, merge two adjacent #ifdef CONFIG_EFI blocks,
fix the offset of the PE header pointer and remove the redundant .align
that follows it.

Also, since we will be eliminating all open coded constants from the
EFI header in subsequent patches, let's replace the open coded "ARM\x64"
magic number with its .ascii equivalent.

No changes to the resulting binary image are intended.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@...aro.org>
---
 arch/arm64/kernel/head.S | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index f779a7483736..aa8f6cd8c33f 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -91,20 +91,19 @@ _head:
 	.quad	0				// reserved
 	.quad	0				// reserved
 	.quad	0				// reserved
-	.byte	0x41				// Magic number, "ARM\x64"
-	.byte	0x52
-	.byte	0x4d
-	.byte	0x64
+	.ascii	"ARM\x64"			// Magic number
 #ifdef CONFIG_EFI
+	/*
+	 * PE/COFF requires the offset to the PE header
+	 * to be stored at offset 0x3c into the file.
+	 */
+	.org	_head + 0x3c
 	.long	pe_header - _head		// Offset to the PE header.
-#else
-	.word	0				// reserved
-#endif
 
-#ifdef CONFIG_EFI
-	.align 3
 pe_header:
 	__EFI_PE_HEADER
+#else
+	.long	0				// reserved
 #endif
 
 	__INIT
-- 
2.7.4

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