[RESEND PATCH v4 0/6] arm64/mm: Move

[RESEND PATCH v4 0/6] arm64/mm: Move

[Jun Yao]

Version 4 changes:
	1. Rename INIT_DIR to INIT_PG_TABLES and move it outside the
	   '.init.data' section[1].
	2. Move the 'count' calculation to clear_pages()[1].
	3. Rearrange register in __enable_mmu() and pass ttbr1 through
	   the x1 register[2].
	4. Add commit message to explain why we can make swapper_pg_dir
	   smaller[3].
	5. Rewrite in_swapper_pgdir() and use pgd_set_fixmap() to
	   populate swapper_pg_dir. At the same time, add a spin lock to
	   avoid race conditions[4].
	6. Move {idmap_pg_dir,tramp_pg_dir,reserved_ttbr0,swapper_pg_dir}
	   to the KERNEL_PG_TABLES macro. And put this macro after
	   NOTES[4].
	7. Update init_mm.pgd before kasan_early_init() and
           kaslr_early_init(), which makes pgd_offset_k() work properly.

Test following configs with CONFIG_RANDOMIZE_BASE/UNMAP_KERNEL_AT_EL0/
CONFIG_ARM64_SW_TTBR0_PAN enabled on qemu:

	1. CONFIG_ARM64_4K_PAGES/CONFIG_ARM64_VA_BITS_48
	2. CONFIG_ARM64_4K_PAGES/CONFIG_ARM64_VA_BITS_39
	3. CONFIG_ARM64_64K_PAGES/CONFIG_ARM64_VA_BITS_48
	4. CONFIG_ARM64_64K_PAGES/CONFIG_ARM64_VA_BITS_42

v3: https://www.spinics.net/lists/arm-kernel/msg662537.html
v2: https://patchwork.kernel.org/patch/10485641/
v1: https://patchwork.kernel.org/patch/10476595/

[1] https://lkml.org/lkml/2018/7/6/238
[2] https://lkml.org/lkml/2018/7/6/239
[3] https://lkml.org/lkml/2018/7/6/243
[4] https://lkml.org/lkml/2018/7/11/782

Jun Yao (6):
  arm64/mm: Introduce init_pg_dir
  arm64/mm: Make __enable_mmu() take the ttbr1 page as an argument
  arm64/mm: Create initial page tables in init_pg_dir
  arm64/mm: Make swapper_pg_dir smaller
  arm64/mm: Populate swapper_pg_dir by fixmap
  arm64/mm: Move {idmap_pg_dir, swapper_pg_dir} to .rodata section

 arch/arm64/include/asm/assembler.h | 29 +++++++++++++
 arch/arm64/include/asm/pgtable.h   | 66 ++++++++++++++++++++++++++----
 arch/arm64/kernel/head.S           | 48 ++++++++++++++--------
 arch/arm64/kernel/sleep.S          |  1 +
 arch/arm64/kernel/vmlinux.lds.S    | 47 ++++++++++++++-------
 arch/arm64/mm/mmu.c                | 35 ++++------------
 6 files changed, 159 insertions(+), 67 deletions(-)

-- 
2.17.1

[RESEND PATCH v4 1/6] arm64/mm: Introduce init_pg_dir

[Jun Yao]

Add init_pg_dir to vmlinux.lds.S and boiler-plate
clearing/cleaning/invalidating it in head.S.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
---
 arch/arm64/include/asm/assembler.h | 29 +++++++++++++++++++++++++++++
 arch/arm64/kernel/head.S           | 22 +++++++++++++++-------
 arch/arm64/kernel/vmlinux.lds.S    |  8 ++++++++
 3 files changed, 52 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 0bcc98dbba56..eb363a915c0e 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -456,6 +456,35 @@ USER(\label, ic	ivau, \tmp2)			// invalidate I line PoU
 	b.ne	9998b
 	.endm
 
