From d635711daa98be86d4c7fd01499c34f566b54ccb Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Fri, 10 Jun 2016 05:30:17 -0300
Subject: Linux-libre 4.6.2-gnu

---
 arch/arm64/kernel/image.h | 45 +++++++++++++++++++++++++++------------------
 1 file changed, 27 insertions(+), 18 deletions(-)

(limited to 'arch/arm64/kernel/image.h')

diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h
index 352f7abd9..5e360ce88 100644
--- a/arch/arm64/kernel/image.h
+++ b/arch/arm64/kernel/image.h
@@ -26,31 +26,40 @@
  * There aren't any ELF relocations we can use to endian-swap values known only
  * at link time (e.g. the subtraction of two symbol addresses), so we must get
  * the linker to endian-swap certain values before emitting them.
+ *
+ * Note that, in order for this to work when building the ELF64 PIE executable
+ * (for KASLR), these values should not be referenced via R_AARCH64_ABS64
+ * relocations, since these are fixed up at runtime rather than at build time
+ * when PIE is in effect. So we need to split them up in 32-bit high and low
+ * words.
  */
 #ifdef CONFIG_CPU_BIG_ENDIAN
-#define DATA_LE64(data)					\
-	((((data) & 0x00000000000000ff) << 56) |	\
-	 (((data) & 0x000000000000ff00) << 40) |	\
-	 (((data) & 0x0000000000ff0000) << 24) |	\
-	 (((data) & 0x00000000ff000000) << 8)  |	\
-	 (((data) & 0x000000ff00000000) >> 8)  |	\
-	 (((data) & 0x0000ff0000000000) >> 24) |	\
-	 (((data) & 0x00ff000000000000) >> 40) |	\
-	 (((data) & 0xff00000000000000) >> 56))
+#define DATA_LE32(data)				\
+	((((data) & 0x000000ff) << 24) |	\
+	 (((data) & 0x0000ff00) << 8)  |	\
+	 (((data) & 0x00ff0000) >> 8)  |	\
+	 (((data) & 0xff000000) >> 24))
 #else
-#define DATA_LE64(data) ((data) & 0xffffffffffffffff)
+#define DATA_LE32(data) ((data) & 0xffffffff)
 #endif
 
+#define DEFINE_IMAGE_LE64(sym, data)				\
+	sym##_lo32 = DATA_LE32((data) & 0xffffffff);		\
+	sym##_hi32 = DATA_LE32((data) >> 32)
+
 #ifdef CONFIG_CPU_BIG_ENDIAN
-#define __HEAD_FLAG_BE	1
+#define __HEAD_FLAG_BE		1
 #else
-#define __HEAD_FLAG_BE	0
+#define __HEAD_FLAG_BE		0
 #endif
 
-#define __HEAD_FLAG_PAGE_SIZE ((PAGE_SHIFT - 10) / 2)
+#define __HEAD_FLAG_PAGE_SIZE	((PAGE_SHIFT - 10) / 2)
+
+#define __HEAD_FLAG_PHYS_BASE	1
 
-#define __HEAD_FLAGS	((__HEAD_FLAG_BE << 0) |	\
-			 (__HEAD_FLAG_PAGE_SIZE << 1))
+#define __HEAD_FLAGS		((__HEAD_FLAG_BE << 0) |	\
+				 (__HEAD_FLAG_PAGE_SIZE << 1) |	\
+				 (__HEAD_FLAG_PHYS_BASE << 3))
 
 /*
  * These will output as part of the Image header, which should be little-endian
@@ -58,9 +67,9 @@
  * endian swapped in head.S, all are done here for consistency.
  */
 #define HEAD_SYMBOLS						\
-	_kernel_size_le		= DATA_LE64(_end - _text);	\
-	_kernel_offset_le	= DATA_LE64(TEXT_OFFSET);	\
-	_kernel_flags_le	= DATA_LE64(__HEAD_FLAGS);
+	DEFINE_IMAGE_LE64(_kernel_size_le, _end - _text);	\
+	DEFINE_IMAGE_LE64(_kernel_offset_le, TEXT_OFFSET);	\
+	DEFINE_IMAGE_LE64(_kernel_flags_le, __HEAD_FLAGS);
 
 #ifdef CONFIG_EFI
 
-- 
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