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Date: Sun,  3 Sep 2017 13:07:51 +0100
From: Ard Biesheuvel <ard.biesheuvel@...aro.org>
To: linux-arm-kernel@...ts.infradead.org,
	kernel-hardening@...ts.openwall.com
Cc: Ard Biesheuvel <ard.biesheuvel@...aro.org>,
	Arnd Bergmann <arnd@...db.de>,
	Nicolas Pitre <nico@...aro.org>,
	Russell King <linux@...linux.org.uk>,
	Kees Cook <keescook@...omium.org>,
	Thomas Garnier <thgarnie@...gle.com>,
	Marc Zyngier <marc.zyngier@....com>,
	Mark Rutland <mark.rutland@....com>,
	Tony Lindgren <tony@...mide.com>,
	Matt Fleming <matt@...eblueprint.co.uk>,
	Dave Martin <dave.martin@....com>
Subject: [PATCH v2 23/29] ARM: kernel: refer to swapper_pg_dir via its symbol

The location of swapper_pg_dir is relative to the kernel, not to
PAGE_OFFSET or PHYS_OFFSET. So define the symbol relative to the
start of the kernel image, and refer to it via its name.

Cc: Russell King <linux@...linux.org.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@...aro.org>
---
 arch/arm/kernel/head.S | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 5d685e86148c..71bc0d037bc9 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -48,14 +48,6 @@
 #define PMD_ORDER	2
 #endif
 
-	.globl	swapper_pg_dir
-	.equ	swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE
-
-	.macro	pgtbl, rd, phys
-	add	\rd, \phys, #TEXT_OFFSET
-	sub	\rd, \rd, #PG_DIR_SIZE
-	.endm
-
 /*
  * Kernel startup entry point.
  * ---------------------------
@@ -77,6 +69,9 @@
 	.arm
 
 	__HEAD
+	.globl	swapper_pg_dir
+	.equ	swapper_pg_dir, . - PG_DIR_SIZE
+
 ENTRY(stext)
  ARM_BE8(setend	be )			@ ensure we are in BE8 mode
 
@@ -172,7 +167,7 @@ ENDPROC(stext)
  *  r4 = physical page table address
  */
 __create_page_tables:
-	pgtbl	r4, r8				@ page table address
+	adr_l	r4, swapper_pg_dir		@ page table address
 
 	/*
 	 * Clear the swapper page table
-- 
2.11.0

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