Commit d61947a1 authored by Will Deacon's avatar Will Deacon Committed by Russell King
Browse files

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



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.

Cc: <stable@vger.kernel.org>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Tested-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 904464b9

arch/arm/kernel/head.S

+22 −4
Original line number Diff line number Diff line
@@ -184,13 +184,22 @@ __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
@@ -258,6 +267,11 @@ __create_page_tables: 
	addne	r6, r6, #1 << SECTION_SHIFT

	strne	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)

	/*
@@ -276,13 +290,17 @@ __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 */

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