Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

Pull ARM updates from Russell King:

- add support for ELF fdpic binaries on both MMU and noMMU platforms

- linker script cleanups

- support for compressed .data section for XIP images

- discard memblock arrays when possible

- various cleanups

- atomic DMA pool updates

- better diagnostics of missing/corrupt device tree

- export information to allow userspace kexec tool to place images more
inteligently, so that the device tree isn't overwritten by the
booting kernel

- make early_printk more efficient on semihosted systems

- noMMU cleanups

- SA1111 PCMCIA update in preparation for further cleanups

* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (38 commits)
ARM: 8719/1: NOMMU: work around maybe-uninitialized warning
ARM: 8717/2: debug printch/printascii: translate '\n' to "\r\n" not "\n\r"
ARM: 8713/1: NOMMU: Support MPU in XIP configuration
ARM: 8712/1: NOMMU: Use more MPU regions to cover memory
ARM: 8711/1: V7M: Add support for MPU to M-class
ARM: 8710/1: Kconfig: Kill CONFIG_VECTORS_BASE
ARM: 8709/1: NOMMU: Disallow MPU for XIP
ARM: 8708/1: NOMMU: Rework MPU to be mostly done in C
ARM: 8707/1: NOMMU: Update MPU accessors to use cp15 helpers
ARM: 8706/1: NOMMU: Move out MPU setup in separate module
ARM: 8702/1: head-common.S: Clear lr before jumping to start_kernel()
ARM: 8705/1: early_printk: use printascii() rather than printch()
ARM: 8703/1: debug.S: move hexbuf to a writable section
ARM: add additional table to compressed kernel
ARM: decompressor: fix BSS size calculation
pcmcia: sa1111: remove special sa1111 mmio accessors
pcmcia: sa1111: use sa1111_get_irq() to obtain IRQ resources
ARM: better diagnostics with missing/corrupt dtb
ARM: 8699/1: dma-mapping: Remove init_dma_coherent_pool_size()
ARM: 8698/1: dma-mapping: Mark atomic_pool as __ro_after_init
..

arch/arm/Kconfig

···
 	bool
 	default y
 	select ARCH_CLOCKSOURCE_DATA
+	select ARCH_DISCARD_MEMBLOCK if !HAVE_ARCH_PFN_VALID
 	select ARCH_HAS_DEBUG_VIRTUAL
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
 	select ARCH_HAS_ELF_RANDOMIZE
···
 
 config ARCH_MTD_XIP
 	bool
-
-config VECTORS_BASE
-	hex
-	default 0xffff0000 if MMU || CPU_HIGH_VECTOR
-	default DRAM_BASE if REMAP_VECTORS_TO_RAM
-	default 0x00000000
-	help
-	  The base address of exception vectors.  This must be two pages
-	  in size.
 
 config ARM_PATCH_PHYS_VIRT
 	bool "Patch physical to virtual translations at runtime" if EMBEDDED
···
 	  This is the physical address in your flash memory the kernel will
 	  be linked for and stored to.  This address is dependent on your
 	  own flash usage.
+
+config XIP_DEFLATED_DATA
+	bool "Store kernel .data section compressed in ROM"
+	depends on XIP_KERNEL
+	select ZLIB_INFLATE
+	help
+	  Before the kernel is actually executed, its .data section has to be
+	  copied to RAM from ROM. This option allows for storing that data
+	  in compressed form and decompressed to RAM rather than merely being
+	  copied, saving some precious ROM space. A possible drawback is a
+	  slightly longer boot delay.
 
 config KEXEC
 	bool "Kexec system call (EXPERIMENTAL)"

arch/arm/Kconfig-nommu

···
 
 config ARM_MPU
        bool 'Use the ARM v7 PMSA Compliant MPU'
-       depends on CPU_V7
-       default y
+       depends on CPU_V7 || CPU_V7M
+       default y if CPU_V7
        help
          Some ARM systems without an MMU have instead a Memory Protection
          Unit (MPU) that defines the type and permissions for regions of

arch/arm/boot/Makefile

···
 
 ifeq ($(CONFIG_XIP_KERNEL),y)
 
+cmd_deflate_xip_data = $(CONFIG_SHELL) -c \
+	'$(srctree)/$(src)/deflate_xip_data.sh $< $@ || { rm -f $@; false; }'
+
+ifeq ($(CONFIG_XIP_DEFLATED_DATA),y)
+quiet_cmd_mkxip = XIPZ    $@
+cmd_mkxip = $(cmd_objcopy) && $(cmd_deflate_xip_data)
+else
+quiet_cmd_mkxip = $(quiet_cmd_objcopy)
+cmd_mkxip = $(cmd_objcopy)
+endif
+
 $(obj)/xipImage: vmlinux FORCE
-	$(call if_changed,objcopy)
+	$(call if_changed,mkxip)
 	@$(kecho) '  Physical Address of xipImage: $(CONFIG_XIP_PHYS_ADDR)'
 
 $(obj)/Image $(obj)/zImage: FORCE

arch/arm/boot/compressed/Makefile

···
 asflags-y := -DZIMAGE
 
 # Supply kernel BSS size to the decompressor via a linker symbol.
-KBSS_SZ = $(shell $(CROSS_COMPILE)size $(obj)/../../../../vmlinux | \
-		awk 'END{print $$3}')
+KBSS_SZ = $(shell $(CROSS_COMPILE)nm $(obj)/../../../../vmlinux | \
+		perl -e 'while (<>) { \
+			$$bss_start=hex($$1) if /^([[:xdigit:]]+) B __bss_start$$/; \
+			$$bss_end=hex($$1) if /^([[:xdigit:]]+) B __bss_stop$$/; \
+		}; printf "%d\n", $$bss_end - $$bss_start;')
 LDFLAGS_vmlinux = --defsym _kernel_bss_size=$(KBSS_SZ)
 # Supply ZRELADDR to the decompressor via a linker symbol.
 ifneq ($(CONFIG_AUTO_ZRELADDR),y)

arch/arm/boot/compressed/head.S

···
 		.word	_magic_start	@ absolute load/run zImage address
 		.word	_magic_end	@ zImage end address
 		.word	0x04030201	@ endianness flag
+		.word	0x45454545	@ another magic number to indicate
+		.word	_magic_table	@ additional data table
 
 		__EFI_HEADER
 1:

arch/arm/boot/compressed/vmlinux.lds.S

···
     *(.glue_7t)
     *(.glue_7)
   }
+  .table : ALIGN(4) {
+    _table_start = .;
+    LONG(ZIMAGE_MAGIC(2))
+    LONG(ZIMAGE_MAGIC(0x5a534c4b))
+    LONG(ZIMAGE_MAGIC(__piggy_size_addr - _start))
+    LONG(ZIMAGE_MAGIC(_kernel_bss_size))
+    LONG(0)
+    _table_end = .;
+  }
   .rodata : {
     *(.rodata)
     *(.rodata.*)
   }
   .piggydata : {
     *(.piggydata)
+    __piggy_size_addr = . - 4;
   }
 
   . = ALIGN(4);
···
   _magic_sig = ZIMAGE_MAGIC(0x016f2818);
   _magic_start = ZIMAGE_MAGIC(_start);
   _magic_end = ZIMAGE_MAGIC(_edata);
+  _magic_table = ZIMAGE_MAGIC(_table_start - _start);
 
   . = BSS_START;
   __bss_start = .;

arch/arm/boot/deflate_xip_data.sh

···
+#!/bin/sh
+
+# XIP kernel .data segment compressor
+#
+# Created by:	Nicolas Pitre, August 2017
+# Copyright:	(C) 2017  Linaro Limited
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+
+# This script locates the start of the .data section in xipImage and
+# substitutes it with a compressed version. The needed offsets are obtained
+# from symbol addresses in vmlinux. It is expected that .data extends to
+# the end of xipImage.
+
+set -e
+
+VMLINUX="$1"
+XIPIMAGE="$2"
+
+DD="dd status=none"
+
+# Use "make V=1" to debug this script.
+case "$KBUILD_VERBOSE" in
+*1*)
+	set -x
+	;;
+esac
+
+sym_val() {
+	# extract hex value for symbol in $1
+	local val=$($NM "$VMLINUX" | sed -n "/ $1$/{s/ .*$//p;q}")
+	[ "$val" ] || { echo "can't find $1 in $VMLINUX" 1>&2; exit 1; }
+	# convert from hex to decimal
+	echo $((0x$val))
+}
+
+__data_loc=$(sym_val __data_loc)
+_edata_loc=$(sym_val _edata_loc)
+base_offset=$(sym_val _xiprom)
+
+# convert to file based offsets
+data_start=$(($__data_loc - $base_offset))
+data_end=$(($_edata_loc - $base_offset))
+
+# Make sure data occupies the last part of the file.
+file_end=$(stat -c "%s" "$XIPIMAGE")
+if [ "$file_end" != "$data_end" ]; then
+	printf "end of xipImage doesn't match with _edata_loc (%#x vs %#x)\n" \
+	       $(($file_end + $base_offset)) $_edata_loc 2>&1
+	exit 1;
+fi
+
+# be ready to clean up
+trap 'rm -f "$XIPIMAGE.tmp"' 0 1 2 3
+
+# substitute the data section by a compressed version
+$DD if="$XIPIMAGE" count=$data_start iflag=count_bytes of="$XIPIMAGE.tmp"
+$DD if="$XIPIMAGE"  skip=$data_start iflag=skip_bytes |
+gzip -9 >> "$XIPIMAGE.tmp"
+
+# replace kernel binary
+mv -f "$XIPIMAGE.tmp" "$XIPIMAGE"

arch/arm/include/asm/cputype.h

···
 	return read_cpuid(CPUID_CACHETYPE);
 }
 
+static inline unsigned int __attribute_const__ read_cpuid_mputype(void)
+{
+	return read_cpuid(CPUID_MPUIR);
+}
+
 #elif defined(CONFIG_CPU_V7M)
 
 static inline unsigned int __attribute_const__ read_cpuid_id(void)
···
 static inline unsigned int __attribute_const__ read_cpuid_cachetype(void)
 {
 	return readl(BASEADDR_V7M_SCB + V7M_SCB_CTR);
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_mputype(void)
+{
+	return readl(BASEADDR_V7M_SCB + MPU_TYPE);
 }
 
 #else /* ifdef CONFIG_CPU_CP15 / elif defined(CONFIG_CPU_V7M) */

arch/arm/include/asm/dma-mapping.h

···
 			unsigned long attrs);
 
 /*
- * This can be called during early boot to increase the size of the atomic
- * coherent DMA pool above the default value of 256KiB. It must be called
- * before postcore_initcall.
- */
-extern void __init init_dma_coherent_pool_size(unsigned long size);
-
-/*
  * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
  * and utilize bounce buffers as needed to work around limited DMA windows.
  *

arch/arm/include/asm/elf.h

···
 extern int elf_check_arch(const struct elf32_hdr *);
 #define elf_check_arch elf_check_arch
 
+#define ELFOSABI_ARM_FDPIC  65	/* ARM FDPIC platform */
+#define elf_check_fdpic(x)  ((x)->e_ident[EI_OSABI] == ELFOSABI_ARM_FDPIC)
+#define elf_check_const_displacement(x)  ((x)->e_flags & EF_ARM_PIC)
+#define ELF_FDPIC_CORE_EFLAGS  0
+
 #define vmcore_elf64_check_arch(x) (0)
 