+/*
+ * clear_page - clear one page
+ *
+ *	start:	page aligned virtual address
+ */
+	.macro clear_page, start:req
+9996:	stp	xzr, xzr, [\start], #16
+	stp	xzr, xzr, [\start], #16
+	stp	xzr, xzr, [\start], #16
+	stp	xzr, xzr, [\start], #16
+	tst	\start, #(PAGE_SIZE - 1)
+	b.ne	9996b
+	.endm
+
+/*
+ * clear_pages - clear contiguous pages
+ *
+ *	start, end: page aligend virtual addresses
+ */
+	.macro clear_pages, start:req, end:req
+	sub	\end, \end, \start
+	lsr	\end, \end, #(PAGE_SHIFT)
+9997:	cbz	\end, 9998f
+	clear_page \start
+	sub	\end, \end, #1
+	b	9997b
+9998:
+	.endm
+
 /*
  * Annotate a function as position independent, i.e., safe to be called before
  * the kernel virtual mapping is activated.
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index b0853069702f..2c83a8c47e3f 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -295,18 +295,21 @@ __create_page_tables:
 	sub	x1, x1, x0
 	bl	__inval_dcache_area
 
+	adrp	x0, init_pg_dir
+	adrp	x1, init_pg_end
+	sub	x1, x1, x0
+	bl	__inval_dcache_area
+
 	/*
 	 * Clear the idmap and swapper page tables.
 	 */
 	adrp	x0, idmap_pg_dir
 	adrp	x1, swapper_pg_end
-	sub	x1, x1, x0
-1:	stp	xzr, xzr, [x0], #16
-	stp	xzr, xzr, [x0], #16
-	stp	xzr, xzr, [x0], #16
-	stp	xzr, xzr, [x0], #16
-	subs	x1, x1, #64
-	b.ne	1b
+	clear_pages x0, x1
+
+	adrp	x0, init_pg_dir
+	adrp	x1, init_pg_end
+	clear_pages x0, x1
 
 	mov	x7, SWAPPER_MM_MMUFLAGS
 
@@ -395,6 +398,11 @@ __create_page_tables:
 	dmb	sy
 	bl	__inval_dcache_area
 
+	adrp	x0, init_pg_dir
+	adrp	x1, init_pg_end
+	sub	x1, x1, x0
+	bl	__inval_dcache_area
+
 	ret	x28
 ENDPROC(__create_page_tables)
 	.ltorg
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 605d1b60469c..61d7cee3eaa6 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -68,6 +68,12 @@ jiffies = jiffies_64;
 #define TRAMP_TEXT
 #endif
 
+#define INIT_PG_TABLES					\
+	. = ALIGN(PAGE_SIZE);                           \
+	init_pg_dir = .;                                \
+	. += SWAPPER_DIR_SIZE;                          \
+	init_pg_end = .;
+
 /*
  * The size of the PE/COFF section that covers the kernel image, which
  * runs from stext to _edata, must be a round multiple of the PE/COFF
@@ -161,6 +167,8 @@ SECTIONS
 	__inittext_end = .;
 	__initdata_begin = .;
 
+	INIT_PG_TABLES
+
 	.init.data : {
 		INIT_DATA
 		INIT_SETUP(16)
-- 
2.17.1

[RESEND PATCH v4 2/6] arm64/mm: Make __enable_mmu() take the

[Jun Yao]

