Patchwork [3.5.y.z,extended,stable] Patch "ARM: 7657/1: head: fix swapper and idmap population with LPAE" has been added to staging queue

login
register
mail settings
Submitter Luis Henriques
Date March 11, 2013, 12:07 p.m.
Message ID <1363003662-3106-1-git-send-email-luis.henriques@canonical.com>
Download mbox | patch
Permalink /patch/226542/
State New
Headers show

Comments

Luis Henriques - March 11, 2013, 12:07 p.m.
This is a note to let you know that I have just added a patch titled

    ARM: 7657/1: head: fix swapper and idmap population with LPAE

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

From d9de95e95e3d5ea3fee04058495b3aae1beeb82c Mon Sep 17 00:00:00 2001
From: Will Deacon <will.deacon@arm.com>
Date: Thu, 28 Feb 2013 17:46:16 +0100
Subject: [PATCH] ARM: 7657/1: head: fix swapper and idmap population with LPAE
 and big-endian

commit d61947a164760ac520cb416768afdf38c33d60e7 upstream.

The LPAE page table format uses 64-bit descriptors, so we need to take
endianness into account when populating the swapper and idmap tables
during early initialisation.

This patch ensures that we store the two words making up each page table
entry in the correct order when running big-endian.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 arch/arm/kernel/head.S | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

--
1.8.1.2

Patch

diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 458b8d3..f47f770 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -188,13 +188,22 @@  __create_page_tables:
 	orr	r3, r3, #3			@ PGD block type
 	mov	r6, #4				@ PTRS_PER_PGD
 	mov	r7, #1 << (55 - 32)		@ L_PGD_SWAPPER
-1:	str	r3, [r0], #4			@ set bottom PGD entry bits
+1:
+#ifdef CONFIG_CPU_ENDIAN_BE8
 	str	r7, [r0], #4			@ set top PGD entry bits
+	str	r3, [r0], #4			@ set bottom PGD entry bits
+#else
+	str	r3, [r0], #4			@ set bottom PGD entry bits
+	str	r7, [r0], #4			@ set top PGD entry bits
+#endif
 	add	r3, r3, #0x1000			@ next PMD table
 	subs	r6, r6, #1
 	bne	1b

 	add	r4, r4, #0x1000			@ point to the PMD tables
+#ifdef CONFIG_CPU_ENDIAN_BE8
+	add	r4, r4, #4			@ we only write the bottom word
+#endif
 #endif

 	ldr	r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags
@@ -267,6 +276,11 @@  __create_page_tables:
 	add	r6, r6, #1 << SECTION_SHIFT
 	str	r6, [r3]

+#if defined(CONFIG_LPAE) && defined(CONFIG_CPU_ENDIAN_BE8)
+	sub	r4, r4, #4			@ Fixup page table pointer
+						@ for 64-bit descriptors
+#endif
+
 #ifdef CONFIG_DEBUG_LL
 #if !defined(CONFIG_DEBUG_ICEDCC) && !defined(CONFIG_DEBUG_SEMIHOSTING)
 	/*
@@ -285,13 +299,17 @@  __create_page_tables:
 	orr	r3, r7, r3, lsl #SECTION_SHIFT
 #ifdef CONFIG_ARM_LPAE
 	mov	r7, #1 << (54 - 32)		@ XN
+#ifdef CONFIG_CPU_ENDIAN_BE8
+	str	r7, [r0], #4
+	str	r3, [r0], #4
 #else
-	orr	r3, r3, #PMD_SECT_XN
-#endif
 	str	r3, [r0], #4
-#ifdef CONFIG_ARM_LPAE
 	str	r7, [r0], #4
 #endif
+#else
+	orr	r3, r3, #PMD_SECT_XN
+	str	r3, [r0], #4
+#endif

 #else /* CONFIG_DEBUG_ICEDCC || CONFIG_DEBUG_SEMIHOSTING */
 	/* we don't need any serial debugging mappings */