-extern int arm_elf_read_implies_exec(const struct elf32_hdr *, int);
-#define elf_read_implies_exec(ex,stk) arm_elf_read_implies_exec(&(ex), stk)
+extern int arm_elf_read_implies_exec(int);
+#define elf_read_implies_exec(ex,stk) arm_elf_read_implies_exec(stk)
 
 struct task_struct;
 int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs);
···
    registered with atexit, as per the SVR4 ABI.  A value of 0 means we 
    have no such handler.  */
 #define ELF_PLAT_INIT(_r, load_addr)	(_r)->ARM_r0 = 0
+
+#define ELF_FDPIC_PLAT_INIT(_r, _exec_map_addr, _interp_map_addr, dynamic_addr) \
+	do { \
+		(_r)->ARM_r7 = _exec_map_addr; \
+		(_r)->ARM_r8 = _interp_map_addr; \
+		(_r)->ARM_r9 = dynamic_addr; \
+	} while(0)
 
 extern void elf_set_personality(const struct elf32_hdr *);
 #define SET_PERSONALITY(ex)	elf_set_personality(&(ex))

arch/arm/include/asm/highmem.h

···
 	} while (0)
 
 extern pte_t *pkmap_page_table;
-extern pte_t *fixmap_page_table;
 
 extern void *kmap_high(struct page *page);
 extern void kunmap_high(struct page *page);

arch/arm/include/asm/mmu.h

···
 #ifdef CONFIG_VDSO
 	unsigned long	vdso;
 #endif
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	unsigned long	exec_fdpic_loadmap;
+	unsigned long	interp_fdpic_loadmap;
+#endif
 } mm_context_t;
 
 #ifdef CONFIG_CPU_HAS_ASID
···
  */
 typedef struct {
 	unsigned long	end_brk;
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	unsigned long	exec_fdpic_loadmap;
+	unsigned long	interp_fdpic_loadmap;
+#endif
 } mm_context_t;
 
 #endif

arch/arm/include/asm/mpu.h

···
 #ifndef __ARM_MPU_H
 #define __ARM_MPU_H
 
-#ifdef CONFIG_ARM_MPU
-
 /* MPUIR layout */
 #define MPUIR_nU		1
 #define MPUIR_DREGION		8
···
 /* MPU D/I Size Register fields */
 #define MPU_RSR_SZ		1
 #define MPU_RSR_EN		0
+#define MPU_RSR_SD		8
+
+/* Number of subregions (SD) */
+#define MPU_NR_SUBREGS		8
+#define MPU_MIN_SUBREG_SIZE	256
 
 /* The D/I RSR value for an enabled region spanning the whole of memory */
 #define MPU_RSR_ALL_MEM		63
···
 #endif
 
 /* Access permission bits of ACR (only define those that we use)*/
+#define MPU_AP_PL1RO_PL0NA	(0x5 << 8)
 #define MPU_AP_PL1RW_PL0RW	(0x3 << 8)
 #define MPU_AP_PL1RW_PL0R0	(0x2 << 8)
 #define MPU_AP_PL1RW_PL0NA	(0x1 << 8)
···
 #define MPU_PROBE_REGION	0
 #define MPU_BG_REGION		1
 #define MPU_RAM_REGION		2
-#define MPU_VECTORS_REGION	3
+#define MPU_ROM_REGION		3
 
 /* Maximum number of regions Linux is interested in */
 #define MPU_MAX_REGIONS		16
···
 };
 
 struct mpu_rgn_info {
-	u32 mpuir;
+	unsigned int used;
 	struct mpu_rgn rgns[MPU_MAX_REGIONS];
 };
 extern struct mpu_rgn_info mpu_rgn_info;
 
-#endif /* __ASSEMBLY__ */
+#ifdef CONFIG_ARM_MPU
 
-#endif /* CONFIG_ARM_MPU */
+extern void __init adjust_lowmem_bounds_mpu(void);
+extern void __init mpu_setup(void);
+
+#else
+
+static inline void adjust_lowmem_bounds_mpu(void) {}
+static inline void mpu_setup(void) {}
+
+#endif /* !CONFIG_ARM_MPU */
+
+#endif /* __ASSEMBLY__ */
 
 #endif

arch/arm/include/asm/processor.h

···
 
 #define INIT_THREAD  {	}
 
-#ifdef CONFIG_MMU
-#define nommu_start_thread(regs) do { } while (0)
-#else
-#define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
-#endif
-
 #define start_thread(regs,pc,sp)					\
 ({									\
+	unsigned long r7, r8, r9;					\
+									\
+	if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC)) {			\
+		r7 = regs->ARM_r7;					\
+		r8 = regs->ARM_r8;					\
+		r9 = regs->ARM_r9;					\
+	}								\
 	memset(regs->uregs, 0, sizeof(regs->uregs));			\
+	if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&			\
+	    current->personality & FDPIC_FUNCPTRS) {			\
+		regs->ARM_r7 = r7;					\
+		regs->ARM_r8 = r8;					\
+		regs->ARM_r9 = r9;					\
+		regs->ARM_r10 = current->mm->start_data;		\
+	} else if (!IS_ENABLED(CONFIG_MMU))				\
+		regs->ARM_r10 = current->mm->start_data;		\
 	if (current->personality & ADDR_LIMIT_32BIT)			\
 		regs->ARM_cpsr = USR_MODE;				\
 	else								\
···
 	regs->ARM_cpsr |= PSR_ENDSTATE;					\
 	regs->ARM_pc = pc & ~1;		/* pc */			\
 	regs->ARM_sp = sp;		/* sp */			\
-	nommu_start_thread(regs);					\
 })
 
 /* Forward declaration, a strange C thing */

arch/arm/include/asm/smp.h

···
  */
 struct secondary_data {
 	union {
-		unsigned long mpu_rgn_szr;
+		struct mpu_rgn_info *mpu_rgn_info;
 		u64 pgdir;
 	};
 	unsigned long swapper_pg_dir;

arch/arm/include/asm/ucontext.h

···
 #define _ASMARM_UCONTEXT_H
 
 #include <asm/fpstate.h>
+#include <asm/user.h>
 
 /*
  * struct sigcontext only has room for the basic registers, but struct

arch/arm/include/asm/v7m.h

···
 #define	V7M_SCB_CCSIDR		0x80	/* Cache size ID register */
 #define	V7M_SCB_CSSELR		0x84	/* Cache size selection register */
 
+/* Memory-mapped MPU registers for M-class */
+#define MPU_TYPE		0x90
+#define MPU_CTRL		0x94
+#define MPU_CTRL_ENABLE		1
+#define MPU_CTRL_PRIVDEFENA	(1 << 2)
+
+#define MPU_RNR			0x98
+#define MPU_RBAR		0x9c
+#define MPU_RASR		0xa0
+
 /* Cache opeartions */
 #define	V7M_SCB_ICIALLU		0x250	/* I-cache invalidate all to PoU */
 #define	V7M_SCB_ICIMVAU		0x258	/* I-cache invalidate by MVA to PoU */

arch/arm/include/uapi/asm/ptrace.h

···
 #define PTRACE_SETVFPREGS	28
 #define PTRACE_GETHBPREGS	29
 #define PTRACE_SETHBPREGS	30
+#define PTRACE_GETFDPIC		31
+
+#define PTRACE_GETFDPIC_EXEC	0
+#define PTRACE_GETFDPIC_INTERP	1
 
 /*
  * PSR bits

arch/arm/include/uapi/asm/unistd.h

···
 #define __ARM_NR_usr26			(__ARM_NR_BASE+3)
 #define __ARM_NR_usr32			(__ARM_NR_BASE+4)
 #define __ARM_NR_set_tls		(__ARM_NR_BASE+5)
+#define __ARM_NR_get_tls		(__ARM_NR_BASE+6)
 
 #endif /* _UAPI__ASM_ARM_UNISTD_H */

arch/arm/kernel/Makefile

···
 obj-$(CONFIG_DEBUG_LL)	+= debug.o
 obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 
+# This is executed very early using a temporary stack when no memory allocator
+# nor global data is available. Everything has to be allocated on the stack.
+CFLAGS_head-inflate-data.o := $(call cc-option,-Wframe-larger-than=10240)
+obj-$(CONFIG_XIP_DEFLATED_DATA) += head-inflate-data.o
+
 obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
 AFLAGS_hyp-stub.o		:=-Wa,-march=armv7-a
 ifeq ($(CONFIG_ARM_PSCI),y)

arch/arm/kernel/asm-offsets.c

···
 #include <asm/mach/arch.h>
 #include <asm/thread_info.h>
 #include <asm/memory.h>
+#include <asm/mpu.h>
 #include <asm/procinfo.h>
 #include <asm/suspend.h>
 #include <asm/vdso_datapage.h>
 #include <asm/hardware/cache-l2x0.h>
 #include <linux/kbuild.h>
+#include "signal.h"
 
 /*
  * Make sure that the compiler and target are compatible.
···
   DEFINE(SVC_ADDR_LIMIT,	offsetof(struct svc_pt_regs, addr_limit));
   DEFINE(SVC_REGS_SIZE,		sizeof(struct svc_pt_regs));
   BLANK();
+  DEFINE(SIGFRAME_RC3_OFFSET,	offsetof(struct sigframe, retcode[3]));
+  DEFINE(RT_SIGFRAME_RC3_OFFSET, offsetof(struct rt_sigframe, sig.retcode[3]));
+  BLANK();
 #ifdef CONFIG_CACHE_L2X0
   DEFINE(L2X0_R_PHY_BASE,	offsetof(struct l2x0_regs, phy_base));
   DEFINE(L2X0_R_AUX_CTRL,	offsetof(struct l2x0_regs, aux_ctrl));
···
   BLANK();
 #ifdef CONFIG_VDSO
   DEFINE(VDSO_DATA_SIZE,	sizeof(union vdso_data_store));
+#endif
+  BLANK();
+#ifdef CONFIG_ARM_MPU
+  DEFINE(MPU_RNG_INFO_RNGS,	offsetof(struct mpu_rgn_info, rgns));
+  DEFINE(MPU_RNG_INFO_USED,	offsetof(struct mpu_rgn_info, used));
+
+  DEFINE(MPU_RNG_SIZE,		sizeof(struct mpu_rgn));
+  DEFINE(MPU_RGN_DRBAR,		offsetof(struct mpu_rgn, drbar));
+  DEFINE(MPU_RGN_DRSR,		offsetof(struct mpu_rgn, drsr));
+  DEFINE(MPU_RGN_DRACR,		offsetof(struct mpu_rgn, dracr));
 #endif
   return 0; 
 }

arch/arm/kernel/atags_parse.c

···
 			break;
 		}
 
-	if (!mdesc) {
-		early_print("\nError: unrecognized/unsupported machine ID"
-			    " (r1 = 0x%08x).\n\n", machine_nr);
-		dump_machine_table(); /* does not return */
-	}
+	if (!mdesc)
+		return NULL;
 
 	if (__atags_pointer)
 		tags = phys_to_virt(__atags_pointer);

arch/arm/kernel/debug.S

···
 
 ENTRY(printhex2)
 		mov	r1, #2
-printhex:	adr	r2, hexbuf
+printhex:	adr	r2, hexbuf_rel
+		ldr	r3, [r2]
+		add	r2, r2, r3
 		add	r3, r2, r1
 		mov	r1, #0
 		strb	r1, [r3]
···
 		b	printascii
 ENDPROC(printhex2)
 
-hexbuf:		.space 16
+		.pushsection .bss
+hexbuf_addr:	.space 16
+		.popsection
+		.align
+hexbuf_rel:	.long	hexbuf_addr - .
 