Make __enable_mmu() take the physical address of the ttbr1 page as
an argument.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
---
 arch/arm64/kernel/head.S  | 21 ++++++++++++---------
 arch/arm64/kernel/sleep.S |  1 +
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 2c83a8c47e3f..c3e4b1886cde 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -714,6 +714,7 @@ secondary_startup:
 	 * Common entry point for secondary CPUs.
 	 */
 	bl	__cpu_setup			// initialise processor
+	adrp	x1, swapper_pg_dir
 	bl	__enable_mmu
 	ldr	x8, =__secondary_switched
 	br	x8
@@ -756,6 +757,7 @@ ENDPROC(__secondary_switched)
  * Enable the MMU.
  *
  *  x0  = SCTLR_EL1 value for turning on the MMU.
+ *  x1  = TTBR1_EL1 value for turning on the MMU.
  *
  * Returns to the caller via x30/lr. This requires the caller to be covered
  * by the .idmap.text section.
@@ -764,15 +766,15 @@ ENDPROC(__secondary_switched)
  * If it isn't, park the CPU
  */
 ENTRY(__enable_mmu)
-	mrs	x1, ID_AA64MMFR0_EL1
-	ubfx	x2, x1, #ID_AA64MMFR0_TGRAN_SHIFT, 4
-	cmp	x2, #ID_AA64MMFR0_TGRAN_SUPPORTED
+	mrs	x5, ID_AA64MMFR0_EL1
+	ubfx	x6, x5, #ID_AA64MMFR0_TGRAN_SHIFT, 4
+	cmp	x6, #ID_AA64MMFR0_TGRAN_SUPPORTED
 	b.ne	__no_granule_support
-	update_early_cpu_boot_status 0, x1, x2
-	adrp	x1, idmap_pg_dir
-	adrp	x2, swapper_pg_dir
-	phys_to_ttbr x3, x1
-	phys_to_ttbr x4, x2
+	update_early_cpu_boot_status 0, x5, x6
+	adrp	x5, idmap_pg_dir
+	mov	x6, x1
+	phys_to_ttbr x3, x5
+	phys_to_ttbr x4, x6
 	msr	ttbr0_el1, x3			// load TTBR0
 	msr	ttbr1_el1, x4			// load TTBR1
 	isb
@@ -791,7 +793,7 @@ ENDPROC(__enable_mmu)
 
 __no_granule_support:
 	/* Indicate that this CPU can't boot and is stuck in the kernel */
-	update_early_cpu_boot_status CPU_STUCK_IN_KERNEL, x1, x2
+	update_early_cpu_boot_status CPU_STUCK_IN_KERNEL, x5, x6
 1:
 	wfe
 	wfi
@@ -831,6 +833,7 @@ __primary_switch:
 	mrs	x20, sctlr_el1			// preserve old SCTLR_EL1 value
 #endif
 
+	adrp	x1, swapper_pg_dir
 	bl	__enable_mmu
 #ifdef CONFIG_RELOCATABLE
 	bl	__relocate_kernel
diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S
index bebec8ef9372..3e53ffa07994 100644
--- a/arch/arm64/kernel/sleep.S
+++ b/arch/arm64/kernel/sleep.S
@@ -101,6 +101,7 @@ ENTRY(cpu_resume)
 	bl	el2_setup		// if in EL2 drop to EL1 cleanly
 	bl	__cpu_setup
 	/* enable the MMU early - so we can access sleep_save_stash by va */
+	adrp	x1, swapper_pg_dir
 	bl	__enable_mmu
 	ldr	x8, =_cpu_resume
 	br	x8
-- 
2.17.1

[RESEND PATCH v4 3/6] arm64/mm: Create initial page tables in

[Jun Yao]

Create initial page tables in init_pg_dir and then create final
page tables in swapper_pg_dir directly.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
---
 arch/arm64/include/asm/pgtable.h |  2 ++
 arch/arm64/kernel/head.S         |  9 ++++++---
 arch/arm64/mm/mmu.c              | 27 ++++++++-------------------
 3 files changed, 16 insertions(+), 22 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 1bdeca8918a6..46ef21ebfe47 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -712,6 +712,8 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
 }
 #endif
 
+extern pgd_t init_pg_dir[PTRS_PER_PGD];
+extern pgd_t init_pg_end[];
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
 extern pgd_t swapper_pg_end[];
 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index c3e4b1886cde..ede2e964592b 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -376,7 +376,7 @@ __create_page_tables:
 	/*
 	 * Map the kernel image (starting with PHYS_OFFSET).
 	 */
-	adrp	x0, swapper_pg_dir
+	adrp	x0, init_pg_dir
 	mov_q	x5, KIMAGE_VADDR + TEXT_OFFSET	// compile time __va(_text)
 	add	x5, x5, x23			// add KASLR displacement
 	mov	x4, PTRS_PER_PGD
@@ -402,7 +402,6 @@ __create_page_tables:
 	adrp	x1, init_pg_end
 	sub	x1, x1, x0
 	bl	__inval_dcache_area
-
 	ret	x28
 ENDPROC(__create_page_tables)
 	.ltorg
@@ -439,6 +438,9 @@ __primary_switched:
 	bl	__pi_memset
 	dsb	ishst				// Make zero page visible to PTW
 
+	adrp	x0, init_pg_dir
+	bl	set_init_mm_pgd
+
 #ifdef CONFIG_KASAN
 	bl	kasan_early_init
 #endif
@@ -833,8 +835,9 @@ __primary_switch:
 	mrs	x20, sctlr_el1			// preserve old SCTLR_EL1 value
 #endif
 
-	adrp	x1, swapper_pg_dir
+	adrp	x1, init_pg_dir
 	bl	__enable_mmu
+
 #ifdef CONFIG_RELOCATABLE
 	bl	__relocate_kernel
 #ifdef CONFIG_RANDOMIZE_BASE
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 65f86271f02b..088a591e4ea4 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -629,26 +629,10 @@ static void __init map_kernel(pgd_t *pgdp)
  */
 void __init paging_init(void)
 {
-	phys_addr_t pgd_phys = early_pgtable_alloc();
-	pgd_t *pgdp = pgd_set_fixmap(pgd_phys);
-
-	map_kernel(pgdp);
-	map_mem(pgdp);
-
-	/*
-	 * We want to reuse the original swapper_pg_dir so we don't have to
-	 * communicate the new address to non-coherent secondaries in
-	 * secondary_entry, and so cpu_switch_mm can generate the address with
-	 * adrp+add rather than a load from some global variable.
-	 *
-	 * To do this we need to go via a temporary pgd.
-	 */
-	cpu_replace_ttbr1(__va(pgd_phys));
-	memcpy(swapper_pg_dir, pgdp, PGD_SIZE);
+	map_kernel(swapper_pg_dir);
+	map_mem(swapper_pg_dir);
 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
-
-	pgd_clear_fixmap();
-	memblock_free(pgd_phys, PAGE_SIZE);
+	init_mm.pgd = swapper_pg_dir;
 
 	/*
 	 * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd
@@ -659,6 +643,11 @@ void __init paging_init(void)
 		      - PAGE_SIZE);
 }
 
+void __init set_init_mm_pgd(pgd_t *pgd)
+{
+	init_mm.pgd = pgd;
+}
+
 /*
  * Check whether a kernel address is valid (derived from arch/x86/).
  */
-- 
2.17.1

[RESEND PATCH v4 4/6] arm64/mm: Make swapper_pg_dir smaller

[Jun Yao]

We setup final page tables in swapper_pg_dir, which just contains
PGD. And the PUD/PMD are allocated dynamically. So we can make it
smaller.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
---
 arch/arm64/kernel/vmlinux.lds.S | 2 +-
 arch/arm64/mm/mmu.c             | 8 --------
 2 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 61d7cee3eaa6..2446911f4262 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -237,7 +237,7 @@ SECTIONS
 	. += RESERVED_TTBR0_SIZE;
 #endif
 	swapper_pg_dir = .;
-	. += SWAPPER_DIR_SIZE;
+	. += PAGE_SIZE;
 	swapper_pg_end = .;
 