 		.ltorg
 
···
 
 ENTRY(printascii)
 		addruart_current r3, r1, r2
-		b	2f
-1:		waituart r2, r3
-		senduart r1, r3
-		busyuart r2, r3
-		teq	r1, #'\n'
-		moveq	r1, #'\r'
-		beq	1b
-2:		teq	r0, #0
+1:		teq	r0, #0
 		ldrneb	r1, [r0], #1
 		teqne	r1, #0
-		bne	1b
-		ret	lr
+		reteq	lr
+2:		teq     r1, #'\n'
+		bne	3f
+		mov	r1, #'\r'
+		waituart r2, r3
+		senduart r1, r3
+		busyuart r2, r3
+		mov	r1, #'\n'
+3:		waituart r2, r3
+		senduart r1, r3
+		busyuart r2, r3
+		b	1b
 ENDPROC(printascii)
 
 ENTRY(printch)
 		addruart_current r3, r1, r2
 		mov	r1, r0
 		mov	r0, #0
-		b	1b
+		b	2b
 ENDPROC(printch)
 
 #ifdef CONFIG_MMU
···
 ENDPROC(printascii)
 
 ENTRY(printch)
-		adr	r1, hexbuf
+		adr	r1, hexbuf_rel
+		ldr	r2, [r1]
+		add	r1, r1, r2
 		strb	r0, [r1]
 		mov	r0, #0x03		@ SYS_WRITEC
 	ARM(	svc	#0x123456	)

arch/arm/kernel/early_printk.c

···
 #include <linux/kernel.h>
 #include <linux/console.h>
 #include <linux/init.h>
+#include <linux/string.h>
 
-extern void printch(int);
+extern void printascii(const char *);
 
 static void early_write(const char *s, unsigned n)
 {
-	while (n-- > 0) {
-		if (*s == '\n')
-			printch('\r');
-		printch(*s);
-		s++;
+	char buf[128];
+	while (n) {
+		unsigned l = min(n, sizeof(buf)-1);
+		memcpy(buf, s, l);
+		buf[l] = 0;
+		s += l;
+		n -= l;
+		printascii(buf);
 	}
 }
 

arch/arm/kernel/elf.c

···
 #include <linux/personality.h>
 #include <linux/binfmts.h>
 #include <linux/elf.h>
+#include <linux/elf-fdpic.h>
 #include <asm/system_info.h>
 
 int elf_check_arch(const struct elf32_hdr *x)
···
  *  - the binary requires an executable stack
  *  - we're running on a CPU which doesn't support NX.
  */
-int arm_elf_read_implies_exec(const struct elf32_hdr *x, int executable_stack)
+int arm_elf_read_implies_exec(int executable_stack)
 {
 	if (executable_stack != EXSTACK_DISABLE_X)
 		return 1;
···
 	return 0;
 }
 EXPORT_SYMBOL(arm_elf_read_implies_exec);
+
+#if defined(CONFIG_MMU) && defined(CONFIG_BINFMT_ELF_FDPIC)
+
+void elf_fdpic_arch_lay_out_mm(struct elf_fdpic_params *exec_params,
+			       struct elf_fdpic_params *interp_params,
+			       unsigned long *start_stack,
+			       unsigned long *start_brk)
+{
+	elf_set_personality(&exec_params->hdr);
+
+	exec_params->load_addr = 0x8000;
+	interp_params->load_addr = ELF_ET_DYN_BASE;
+	*start_stack = TASK_SIZE - SZ_16M;
+
+	if ((exec_params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) == ELF_FDPIC_FLAG_INDEPENDENT) {
+		exec_params->flags &= ~ELF_FDPIC_FLAG_ARRANGEMENT;
+		exec_params->flags |= ELF_FDPIC_FLAG_CONSTDISP;
+	}
+}
+
+#endif

arch/arm/kernel/entry-common.S

···
  * offset, we return EINVAL.
  */
 sys_mmap2:
-#if PAGE_SHIFT > 12
-		tst	r5, #PGOFF_MASK
-		moveq	r5, r5, lsr #PAGE_SHIFT - 12
-		streq	r5, [sp, #4]
-		beq	sys_mmap_pgoff
-		mov	r0, #-EINVAL
-		ret	lr
-#else
 		str	r5, [sp, #4]
 		b	sys_mmap_pgoff
-#endif
 ENDPROC(sys_mmap2)
 
 #ifdef CONFIG_OABI_COMPAT

arch/arm/kernel/head-common.S

···
  */
 	__INIT
 __mmap_switched:
-	adr	r3, __mmap_switched_data
 
-	ldmia	r3!, {r4, r5, r6, r7}
-	cmp	r4, r5				@ Copy data segment if needed
-1:	cmpne	r5, r6
-	ldrne	fp, [r4], #4
-	strne	fp, [r5], #4
-	bne	1b
+	mov	r7, r1
+	mov	r8, r2
+	mov	r10, r0
 
-	mov	fp, #0				@ Clear BSS (and zero fp)
-1:	cmp	r6, r7
-	strcc	fp, [r6],#4
-	bcc	1b
+	adr	r4, __mmap_switched_data
+	mov	fp, #0
 
- ARM(	ldmia	r3, {r4, r5, r6, r7, sp})
- THUMB(	ldmia	r3, {r4, r5, r6, r7}	)
- THUMB(	ldr	sp, [r3, #16]		)
-	str	r9, [r4]			@ Save processor ID
-	str	r1, [r5]			@ Save machine type
-	str	r2, [r6]			@ Save atags pointer
-	cmp	r7, #0
-	strne	r0, [r7]			@ Save control register values
+#if defined(CONFIG_XIP_DEFLATED_DATA)
+   ARM(	ldr	sp, [r4], #4 )
+ THUMB(	ldr	sp, [r4] )
+ THUMB(	add	r4, #4 )
+	bl	__inflate_kernel_data		@ decompress .data to RAM
+	teq	r0, #0
+	bne	__error
+#elif defined(CONFIG_XIP_KERNEL)
+   ARM(	ldmia	r4!, {r0, r1, r2, sp} )
+ THUMB(	ldmia	r4!, {r0, r1, r2, r3} )
+ THUMB(	mov	sp, r3 )
+	sub	r2, r2, r1
+	bl	memcpy				@ copy .data to RAM
+#endif
+
+   ARM(	ldmia	r4!, {r0, r1, sp} )
+ THUMB(	ldmia	r4!, {r0, r1, r3} )
+ THUMB(	mov	sp, r3 )
+	sub	r1, r1, r0
+	bl	__memzero			@ clear .bss
+
+	ldmia	r4, {r0, r1, r2, r3}
+	str	r9, [r0]			@ Save processor ID
+	str	r7, [r1]			@ Save machine type
+	str	r8, [r2]			@ Save atags pointer
+	cmp	r3, #0
+	strne	r10, [r3]			@ Save control register values
+	mov	lr, #0
 	b	start_kernel
 ENDPROC(__mmap_switched)
 
 	.align	2
 	.type	__mmap_switched_data, %object
 __mmap_switched_data:
-	.long	__data_loc			@ r4
-	.long	_sdata				@ r5
-	.long	__bss_start			@ r6
-	.long	_end				@ r7
-	.long	processor_id			@ r4
-	.long	__machine_arch_type		@ r5
-	.long	__atags_pointer			@ r6
-#ifdef CONFIG_CPU_CP15
-	.long	cr_alignment			@ r7
-#else
-	.long	0				@ r7
+#ifdef CONFIG_XIP_KERNEL
+#ifndef CONFIG_XIP_DEFLATED_DATA
+	.long	_sdata				@ r0
+	.long	__data_loc			@ r1
+	.long	_edata_loc			@ r2
 #endif
+	.long	__bss_stop			@ sp (temporary stack in .bss)
+#endif
+
+	.long	__bss_start			@ r0
+	.long	__bss_stop			@ r1
 	.long	init_thread_union + THREAD_START_SP @ sp
+
+	.long	processor_id			@ r0
+	.long	__machine_arch_type		@ r1
+	.long	__atags_pointer			@ r2
+#ifdef CONFIG_CPU_CP15
+	.long	cr_alignment			@ r3
+#else
+	.long	0				@ r3
+#endif
 	.size	__mmap_switched_data, . - __mmap_switched_data
 
 /*

arch/arm/kernel/head-inflate-data.c

···
+/*
+ * XIP kernel .data segment decompressor
+ *
+ * Created by:	Nicolas Pitre, August 2017
+ * Copyright:	(C) 2017  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/zutil.h>
+
+/* for struct inflate_state */
+#include "../../../lib/zlib_inflate/inftrees.h"
+#include "../../../lib/zlib_inflate/inflate.h"
+#include "../../../lib/zlib_inflate/infutil.h"
+
+extern char __data_loc[];
+extern char _edata_loc[];
+extern char _sdata[];
+
+/*
+ * This code is called very early during the boot process to decompress
+ * the .data segment stored compressed in ROM. Therefore none of the global
+ * variables are valid yet, hence no kernel services such as memory
+ * allocation is available. Everything must be allocated on the stack and
+ * we must avoid any global data access. We use a temporary stack located
+ * in the .bss area. The linker script makes sure the .bss is big enough
+ * to hold our stack frame plus some room for called functions.
+ *
+ * We mimic the code in lib/decompress_inflate.c to use the smallest work
+ * area possible. And because everything is statically allocated on the
+ * stack then there is no need to clean up before returning.
+ */
+
+int __init __inflate_kernel_data(void)
+{
+	struct z_stream_s stream, *strm = &stream;
+	struct inflate_state state;
+	char *in = __data_loc;
+	int rc;
+
+	/* Check and skip gzip header (assume no filename) */
+	if (in[0] != 0x1f || in[1] != 0x8b || in[2] != 0x08 || in[3] & ~3)
+		return -1;
+	in += 10;
+
+	strm->workspace = &state;
+	strm->next_in = in;
+	strm->avail_in = _edata_loc - __data_loc;  /* upper bound */
+	strm->next_out = _sdata;
+	strm->avail_out = _edata_loc - __data_loc;
+	zlib_inflateInit2(strm, -MAX_WBITS);
+	WS(strm)->inflate_state.wsize = 0;
+	WS(strm)->inflate_state.window = NULL;
+	rc = zlib_inflate(strm, Z_FINISH);
+	if (rc == Z_OK || rc == Z_STREAM_END)
+		rc = strm->avail_out;  /* should be 0 */
+	return rc;
+}

arch/arm/kernel/head-nommu.S

···
  */
 #include <linux/linkage.h>
 #include <linux/init.h>
+#include <linux/errno.h>
 
 #include <asm/assembler.h>
 #include <asm/ptrace.h>
···
 
 #ifdef CONFIG_ARM_MPU
 	/* Use MPU region info supplied by __cpu_up */
-	ldr	r6, [r7]			@ get secondary_data.mpu_szr
-	bl      __setup_mpu			@ Initialize the MPU
+	ldr	r6, [r7]			@ get secondary_data.mpu_rgn_info
+	bl      __secondary_setup_mpu		@ Initialize the MPU
 #endif
 
 	badr	lr, 1f				@ return (PIC) address
···
 #ifdef CONFIG_ARM_MPU
 
 
+#ifndef CONFIG_CPU_V7M
 /* Set which MPU region should be programmed */
-.macro set_region_nr tmp, rgnr
+.macro set_region_nr tmp, rgnr, unused
 	mov	\tmp, \rgnr			@ Use static region numbers
 	mcr	p15, 0, \tmp, c6, c2, 0		@ Write RGNR
 .endm
 
 /* Setup a single MPU region, either D or I side (D-side for unified) */
-.macro setup_region bar, acr, sr, side = MPU_DATA_SIDE
+.macro setup_region bar, acr, sr, side = MPU_DATA_SIDE, unused
 	mcr	p15, 0, \bar, c6, c1, (0 + \side)	@ I/DRBAR
 	mcr	p15, 0, \acr, c6, c1, (4 + \side)	@ I/DRACR
 	mcr	p15, 0, \sr, c6, c1, (2 + \side)		@ I/DRSR
 .endm
+#else
+.macro set_region_nr tmp, rgnr, base
+	mov	\tmp, \rgnr
+	str     \tmp, [\base, #MPU_RNR]
+.endm
 
+.macro setup_region bar, acr, sr, unused, base
+	lsl     \acr, \acr, #16
+	orr     \acr, \acr, \sr
+	str     \bar, [\base, #MPU_RBAR]
+	str     \acr, [\base, #MPU_RASR]
+.endm
+
+#endif
 /*
  * Setup the MPU and initial MPU Regions. We create the following regions:
  * Region 0: Use this for probing the MPU details, so leave disabled.
···
 ENTRY(__setup_mpu)
 
 	/* Probe for v7 PMSA compliance */
-	mrc	p15, 0, r0, c0, c1, 4		@ Read ID_MMFR0
+M_CLASS(movw	r12, #:lower16:BASEADDR_V7M_SCB)
+M_CLASS(movt	r12, #:upper16:BASEADDR_V7M_SCB)
+
+AR_CLASS(mrc	p15, 0, r0, c0, c1, 4)		@ Read ID_MMFR0
+M_CLASS(ldr	r0, [r12, 0x50])
 	and	r0, r0, #(MMFR0_PMSA)		@ PMSA field
 	teq	r0, #(MMFR0_PMSAv7)		@ PMSA v7
-	bne	__error_p			@ Fail: ARM_MPU on NOT v7 PMSA
+	bxne	lr
 
 	/* Determine whether the D/I-side memory map is unified. We set the
 	 * flags here and continue to use them for the rest of this function */
-	mrc	p15, 0, r0, c0, c0, 4		@ MPUIR
+AR_CLASS(mrc	p15, 0, r0, c0, c0, 4)		@ MPUIR
+M_CLASS(ldr    r0, [r12, #MPU_TYPE])
 	ands	r5, r0, #MPUIR_DREGION_SZMASK	@ 0 size d region => No MPU
-	beq	__error_p			@ Fail: ARM_MPU and no MPU
+	bxeq	lr
 	tst	r0, #MPUIR_nU			@ MPUIR_nU = 0 for unified
 
 	/* Setup second region first to free up r6 */
-	set_region_nr r0, #MPU_RAM_REGION
+	set_region_nr r0, #MPU_RAM_REGION, r12
 	isb
 	/* Full access from PL0, PL1, shared for CONFIG_SMP, cacheable */
 	ldr	r0, =PLAT_PHYS_OFFSET		@ RAM starts at PHYS_OFFSET
 	ldr	r5,=(MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL)
 
-	setup_region r0, r5, r6, MPU_DATA_SIDE	@ PHYS_OFFSET, shared, enabled
-	beq	1f				@ Memory-map not unified
-	setup_region r0, r5, r6, MPU_INSTR_SIDE @ PHYS_OFFSET, shared, enabled
+	setup_region r0, r5, r6, MPU_DATA_SIDE, r12	@ PHYS_OFFSET, shared, enabled
+	beq	1f					@ Memory-map not unified
+	setup_region r0, r5, r6, MPU_INSTR_SIDE, r12	@ PHYS_OFFSET, shared, enabled
 1:	isb
 
 	/* First/background region */
-	set_region_nr r0, #MPU_BG_REGION
+	set_region_nr r0, #MPU_BG_REGION, r12
 	isb
 	/* Execute Never,  strongly ordered, inaccessible to PL0, rw PL1  */
 	mov	r0, #0				@ BG region starts at 0x0
 	ldr	r5,=(MPU_ACR_XN | MPU_RGN_STRONGLY_ORDERED | MPU_AP_PL1RW_PL0NA)
 	mov	r6, #MPU_RSR_ALL_MEM		@ 4GB region, enabled
 
-	setup_region r0, r5, r6, MPU_DATA_SIDE	@ 0x0, BG region, enabled
-	beq	2f				@ Memory-map not unified
-	setup_region r0, r5, r6, MPU_INSTR_SIDE @ 0x0, BG region, enabled
+	setup_region r0, r5, r6, MPU_DATA_SIDE, r12	@ 0x0, BG region, enabled
+	beq	2f					@ Memory-map not unified
+	setup_region r0, r5, r6, MPU_INSTR_SIDE r12	@ 0x0, BG region, enabled
 2:	isb
 
-	/* Vectors region */
-	set_region_nr r0, #MPU_VECTORS_REGION
+#ifdef CONFIG_XIP_KERNEL
+	set_region_nr r0, #MPU_ROM_REGION, r12
 	isb
-	/* Shared, inaccessible to PL0, rw PL1 */
-	mov	r0, #CONFIG_VECTORS_BASE	@ Cover from VECTORS_BASE
-	ldr	r5,=(MPU_AP_PL1RW_PL0NA | MPU_RGN_NORMAL)
-	/* Writing N to bits 5:1 (RSR_SZ) --> region size 2^N+1 */
-	mov	r6, #(((2 * PAGE_SHIFT - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN)
 
-	setup_region r0, r5, r6, MPU_DATA_SIDE	@ VECTORS_BASE, PL0 NA, enabled
-	beq	3f				@ Memory-map not unified
-	setup_region r0, r5, r6, MPU_INSTR_SIDE	@ VECTORS_BASE, PL0 NA, enabled
+	ldr	r5,=(MPU_AP_PL1RO_PL0NA | MPU_RGN_NORMAL)
+
+	ldr	r0, =CONFIG_XIP_PHYS_ADDR		@ ROM start
+	ldr     r6, =(_exiprom)				@ ROM end
+	sub	r6, r6, r0				@ Minimum size of region to map
+	clz	r6, r6					@ Region size must be 2^N...
+	rsb	r6, r6, #31				@ ...so round up region size
+	lsl	r6, r6, #MPU_RSR_SZ			@ Put size in right field
+	orr	r6, r6, #(1 << MPU_RSR_EN)		@ Set region enabled bit
+
+	setup_region r0, r5, r6, MPU_DATA_SIDE, r12	@ XIP_PHYS_ADDR, shared, enabled
+	beq	3f					@ Memory-map not unified
+	setup_region r0, r5, r6, MPU_INSTR_SIDE, r12	@ XIP_PHYS_ADDR, shared, enabled
 3:	isb
+#endif
+
+	/* Enable the MPU */
+AR_CLASS(mrc	p15, 0, r0, c1, c0, 0)		@ Read SCTLR
+AR_CLASS(bic	r0, r0, #CR_BR)			@ Disable the 'default mem-map'
+AR_CLASS(orr	r0, r0, #CR_M)			@ Set SCTRL.M (MPU on)
+AR_CLASS(mcr	p15, 0, r0, c1, c0, 0)		@ Enable MPU
+
+M_CLASS(ldr	r0, [r12, #MPU_CTRL])
+M_CLASS(bic	r0, #MPU_CTRL_PRIVDEFENA)
+M_CLASS(orr	r0, #MPU_CTRL_ENABLE)
+M_CLASS(str	r0, [r12, #MPU_CTRL])
+	isb
+
+	ret	lr
+ENDPROC(__setup_mpu)
+
+#ifdef CONFIG_SMP
+/*
+ * r6: pointer at mpu_rgn_info
+ */
+
+ENTRY(__secondary_setup_mpu)
+	/* Probe for v7 PMSA compliance */
+	mrc	p15, 0, r0, c0, c1, 4		@ Read ID_MMFR0
+	and	r0, r0, #(MMFR0_PMSA)		@ PMSA field
+	teq	r0, #(MMFR0_PMSAv7)		@ PMSA v7
+	bne	__error_p
+
+	/* Determine whether the D/I-side memory map is unified. We set the
+	 * flags here and continue to use them for the rest of this function */
+	mrc	p15, 0, r0, c0, c0, 4		@ MPUIR
+	ands	r5, r0, #MPUIR_DREGION_SZMASK	@ 0 size d region => No MPU
+	beq	__error_p
+
+	ldr	r4, [r6, #MPU_RNG_INFO_USED]
+	mov	r5, #MPU_RNG_SIZE
+	add	r3, r6, #MPU_RNG_INFO_RNGS
+	mla	r3, r4, r5, r3
+
+1:
+	tst	r0, #MPUIR_nU			@ MPUIR_nU = 0 for unified
+	sub	r3, r3, #MPU_RNG_SIZE
+	sub	r4, r4, #1
+
+	set_region_nr r0, r4
+	isb
+
+	ldr	r0, [r3, #MPU_RGN_DRBAR]
+	ldr	r6, [r3, #MPU_RGN_DRSR]
+	ldr	r5, [r3, #MPU_RGN_DRACR]
+
+	setup_region r0, r5, r6, MPU_DATA_SIDE
+	beq	2f
+	setup_region r0, r5, r6, MPU_INSTR_SIDE
+2:	isb
+
+	mrc	p15, 0, r0, c0, c0, 4		@ Reevaluate the MPUIR
+	cmp	r4, #0
+	bgt	1b
 
 	/* Enable the MPU */
 	mrc	p15, 0, r0, c1, c0, 0		@ Read SCTLR
-	bic     r0, r0, #CR_BR			@ Disable the 'default mem-map'
+	bic	r0, r0, #CR_BR			@ Disable the 'default mem-map'
 	orr	r0, r0, #CR_M			@ Set SCTRL.M (MPU on)
 	mcr	p15, 0, r0, c1, c0, 0		@ Enable MPU
 	isb
+
 	ret	lr
-ENDPROC(__setup_mpu)
-#endif
+ENDPROC(__secondary_setup_mpu)
+
+#endif /* CONFIG_SMP */
+#endif /* CONFIG_ARM_MPU */
 #include "head-common.S"

arch/arm/kernel/setup.c

···
 	mdesc = setup_machine_fdt(__atags_pointer);
 	if (!mdesc)
 		mdesc = setup_machine_tags(__atags_pointer, __machine_arch_type);
+	if (!mdesc) {
+		early_print("\nError: invalid dtb and unrecognized/unsupported machine ID\n");
+		early_print("  r1=0x%08x, r2=0x%08x\n", __machine_arch_type,
+			    __atags_pointer);
+		if (__atags_pointer)
+			early_print("  r2[]=%*ph\n", 16,
+				    phys_to_virt(__atags_pointer));
+		dump_machine_table();
+	}
+
 	machine_desc = mdesc;
 	machine_name = mdesc->name;
 	dump_stack_set_arch_desc("%s", mdesc->name);

arch/arm/kernel/signal.c

···
 #include <asm/elf.h>
 #include <asm/cacheflush.h>
 #include <asm/traps.h>
-#include <asm/ucontext.h>
 #include <asm/unistd.h>
 #include <asm/vfp.h>
 