 	__pecoff_data_size = ABSOLUTE(. - __initdata_begin);
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 088a591e4ea4..1d16104aa0b9 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -633,14 +633,6 @@ void __init paging_init(void)
 	map_mem(swapper_pg_dir);
 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
 	init_mm.pgd = swapper_pg_dir;
-
-	/*
-	 * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd
-	 * allocated with it.
-	 */
-	memblock_free(__pa_symbol(swapper_pg_dir) + PAGE_SIZE,
-		      __pa_symbol(swapper_pg_end) - __pa_symbol(swapper_pg_dir)
-		      - PAGE_SIZE);
 }
 
 void __init set_init_mm_pgd(pgd_t *pgd)
-- 
2.17.1

[RESEND PATCH v4 5/6] arm64/mm: Populate swapper_pg_dir by

[Jun Yao]

To move swapper_pg_dir to .rodata section, we populate it by
fixmap.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
---
 arch/arm64/include/asm/pgtable.h | 68 ++++++++++++++++++++++++++------
 arch/arm64/mm/mmu.c              |  2 +
 2 files changed, 59 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 46ef21ebfe47..d5c3df99af7b 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -45,6 +45,13 @@
 #include <linux/mm_types.h>
 #include <linux/sched.h>
 
+extern pgd_t init_pg_dir[PTRS_PER_PGD];
+extern pgd_t init_pg_end[];
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern pgd_t swapper_pg_end[];
+extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
+extern pgd_t tramp_pg_dir[PTRS_PER_PGD];
+
 extern void __pte_error(const char *file, int line, unsigned long val);
 extern void __pmd_error(const char *file, int line, unsigned long val);
 extern void __pud_error(const char *file, int line, unsigned long val);
@@ -428,8 +435,32 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 				 PUD_TYPE_TABLE)
 #endif
 
+extern spinlock_t swapper_pgdir_lock;
+
+#define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
+#define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
+
+static inline bool in_swapper_pgdir(void *addr)
+{
+	return ((unsigned long)addr & PAGE_MASK) ==
+		((unsigned long)swapper_pg_dir & PAGE_MASK);
+}
+
 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 {
+#ifdef __PAGETABLE_PMD_FOLDED
+	if (in_swapper_pgdir(pmdp)) {
+		pmd_t *fixmap_pmdp;
+
+		spin_lock(&swapper_pgdir_lock);
+		fixmap_pmdp = (pmd_t *)pgd_set_fixmap(__pa(pmdp));
+		WRITE_ONCE(*fixmap_pmdp, pmd);
+		dsb(ishst);
+		pgd_clear_fixmap();
+		spin_unlock(&swapper_pgdir_lock);
+		return;
+	}
+#endif
 	WRITE_ONCE(*pmdp, pmd);
 	dsb(ishst);
 }
@@ -480,6 +511,19 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
 
 static inline void set_pud(pud_t *pudp, pud_t pud)
 {
+#ifdef __PAGETABLE_PUD_FOLDED
+	if (in_swapper_pgdir(pudp)) {
+		pud_t *fixmap_pudp;
+
+		spin_lock(&swapper_pgdir_lock);
+		fixmap_pudp = (pud_t *)pgd_set_fixmap(__pa(pudp));
+		WRITE_ONCE(*fixmap_pudp, pud);
+		dsb(ishst);
+		pgd_clear_fixmap();
+		spin_unlock(&swapper_pgdir_lock);
+		return;
+	}
+#endif
 	WRITE_ONCE(*pudp, pud);
 	dsb(ishst);
 }
@@ -532,8 +576,19 @@ static inline phys_addr_t pud_page_paddr(pud_t pud)
 
 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 {
-	WRITE_ONCE(*pgdp, pgd);
-	dsb(ishst);
+	if (in_swapper_pgdir(pgdp)) {
+		pgd_t *fixmap_pgdp;
+
+		spin_lock(&swapper_pgdir_lock);
+		fixmap_pgdp = pgd_set_fixmap(__pa(pgdp));
+		WRITE_ONCE(*fixmap_pgdp, pgd);
+		dsb(ishst);
+		pgd_clear_fixmap();
+		spin_unlock(&swapper_pgdir_lock);
+	} else {
+		WRITE_ONCE(*pgdp, pgd);
+		dsb(ishst);
+	}
 }
 
 static inline void pgd_clear(pgd_t *pgdp)
@@ -586,8 +641,6 @@ static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
 /* to find an entry in a kernel page-table-directory */
 #define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
 