-extern const unsigned long sigreturn_codes[7];
+#include "signal.h"
+
+extern const unsigned long sigreturn_codes[17];
 
 static unsigned long signal_return_offset;
 
···
 /*
  * Do a signal return; undo the signal stack.  These are aligned to 64-bit.
  */
-struct sigframe {
-	struct ucontext uc;
-	unsigned long retcode[2];
-};
-
-struct rt_sigframe {
-	struct siginfo info;
-	struct sigframe sig;
-};
 
 static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
 {
···
 	     unsigned long __user *rc, void __user *frame)
 {
 	unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler;
+	unsigned long handler_fdpic_GOT = 0;
 	unsigned long retcode;
-	int thumb = 0;
+	unsigned int idx, thumb = 0;
 	unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT);
+	bool fdpic = IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&
+		     (current->personality & FDPIC_FUNCPTRS);
+
+	if (fdpic) {
+		unsigned long __user *fdpic_func_desc =
+					(unsigned long __user *)handler;
+		if (__get_user(handler, &fdpic_func_desc[0]) ||
+		    __get_user(handler_fdpic_GOT, &fdpic_func_desc[1]))
+			return 1;
+	}
 
 	cpsr |= PSR_ENDSTATE;
 
···
 
 	if (ksig->ka.sa.sa_flags & SA_RESTORER) {
 		retcode = (unsigned long)ksig->ka.sa.sa_restorer;
+		if (fdpic) {
+			/*
+			 * We need code to load the function descriptor.
+			 * That code follows the standard sigreturn code
+			 * (6 words), and is made of 3 + 2 words for each
+			 * variant. The 4th copied word is the actual FD
+			 * address that the assembly code expects.
+			 */
+			idx = 6 + thumb * 3;
+			if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+				idx += 5;
+			if (__put_user(sigreturn_codes[idx],   rc  ) ||
+			    __put_user(sigreturn_codes[idx+1], rc+1) ||
+			    __put_user(sigreturn_codes[idx+2], rc+2) ||
+			    __put_user(retcode,                rc+3))
+				return 1;
+			goto rc_finish;
+		}
 	} else {
-		unsigned int idx = thumb << 1;
-
+		idx = thumb << 1;
 		if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 			idx += 3;
 
···
 		    __put_user(sigreturn_codes[idx+1], rc+1))
 			return 1;
 
+rc_finish:
 #ifdef CONFIG_MMU
 		if (cpsr & MODE32_BIT) {
 			struct mm_struct *mm = current->mm;
···
 			 * the return code written onto the stack.
 			 */
 			flush_icache_range((unsigned long)rc,
-					   (unsigned long)(rc + 2));
+					   (unsigned long)(rc + 3));
 
 			retcode = ((unsigned long)rc) + thumb;
 		}
···
 	regs->ARM_sp = (unsigned long)frame;
 	regs->ARM_lr = retcode;
 	regs->ARM_pc = handler;
+	if (fdpic)
+		regs->ARM_r9 = handler_fdpic_GOT;
 	regs->ARM_cpsr = cpsr;
 
 	return 0;

arch/arm/kernel/signal.h

···
+#include <asm/ucontext.h>
+
+struct sigframe {
+	struct ucontext uc;
+	unsigned long retcode[4];
+};
+
+struct rt_sigframe {
+	struct siginfo info;
+	struct sigframe sig;
+};

arch/arm/kernel/sigreturn_codes.S

···
  * GNU General Public License for more details.
  */
 
+#include <asm/assembler.h>
+#include <asm/asm-offsets.h>
 #include <asm/unistd.h>
 
 /*
···
 	.org	sigreturn_codes + 12 * (\n) + 8
 	.thumb
 	.endm
+
+	.macro arm_fdpic_slot n
+	.org	sigreturn_codes + 24 + 20 * (\n)
+ARM_OK(	.arm	)
+	.endm
+
+	.macro thumb_fdpic_slot n
+	.org	sigreturn_codes + 24 + 20 * (\n) + 12
+	.thumb
+	.endm
+
 
 #if __LINUX_ARM_ARCH__ <= 4
 	/*
···
 	movs	r7, #(__NR_rt_sigreturn - __NR_SYSCALL_BASE)
 	swi	#0
 
+	/* ARM sigreturn restorer FDPIC bounce code snippet */
+	arm_fdpic_slot 0
+ARM_OK(	ldr	r3, [sp, #SIGFRAME_RC3_OFFSET] )
+ARM_OK(	ldmia	r3, {r3, r9} )
+#ifdef CONFIG_ARM_THUMB
+ARM_OK(	bx	r3 )
+#else
+ARM_OK(	ret	r3 )
+#endif
+
+	/* Thumb sigreturn restorer FDPIC bounce code snippet */
+	thumb_fdpic_slot 0
+	ldr	r3, [sp, #SIGFRAME_RC3_OFFSET]
+	ldmia	r3, {r2, r3}
+	mov	r9, r3
+	bx	r2
+
+	/* ARM sigreturn_rt restorer FDPIC bounce code snippet */
+	arm_fdpic_slot 1
+ARM_OK(	ldr	r3, [sp, #RT_SIGFRAME_RC3_OFFSET] )
+ARM_OK(	ldmia	r3, {r3, r9} )
+#ifdef CONFIG_ARM_THUMB
+ARM_OK(	bx	r3 )
+#else
+ARM_OK(	ret	r3 )
+#endif
+
+	/* Thumb sigreturn_rt restorer FDPIC bounce code snippet */
+	thumb_fdpic_slot 1
+	ldr	r3, [sp, #RT_SIGFRAME_RC3_OFFSET]
+	ldmia	r3, {r2, r3}
+	mov	r9, r3
+	bx	r2
+
 	/*
-	 * Note on addtional space: setup_return in signal.c
-	 * algorithm uses two words copy regardless whether
-	 * it is thumb case or not, so we need additional
-	 * word after real last entry.
+	 * Note on additional space: setup_return in signal.c
+	 * always copies the same number of words regardless whether
+	 * it is thumb case or not, so we need one additional padding
+	 * word after the last entry.
 	 */
-	arm_slot 2
 	.space	4
 
 	.size	sigreturn_codes, . - sigreturn_codes

arch/arm/kernel/smp.c

···
 	 */
 	secondary_data.stack = task_stack_page(idle) + THREAD_START_SP;
 #ifdef CONFIG_ARM_MPU
-	secondary_data.mpu_rgn_szr = mpu_rgn_info.rgns[MPU_RAM_REGION].drsr;
+	secondary_data.mpu_rgn_info = &mpu_rgn_info;
 #endif
 
 #ifdef CONFIG_MMU

arch/arm/kernel/traps.c

···
 		set_tls(regs->ARM_r0);
 		return 0;
 
+	case NR(get_tls):
+		return current_thread_info()->tp_value[0];
+
 	default:
 		/* Calls 9f00xx..9f07ff are defined to return -ENOSYS
 		   if not implemented, rather than raising SIGILL.  This

arch/arm/kernel/vmlinux-xip.lds.S

···
 /* No __ro_after_init data in the .rodata section - which will always be ro */
 #define RO_AFTER_INIT_DATA
 
+#include <linux/sizes.h>
+
 #include <asm-generic/vmlinux.lds.h>
 #include <asm/cache.h>
 #include <asm/thread_info.h>
···
 		*(.text.fixup)
 		*(__ex_table)
 #endif
-#ifndef CONFIG_SMP_ON_UP
 		*(.alt.smp.init)
-#endif
 		*(.discard)
 		*(.discard.*)
 	}
···
 		*(.taglist.init)
 		__tagtable_end = .;
 	}
-#ifdef CONFIG_SMP_ON_UP
-	.init.smpalt : {
-		__smpalt_begin = .;
-		*(.alt.smp.init)
-		__smpalt_end = .;
-	}
-#endif
-	.init.pv_table : {
-		__pv_table_begin = .;
-		*(.pv_table)
-		__pv_table_end = .;
-	}
-	.init.data : {
+	.init.rodata : {
 		INIT_SETUP(16)
 		INIT_CALLS
 		CON_INITCALL
···
 		INIT_RAM_FS
 	}
 
+#ifdef CONFIG_ARM_MPU
+	. = ALIGN(SZ_128K);
+#endif
+	_exiprom = .;			/* End of XIP ROM area */
+
+/*
+ * From this point, stuff is considered writable and will be copied to RAM
+ */
+	__data_loc = ALIGN(4);		/* location in file */
+	. = PAGE_OFFSET + TEXT_OFFSET;	/* location in memory */
+#undef LOAD_OFFSET
+#define LOAD_OFFSET (PAGE_OFFSET + TEXT_OFFSET - __data_loc)
+
+	. = ALIGN(THREAD_SIZE);
+	_sdata = .;
+	RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+	.data.ro_after_init : AT(ADDR(.data.ro_after_init) - LOAD_OFFSET) {
+		*(.data..ro_after_init)
+	}
+	_edata = .;
+
+	. = ALIGN(PAGE_SIZE);
+	__init_begin = .;
+	.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
+		INIT_DATA
+	}
+	.exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
+		ARM_EXIT_KEEP(EXIT_DATA)
+	}
 #ifdef CONFIG_SMP
 	PERCPU_SECTION(L1_CACHE_BYTES)
 #endif
 
-	_exiprom = .;			/* End of XIP ROM area */
-	__data_loc = ALIGN(4);		/* location in binary */
-	. = PAGE_OFFSET + TEXT_OFFSET;
+	/*
+	 * End of copied data. We need a dummy section to get its LMA.
+	 * Also located before final ALIGN() as trailing padding is not stored
+	 * in the resulting binary file and useless to copy.
+	 */
+	.data.endmark : AT(ADDR(.data.endmark) - LOAD_OFFSET) { }
+	_edata_loc = LOADADDR(.data.endmark);
 
-	.data : AT(__data_loc) {
-		_data = .;		/* address in memory */
-		_sdata = .;
-
-		/*
-		 * first, the init task union, aligned
-		 * to an 8192 byte boundary.
-		 */
-		INIT_TASK_DATA(THREAD_SIZE)
-
-		. = ALIGN(PAGE_SIZE);
-		__init_begin = .;
-		INIT_DATA
-		ARM_EXIT_KEEP(EXIT_DATA)
-		. = ALIGN(PAGE_SIZE);
-		__init_end = .;
-
-		*(.data..ro_after_init)
-
-		NOSAVE_DATA
-		CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES)
-		READ_MOSTLY_DATA(L1_CACHE_BYTES)
-
-		/*
-		 * and the usual data section
-		 */
-		DATA_DATA
-		CONSTRUCTORS
-
-		_edata = .;
-	}
-	_edata_loc = __data_loc + SIZEOF(.data);
-
-	BUG_TABLE
+	. = ALIGN(PAGE_SIZE);
+	__init_end = .;
 