-#define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
-#define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
 
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
@@ -712,13 +765,6 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
 }
 #endif
 
-extern pgd_t init_pg_dir[PTRS_PER_PGD];
-extern pgd_t init_pg_end[];
-extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
-extern pgd_t swapper_pg_end[];
-extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
-extern pgd_t tramp_pg_dir[PTRS_PER_PGD];
-
 /*
  * Encode and decode a swap entry:
  *	bits 0-1:	present (must be zero)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 1d16104aa0b9..7961ed8e6967 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -67,6 +67,8 @@ static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
 static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused;
 static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused;
 
+DEFINE_SPINLOCK(swapper_pgdir_lock);
+
 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 			      unsigned long size, pgprot_t vma_prot)
 {
-- 
2.17.1

[RESEND PATCH v4 6/6] arm64/mm: Move

[Jun Yao]

Move {idmap_pg_dir, tramp_pg_dir, reserved_ttbr0, swapper_pg_dir}
to .rodata section.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
---
 arch/arm64/kernel/vmlinux.lds.S | 39 ++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 2446911f4262..142528a23b44 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -64,8 +64,13 @@ jiffies = jiffies_64;
 	*(.entry.tramp.text)				\
 	. = ALIGN(PAGE_SIZE);				\
 	__entry_tramp_text_end = .;
+
+#define TRAMP_PG_TABLE					\
+	tramp_pg_dir = .;				\
+	. += PAGE_SIZE;
 #else
 #define TRAMP_TEXT
+#define TRAMP_PG_TABLE
 #endif
 
 #define INIT_PG_TABLES					\
@@ -74,6 +79,24 @@ jiffies = jiffies_64;
 	. += SWAPPER_DIR_SIZE;                          \
 	init_pg_end = .;
 
+#ifdef CONFIG_ARM64_SW_TTBR0_PAN
+#define RESERVED_PG_TABLE				\
+	reserved_ttbr0 = .;				\
+	. += RESERVED_TTBR0_SIZE;
+#else
+#define RESERVED_PG_TABLE
+#endif
+
+#define KERNEL_PG_TABLES				\
+	. = ALIGN(PAGE_SIZE);                           \
+	idmap_pg_dir = .;				\
+	. += IDMAP_DIR_SIZE;				\
+	TRAMP_PG_TABLE					\
+	RESERVED_PG_TABLE				\
+	swapper_pg_dir = .;				\
+	. += PAGE_SIZE;					\
+	swapper_pg_end = .;
+
 /*
  * The size of the PE/COFF section that covers the kernel image, which
  * runs from stext to _edata, must be a round multiple of the PE/COFF
@@ -143,6 +166,7 @@ SECTIONS
 	RO_DATA(PAGE_SIZE)		/* everything from this point to     */
 	EXCEPTION_TABLE(8)		/* __init_begin will be marked RO NX */
 	NOTES
+	KERNEL_PG_TABLES
 
 	. = ALIGN(SEGMENT_ALIGN);
 	__init_begin = .;
@@ -224,21 +248,6 @@ SECTIONS
 	BSS_SECTION(0, 0, 0)
 
 	. = ALIGN(PAGE_SIZE);
-	idmap_pg_dir = .;
-	. += IDMAP_DIR_SIZE;
-
-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-	tramp_pg_dir = .;
-	. += PAGE_SIZE;
-#endif
-
-#ifdef CONFIG_ARM64_SW_TTBR0_PAN
-	reserved_ttbr0 = .;
-	. += RESERVED_TTBR0_SIZE;
-#endif
-	swapper_pg_dir = .;
-	. += PAGE_SIZE;
-	swapper_pg_end = .;
 
 	__pecoff_data_size = ABSOLUTE(. - __initdata_begin);
 	_end = .;
-- 
2.17.1