 #ifdef CONFIG_HAVE_TCM
         /*
···
 	}
 #endif
 
-	BSS_SECTION(0, 0, 0)
+	BSS_SECTION(0, 0, 8)
 	_end = .;
 
 	STABS_DEBUG
···
  */
 ASSERT(__hyp_idmap_text_end - (__hyp_idmap_text_start & PAGE_MASK) <= PAGE_SIZE,
 	"HYP init code too big or misaligned")
+
+#ifdef CONFIG_XIP_DEFLATED_DATA
+/*
+ * The .bss is used as a stack area for __inflate_kernel_data() whose stack
+ * frame is 9568 bytes. Make sure it has extra room left.
+ */
+ASSERT((_end - __bss_start) >= 12288, ".bss too small for CONFIG_XIP_DEFLATED_DATA")
+#endif
+
+#ifdef CONFIG_ARM_MPU
+/*
+ * Due to PMSAv7 restriction on base address and size we have to
+ * enforce minimal alignment restrictions. It was seen that weaker
+ * alignment restriction on _xiprom will likely force XIP address
+ * space spawns multiple MPU regions thus it is likely we run in
+ * situation when we are reprogramming MPU region we run on with
+ * something which doesn't cover reprogramming code itself, so as soon
+ * as we update MPU settings we'd immediately try to execute straight
+ * from background region which is XN.
+ * It seem that alignment in 1M should suit most users.
+ * _exiprom is aligned as 1/8 of 1M so can be covered by subregion
+ * disable
+ */
+ASSERT(!(_xiprom & (SZ_1M - 1)), "XIP start address may cause MPU programming issues")
+ASSERT(!(_exiprom & (SZ_128K - 1)), "XIP end address may cause MPU programming issues")
+#endif

arch/arm/kernel/vmlinux.lds.S

···
 		*(.pv_table)
 		__pv_table_end = .;
 	}
-	.init.data : {
-		INIT_DATA
-		INIT_SETUP(16)
-		INIT_CALLS
-		CON_INITCALL
-		SECURITY_INITCALL
-		INIT_RAM_FS
-	}
+
+	INIT_DATA_SECTION(16)
+
 	.exit.data : {
 		ARM_EXIT_KEEP(EXIT_DATA)
 	}
···
 	. = ALIGN(THREAD_SIZE);
 #endif
 	__init_end = .;
-	__data_loc = .;
 
-	.data : AT(__data_loc) {
-		_data = .;		/* address in memory */
-		_sdata = .;
-
-		/*
-		 * first, the init task union, aligned
-		 * to an 8192 byte boundary.
-		 */
-		INIT_TASK_DATA(THREAD_SIZE)
-
-		NOSAVE_DATA
-		CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES)
-		READ_MOSTLY_DATA(L1_CACHE_BYTES)
-
-		/*
-		 * and the usual data section
-		 */
-		DATA_DATA
-		CONSTRUCTORS
-
-		_edata = .;
-	}
-	_edata_loc = __data_loc + SIZEOF(.data);
-
-	BUG_TABLE
+	_sdata = .;
+	RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+	_edata = .;
 
 #ifdef CONFIG_HAVE_TCM
         /*

arch/arm/mm/Makefile

···
 
 ifneq ($(CONFIG_MMU),y)
 obj-y				+= nommu.o
+obj-$(CONFIG_ARM_MPU)		+= pmsa-v7.o
 endif
 
 obj-$(CONFIG_ARM_PTDUMP)	+= dump.o

arch/arm/mm/dma-mapping.c

···
 }
 
 #define DEFAULT_DMA_COHERENT_POOL_SIZE	SZ_256K
-static struct gen_pool *atomic_pool;
+static struct gen_pool *atomic_pool __ro_after_init;
 
-static size_t atomic_pool_size = DEFAULT_DMA_COHERENT_POOL_SIZE;
+static size_t atomic_pool_size __initdata = DEFAULT_DMA_COHERENT_POOL_SIZE;
 
 static int __init early_coherent_pool(char *p)
 {
···
 	return 0;
 }
 early_param("coherent_pool", early_coherent_pool);
-
-void __init init_dma_coherent_pool_size(unsigned long size)
-{
-	/*
-	 * Catch any attempt to set the pool size too late.
-	 */
-	BUG_ON(atomic_pool);
-
-	/*
-	 * Set architecture specific coherent pool size only if
-	 * it has not been changed by kernel command line parameter.
-	 */
-	if (atomic_pool_size == DEFAULT_DMA_COHERENT_POOL_SIZE)
-		atomic_pool_size = size;
-}
 
 /*
  * Initialise the coherent pool for atomic allocations.
···
 
 		gen_pool_set_algo(atomic_pool,
 				gen_pool_first_fit_order_align,
-				(void *)PAGE_SHIFT);
+				NULL);
 		pr_info("DMA: preallocated %zu KiB pool for atomic coherent allocations\n",
 		       atomic_pool_size / 1024);
 		return 0;

arch/arm/mm/init.c

···
 	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
 	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
 #endif
-
-	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
-		extern int sysctl_overcommit_memory;
-		/*
-		 * On a machine this small we won't get
-		 * anywhere without overcommit, so turn
-		 * it on by default.
-		 */
-		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
-	}
 }
 
 #ifdef CONFIG_STRICT_KERNEL_RWX

arch/arm/mm/nommu.c

···
 
 #ifdef CONFIG_ARM_MPU
 struct mpu_rgn_info mpu_rgn_info;
-
-/* Region number */
-static void rgnr_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c2, 0" : : "r" (v));
-}
-
-/* Data-side / unified region attributes */
-
-/* Region access control register */
-static void dracr_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c1, 4" : : "r" (v));
-}
-
-/* Region size register */
-static void drsr_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c1, 2" : : "r" (v));
-}
-
-/* Region base address register */
-static void drbar_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c1, 0" : : "r" (v));
-}
-
-static u32 drbar_read(void)
-{
-	u32 v;
-	asm("mrc        p15, 0, %0, c6, c1, 0" : "=r" (v));
-	return v;
-}
-/* Optional instruction-side region attributes */
-
-/* I-side Region access control register */
-static void iracr_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c1, 5" : : "r" (v));
-}
-
-/* I-side Region size register */
-static void irsr_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c1, 3" : : "r" (v));
-}
-
-/* I-side Region base address register */
-static void irbar_write(u32 v)
-{
-	asm("mcr        p15, 0, %0, c6, c1, 1" : : "r" (v));
-}
-
-static unsigned long irbar_read(void)
-{
-	unsigned long v;
-	asm("mrc        p15, 0, %0, c6, c1, 1" : "=r" (v));
-	return v;
-}
-
-/* MPU initialisation functions */
-void __init adjust_lowmem_bounds_mpu(void)
-{
-	phys_addr_t phys_offset = PHYS_OFFSET;
-	phys_addr_t aligned_region_size, specified_mem_size, rounded_mem_size;
-	struct memblock_region *reg;
-	bool first = true;
-	phys_addr_t mem_start;
-	phys_addr_t mem_end;
-
-	for_each_memblock(memory, reg) {
-		if (first) {
-			/*
-			 * Initially only use memory continuous from
-			 * PHYS_OFFSET */
-			if (reg->base != phys_offset)
-				panic("First memory bank must be contiguous from PHYS_OFFSET");
-
-			mem_start = reg->base;
-			mem_end = reg->base + reg->size;
-			specified_mem_size = reg->size;
-			first = false;
-		} else {
-			/*
-			 * memblock auto merges contiguous blocks, remove
-			 * all blocks afterwards in one go (we can't remove
-			 * blocks separately while iterating)
-			 */
-			pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
-				  &mem_end, &reg->base);
-			memblock_remove(reg->base, 0 - reg->base);
-			break;
-		}
-	}
-
-	/*
-	 * MPU has curious alignment requirements: Size must be power of 2, and
-	 * region start must be aligned to the region size
-	 */
-	if (phys_offset != 0)
-		pr_info("PHYS_OFFSET != 0 => MPU Region size constrained by alignment requirements\n");
-
-	/*
-	 * Maximum aligned region might overflow phys_addr_t if phys_offset is
-	 * 0. Hence we keep everything below 4G until we take the smaller of
-	 * the aligned_region_size and rounded_mem_size, one of which is
-	 * guaranteed to be smaller than the maximum physical address.
-	 */
-	aligned_region_size = (phys_offset - 1) ^ (phys_offset);
-	/* Find the max power-of-two sized region that fits inside our bank */
-	rounded_mem_size = (1 <<  __fls(specified_mem_size)) - 1;
-
-	/* The actual region size is the smaller of the two */
-	aligned_region_size = aligned_region_size < rounded_mem_size
-				? aligned_region_size + 1
-				: rounded_mem_size + 1;
-
-	if (aligned_region_size != specified_mem_size) {
-		pr_warn("Truncating memory from %pa to %pa (MPU region constraints)",
-				&specified_mem_size, &aligned_region_size);
-		memblock_remove(mem_start + aligned_region_size,
-				specified_mem_size - aligned_region_size);
-
-		mem_end = mem_start + aligned_region_size;
-	}
-
-	pr_debug("MPU Region from %pa size %pa (end %pa))\n",
-		&phys_offset, &aligned_region_size, &mem_end);
-
-}
-
-static int mpu_present(void)
-{
-	return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7);
-}
-
-static int mpu_max_regions(void)
-{
-	/*
-	 * We don't support a different number of I/D side regions so if we
-	 * have separate instruction and data memory maps then return
-	 * whichever side has a smaller number of supported regions.
-	 */
-	u32 dregions, iregions, mpuir;
-	mpuir = read_cpuid(CPUID_MPUIR);
-
-	dregions = iregions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
-
-	/* Check for separate d-side and i-side memory maps */
-	if (mpuir & MPUIR_nU)
-		iregions = (mpuir & MPUIR_IREGION_SZMASK) >> MPUIR_IREGION;
-
-	/* Use the smallest of the two maxima */
-	return min(dregions, iregions);
-}
-
-static int mpu_iside_independent(void)
-{
-	/* MPUIR.nU specifies whether there is *not* a unified memory map */
-	return read_cpuid(CPUID_MPUIR) & MPUIR_nU;
-}
-
-static int mpu_min_region_order(void)
-{
-	u32 drbar_result, irbar_result;
-	/* We've kept a region free for this probing */
-	rgnr_write(MPU_PROBE_REGION);
-	isb();
-	/*
-	 * As per ARM ARM, write 0xFFFFFFFC to DRBAR to find the minimum
-	 * region order
-	*/
-	drbar_write(0xFFFFFFFC);
-	drbar_result = irbar_result = drbar_read();
-	drbar_write(0x0);
-	/* If the MPU is non-unified, we use the larger of the two minima*/
-	if (mpu_iside_independent()) {
-		irbar_write(0xFFFFFFFC);
-		irbar_result = irbar_read();
-		irbar_write(0x0);
-	}
-	isb(); /* Ensure that MPU region operations have completed */
-	/* Return whichever result is larger */
-	return __ffs(max(drbar_result, irbar_result));
-}
-
-static int mpu_setup_region(unsigned int number, phys_addr_t start,
-			unsigned int size_order, unsigned int properties)
-{
-	u32 size_data;
-
-	/* We kept a region free for probing resolution of MPU regions*/
-	if (number > mpu_max_regions() || number == MPU_PROBE_REGION)
-		return -ENOENT;
-
-	if (size_order > 32)
-		return -ENOMEM;
-
-	if (size_order < mpu_min_region_order())
-		return -ENOMEM;
-
-	/* Writing N to bits 5:1 (RSR_SZ)  specifies region size 2^N+1 */
-	size_data = ((size_order - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN;
-
-	dsb(); /* Ensure all previous data accesses occur with old mappings */
-	rgnr_write(number);
-	isb();
-	drbar_write(start);
-	dracr_write(properties);
-	isb(); /* Propagate properties before enabling region */
-	drsr_write(size_data);
-
-	/* Check for independent I-side registers */
-	if (mpu_iside_independent()) {
-		irbar_write(start);
-		iracr_write(properties);
-		isb();
-		irsr_write(size_data);
-	}
-	isb();
-
-	/* Store region info (we treat i/d side the same, so only store d) */
-	mpu_rgn_info.rgns[number].dracr = properties;
-	mpu_rgn_info.rgns[number].drbar = start;
-	mpu_rgn_info.rgns[number].drsr = size_data;
-	return 0;
-}
-
-/*
-* Set up default MPU regions, doing nothing if there is no MPU
-*/
-void __init mpu_setup(void)
-{
-	int region_err;
-	if (!mpu_present())
-		return;
-
-	region_err = mpu_setup_region(MPU_RAM_REGION, PHYS_OFFSET,
-					ilog2(memblock.memory.regions[0].size),
-					MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL);
-	if (region_err) {
-		panic("MPU region initialization failure! %d", region_err);
-	} else {
-		pr_info("Using ARMv7 PMSA Compliant MPU. "
-			 "Region independence: %s, Max regions: %d\n",
-			mpu_iside_independent() ? "Yes" : "No",
-			mpu_max_regions());
-	}
-}
-#else
-static void adjust_lowmem_bounds_mpu(void) {}
-static void __init mpu_setup(void) {}
-#endif /* CONFIG_ARM_MPU */
+#endif
 
 #ifdef CONFIG_CPU_CP15
 #ifdef CONFIG_CPU_HIGH_VECTOR

arch/arm/mm/pmsa-v7.c

···
+/*
+ * Based on linux/arch/arm/mm/nommu.c
+ *
+ * ARM PMSAv7 supporting functions.
+ */
+
+#include <linux/bitops.h>
+#include <linux/memblock.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/cputype.h>
+#include <asm/mpu.h>
+#include <asm/sections.h>
+
+#include "mm.h"
+
+struct region {
+	phys_addr_t base;
+	phys_addr_t size;
+	unsigned long subreg;
+};
+
+static struct region __initdata mem[MPU_MAX_REGIONS];
+#ifdef CONFIG_XIP_KERNEL
+static struct region __initdata xip[MPU_MAX_REGIONS];
+#endif
+
+static unsigned int __initdata mpu_min_region_order;
+static unsigned int __initdata mpu_max_regions;
+
+static int __init __mpu_min_region_order(void);
+static int __init __mpu_max_regions(void);
+
+#ifndef CONFIG_CPU_V7M
+
+#define DRBAR	__ACCESS_CP15(c6, 0, c1, 0)
+#define IRBAR	__ACCESS_CP15(c6, 0, c1, 1)
+#define DRSR	__ACCESS_CP15(c6, 0, c1, 2)
+#define IRSR	__ACCESS_CP15(c6, 0, c1, 3)
+#define DRACR	__ACCESS_CP15(c6, 0, c1, 4)
+#define IRACR	__ACCESS_CP15(c6, 0, c1, 5)
+#define RNGNR	__ACCESS_CP15(c6, 0, c2, 0)
+
+/* Region number */
+static inline void rgnr_write(u32 v)
+{
+	write_sysreg(v, RNGNR);
+}
+
+/* Data-side / unified region attributes */
+
+/* Region access control register */
+static inline void dracr_write(u32 v)
+{
+	write_sysreg(v, DRACR);
+}
+
+/* Region size register */
+static inline void drsr_write(u32 v)
+{
+	write_sysreg(v, DRSR);
+}
+
+/* Region base address register */
+static inline void drbar_write(u32 v)
+{
+	write_sysreg(v, DRBAR);
+}
+
+static inline u32 drbar_read(void)
+{
+	return read_sysreg(DRBAR);
+}
+/* Optional instruction-side region attributes */
+
+/* I-side Region access control register */
+static inline void iracr_write(u32 v)
+{
+	write_sysreg(v, IRACR);
+}
+
+/* I-side Region size register */
+static inline void irsr_write(u32 v)
+{
+	write_sysreg(v, IRSR);
+}
+
+/* I-side Region base address register */
+static inline void irbar_write(u32 v)
+{
+	write_sysreg(v, IRBAR);
+}
+
+static inline u32 irbar_read(void)
+{
+	return read_sysreg(IRBAR);
+}
+
+#else
+
+static inline void rgnr_write(u32 v)
+{
+	writel_relaxed(v, BASEADDR_V7M_SCB + MPU_RNR);
+}
+
+/* Data-side / unified region attributes */
+
+/* Region access control register */
+static inline void dracr_write(u32 v)
+{
+	u32 rsr = readl_relaxed(BASEADDR_V7M_SCB + MPU_RASR) & GENMASK(15, 0);
+
+	writel_relaxed((v << 16) | rsr, BASEADDR_V7M_SCB + MPU_RASR);
+}
+
+/* Region size register */
+static inline void drsr_write(u32 v)
+{
+	u32 racr = readl_relaxed(BASEADDR_V7M_SCB + MPU_RASR) & GENMASK(31, 16);
+
+	writel_relaxed(v | racr, BASEADDR_V7M_SCB + MPU_RASR);
+}
+
+/* Region base address register */
+static inline void drbar_write(u32 v)
+{
+	writel_relaxed(v, BASEADDR_V7M_SCB + MPU_RBAR);
+}
+
+static inline u32 drbar_read(void)
+{
+	return readl_relaxed(BASEADDR_V7M_SCB + MPU_RBAR);
+}
+
+/* ARMv7-M only supports a unified MPU, so I-side operations are nop */
+
+static inline void iracr_write(u32 v) {}
+static inline void irsr_write(u32 v) {}
+static inline void irbar_write(u32 v) {}
+static inline unsigned long irbar_read(void) {return 0;}
+
+#endif
+
+static int __init mpu_present(void)
+{
+	return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7);
+}
+
+static bool __init try_split_region(phys_addr_t base, phys_addr_t size, struct region *region)
+{
+	unsigned long  subreg, bslots, sslots;
+	phys_addr_t abase = base & ~(size - 1);
+	phys_addr_t asize = base + size - abase;
+	phys_addr_t p2size = 1 << __fls(asize);
+	phys_addr_t bdiff, sdiff;
+
+	if (p2size != asize)
+		p2size *= 2;
+
+	bdiff = base - abase;
+	sdiff = p2size - asize;
+	subreg = p2size / MPU_NR_SUBREGS;
+
+	if ((bdiff % subreg) || (sdiff % subreg))
+		return false;
+
+	bslots = bdiff / subreg;
+	sslots = sdiff / subreg;
+
+	if (bslots || sslots) {
+		int i;
+
+		if (subreg < MPU_MIN_SUBREG_SIZE)
+			return false;
+
+		if (bslots + sslots > MPU_NR_SUBREGS)
+			return false;
+
+		for (i = 0; i < bslots; i++)
+			_set_bit(i, &region->subreg);
+
+		for (i = 1; i <= sslots; i++)
+			_set_bit(MPU_NR_SUBREGS - i, &region->subreg);
+	}
+
+	region->base = abase;
+	region->size = p2size;
+
+	return true;
+}
+
+static int __init allocate_region(phys_addr_t base, phys_addr_t size,
+				  unsigned int limit, struct region *regions)
+{
+	int count = 0;
+	phys_addr_t diff = size;
+	int attempts = MPU_MAX_REGIONS;
+
+	while (diff) {
+		/* Try cover region as is (maybe with help of subregions) */
+		if (try_split_region(base, size, &regions[count])) {
+			count++;
+			base += size;
+			diff -= size;
+			size = diff;
+		} else {
+			/*
+			 * Maximum aligned region might overflow phys_addr_t
+			 * if "base" is 0. Hence we keep everything below 4G
+			 * until we take the smaller of the aligned region
+			 * size ("asize") and rounded region size ("p2size"),
+			 * one of which is guaranteed to be smaller than the
+			 * maximum physical address.
+			 */
+			phys_addr_t asize = (base - 1) ^ base;
+			phys_addr_t p2size = (1 <<  __fls(diff)) - 1;
+
+			size = asize < p2size ? asize + 1 : p2size + 1;
+		}
+
+		if (count > limit)
+			break;
+
+		if (!attempts)
+			break;
+
+		attempts--;
+	}
+
+	return count;
+}
+
+/* MPU initialisation functions */
+void __init adjust_lowmem_bounds_mpu(void)
+{
+	phys_addr_t  specified_mem_size = 0, total_mem_size = 0;
+	struct memblock_region *reg;
+	bool first = true;
+	phys_addr_t mem_start;
+	phys_addr_t mem_end;
+	unsigned int mem_max_regions;
+	int num, i;
+
+	if (!mpu_present())
+		return;
+
+	/* Free-up MPU_PROBE_REGION */
+	mpu_min_region_order = __mpu_min_region_order();
+
+	/* How many regions are supported */
+	mpu_max_regions = __mpu_max_regions();
+
+	mem_max_regions = min((unsigned int)MPU_MAX_REGIONS, mpu_max_regions);
+
+	/* We need to keep one slot for background region */
+	mem_max_regions--;
+
+#ifndef CONFIG_CPU_V7M
+	/* ... and one for vectors */
+	mem_max_regions--;
+#endif
+
+#ifdef CONFIG_XIP_KERNEL
+	/* plus some regions to cover XIP ROM */
+	num = allocate_region(CONFIG_XIP_PHYS_ADDR, __pa(_exiprom) - CONFIG_XIP_PHYS_ADDR,
+			      mem_max_regions, xip);
+
+	mem_max_regions -= num;
+#endif
+
+	for_each_memblock(memory, reg) {
+		if (first) {
+			phys_addr_t phys_offset = PHYS_OFFSET;
+
+			/*
+			 * Initially only use memory continuous from
+			 * PHYS_OFFSET */
+			if (reg->base != phys_offset)
+				panic("First memory bank must be contiguous from PHYS_OFFSET");
+
+			mem_start = reg->base;
+			mem_end = reg->base + reg->size;
+			specified_mem_size = reg->size;
+			first = false;
+		} else {
+			/*
+			 * memblock auto merges contiguous blocks, remove
+			 * all blocks afterwards in one go (we can't remove
+			 * blocks separately while iterating)
+			 */
+			pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
+				  &mem_end, &reg->base);
+			memblock_remove(reg->base, 0 - reg->base);
+			break;
+		}
+	}
+
+	num = allocate_region(mem_start, specified_mem_size, mem_max_regions, mem);
+
+	for (i = 0; i < num; i++) {
+		unsigned long  subreg = mem[i].size / MPU_NR_SUBREGS;
+
+		total_mem_size += mem[i].size - subreg * hweight_long(mem[i].subreg);
+
+		pr_debug("MPU: base %pa size %pa disable subregions: %*pbl\n",
+			 &mem[i].base, &mem[i].size, MPU_NR_SUBREGS, &mem[i].subreg);
+	}
+
+	if (total_mem_size != specified_mem_size) {
+		pr_warn("Truncating memory from %pa to %pa (MPU region constraints)",
+				&specified_mem_size, &total_mem_size);
+		memblock_remove(mem_start + total_mem_size,
+				specified_mem_size - total_mem_size);
+	}
+}
+
+static int __init __mpu_max_regions(void)
+{
+	/*
+	 * We don't support a different number of I/D side regions so if we
+	 * have separate instruction and data memory maps then return
+	 * whichever side has a smaller number of supported regions.
+	 */
+	u32 dregions, iregions, mpuir;
+
+	mpuir = read_cpuid_mputype();
+
+	dregions = iregions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION;
+
+	/* Check for separate d-side and i-side memory maps */
+	if (mpuir & MPUIR_nU)
+		iregions = (mpuir & MPUIR_IREGION_SZMASK) >> MPUIR_IREGION;
+
+	/* Use the smallest of the two maxima */
+	return min(dregions, iregions);
+}
+
+static int __init mpu_iside_independent(void)
+{
+	/* MPUIR.nU specifies whether there is *not* a unified memory map */
+	return read_cpuid_mputype() & MPUIR_nU;
+}
+
+static int __init __mpu_min_region_order(void)
+{
+	u32 drbar_result, irbar_result;
+
+	/* We've kept a region free for this probing */
+	rgnr_write(MPU_PROBE_REGION);
+	isb();
+	/*
+	 * As per ARM ARM, write 0xFFFFFFFC to DRBAR to find the minimum
+	 * region order
+	*/
+	drbar_write(0xFFFFFFFC);
+	drbar_result = irbar_result = drbar_read();
+	drbar_write(0x0);
+	/* If the MPU is non-unified, we use the larger of the two minima*/
+	if (mpu_iside_independent()) {
+		irbar_write(0xFFFFFFFC);
+		irbar_result = irbar_read();
+		irbar_write(0x0);
+	}
+	isb(); /* Ensure that MPU region operations have completed */
+	/* Return whichever result is larger */
+
+	return __ffs(max(drbar_result, irbar_result));
+}
+
+static int __init mpu_setup_region(unsigned int number, phys_addr_t start,
+				   unsigned int size_order, unsigned int properties,
+				   unsigned int subregions, bool need_flush)
+{
+	u32 size_data;
+
+	/* We kept a region free for probing resolution of MPU regions*/
+	if (number > mpu_max_regions
+	    || number >= MPU_MAX_REGIONS)
+		return -ENOENT;
+
+	if (size_order > 32)
+		return -ENOMEM;
+
+	if (size_order < mpu_min_region_order)
+		return -ENOMEM;
+
+	/* Writing N to bits 5:1 (RSR_SZ)  specifies region size 2^N+1 */
+	size_data = ((size_order - 1) << MPU_RSR_SZ) | 1 << MPU_RSR_EN;
+	size_data |= subregions << MPU_RSR_SD;
+
+	if (need_flush)
+		flush_cache_all();
+
+	dsb(); /* Ensure all previous data accesses occur with old mappings */
+	rgnr_write(number);
+	isb();
+	drbar_write(start);
+	dracr_write(properties);
+	isb(); /* Propagate properties before enabling region */
+	drsr_write(size_data);
+
+	/* Check for independent I-side registers */
+	if (mpu_iside_independent()) {
+		irbar_write(start);
+		iracr_write(properties);
+		isb();
+		irsr_write(size_data);
+	}
+	isb();
+
+	/* Store region info (we treat i/d side the same, so only store d) */
+	mpu_rgn_info.rgns[number].dracr = properties;
+	mpu_rgn_info.rgns[number].drbar = start;
+	mpu_rgn_info.rgns[number].drsr = size_data;
+
+	mpu_rgn_info.used++;
+
+	return 0;
+}
+
+/*
+* Set up default MPU regions, doing nothing if there is no MPU
+*/
+void __init mpu_setup(void)
+{
+	int i, region = 0, err = 0;
+
+	if (!mpu_present())
+		return;
+
+	/* Setup MPU (order is important) */
+
+	/* Background */
+	err |= mpu_setup_region(region++, 0, 32,
+				MPU_ACR_XN | MPU_RGN_STRONGLY_ORDERED | MPU_AP_PL1RW_PL0NA,
+				0, false);
+
+#ifdef CONFIG_XIP_KERNEL
+	/* ROM */
+	for (i = 0; i < ARRAY_SIZE(xip); i++) {
+		/*
+                 * In case we overwrite RAM region we set earlier in
+                 * head-nommu.S (which is cachable) all subsequent
+                 * data access till we setup RAM bellow would be done
+                 * with BG region (which is uncachable), thus we need
+                 * to clean and invalidate cache.
+		 */
+		bool need_flush = region == MPU_RAM_REGION;
+
+		if (!xip[i].size)
+			continue;
+
+		err |= mpu_setup_region(region++, xip[i].base, ilog2(xip[i].size),
+					MPU_AP_PL1RO_PL0NA | MPU_RGN_NORMAL,
+					xip[i].subreg, need_flush);
+	}
+#endif
+
+	/* RAM */
+	for (i = 0; i < ARRAY_SIZE(mem); i++) {
+		if (!mem[i].size)
+			continue;
+
+		err |= mpu_setup_region(region++, mem[i].base, ilog2(mem[i].size),
+					MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL,
+					mem[i].subreg, false);
+	}
+
+	/* Vectors */
+#ifndef CONFIG_CPU_V7M
+	err |= mpu_setup_region(region++, vectors_base, ilog2(2 * PAGE_SIZE),
+				MPU_AP_PL1RW_PL0NA | MPU_RGN_NORMAL,
+				0, false);
+#endif
+	if (err) {
+		panic("MPU region initialization failure! %d", err);
+	} else {
+		pr_info("Using ARMv7 PMSA Compliant MPU. "
+			 "Region independence: %s, Used %d of %d regions\n",
+			mpu_iside_independent() ? "Yes" : "No",
+			mpu_rgn_info.used, mpu_max_regions);
+	}
+}

drivers/pcmcia/sa1111_generic.c

···
 #define IDX_IRQ_S1_READY_NINT	(3)
 #define IDX_IRQ_S1_CD_VALID	(4)
 #define IDX_IRQ_S1_BVD1_STSCHG	(5)
+#define NUM_IRQS		(6)
 
 void sa1111_pcmcia_socket_state(struct soc_pcmcia_socket *skt, struct pcmcia_state *state)
 {
 	struct sa1111_pcmcia_socket *s = to_skt(skt);
-	unsigned long status = sa1111_readl(s->dev->mapbase + PCSR);
+	u32 status = readl_relaxed(s->dev->mapbase + PCSR);
 
 	switch (skt->nr) {
 	case 0:
···
 int sa1111_pcmcia_configure_socket(struct soc_pcmcia_socket *skt, const socket_state_t *state)
 {
 	struct sa1111_pcmcia_socket *s = to_skt(skt);
-	unsigned int pccr_skt_mask, pccr_set_mask, val;
+	u32 pccr_skt_mask, pccr_set_mask, val;
 	unsigned long flags;
 
 	switch (skt->nr) {
···
 		pccr_set_mask |= PCCR_S0_FLT|PCCR_S1_FLT;
 
 	local_irq_save(flags);
-	val = sa1111_readl(s->dev->mapbase + PCCR);
+	val = readl_relaxed(s->dev->mapbase + PCCR);
 	val &= ~pccr_skt_mask;
 	val |= pccr_set_mask & pccr_skt_mask;
-	sa1111_writel(val, s->dev->mapbase + PCCR);
+	writel_relaxed(val, s->dev->mapbase + PCCR);
 	local_irq_restore(flags);
 
 	return 0;
···
 {
 	struct sa1111_pcmcia_socket *s;
 	struct clk *clk;
-	int i, ret = 0;
+	int i, ret = 0, irqs[NUM_IRQS];
 
 	clk = devm_clk_get(&dev->dev, NULL);
 	if (IS_ERR(clk))
 		return PTR_ERR(clk);
+
+	for (i = 0; i < NUM_IRQS; i++) {
+		irqs[i] = sa1111_get_irq(dev, i);
+		if (irqs[i] <= 0)
+			return irqs[i] ? : -ENXIO;
+	}
 
 	ops->socket_state = sa1111_pcmcia_socket_state;
 
···
 		soc_pcmcia_init_one(&s->soc, ops, &dev->dev);
 		s->dev = dev;
 		if (s->soc.nr) {
-			s->soc.socket.pci_irq = dev->irq[IDX_IRQ_S1_READY_NINT];
-			s->soc.stat[SOC_STAT_CD].irq = dev->irq[IDX_IRQ_S1_CD_VALID];
+			s->soc.socket.pci_irq = irqs[IDX_IRQ_S1_READY_NINT];
+			s->soc.stat[SOC_STAT_CD].irq = irqs[IDX_IRQ_S1_CD_VALID];
 			s->soc.stat[SOC_STAT_CD].name = "SA1111 CF card detect";
-			s->soc.stat[SOC_STAT_BVD1].irq = dev->irq[IDX_IRQ_S1_BVD1_STSCHG];
+			s->soc.stat[SOC_STAT_BVD1].irq = irqs[IDX_IRQ_S1_BVD1_STSCHG];
 			s->soc.stat[SOC_STAT_BVD1].name = "SA1111 CF BVD1";
 		} else {
-			s->soc.socket.pci_irq = dev->irq[IDX_IRQ_S0_READY_NINT];
-			s->soc.stat[SOC_STAT_CD].irq = dev->irq[IDX_IRQ_S0_CD_VALID];
+			s->soc.socket.pci_irq = irqs[IDX_IRQ_S0_READY_NINT];
+			s->soc.stat[SOC_STAT_CD].irq = irqs[IDX_IRQ_S0_CD_VALID];
 			s->soc.stat[SOC_STAT_CD].name = "SA1111 PCMCIA card detect";
-			s->soc.stat[SOC_STAT_BVD1].irq = dev->irq[IDX_IRQ_S0_BVD1_STSCHG];
+			s->soc.stat[SOC_STAT_BVD1].irq = irqs[IDX_IRQ_S0_BVD1_STSCHG];
 			s->soc.stat[SOC_STAT_BVD1].name = "SA1111 PCMCIA BVD1";
 		}
 
···
 	/*
 	 * Initialise the suspend state.
 	 */
-	sa1111_writel(PCSSR_S0_SLEEP | PCSSR_S1_SLEEP, base + PCSSR);
-	sa1111_writel(PCCR_S0_FLT | PCCR_S1_FLT, base + PCCR);
+	writel_relaxed(PCSSR_S0_SLEEP | PCSSR_S1_SLEEP, base + PCSSR);
+	writel_relaxed(PCCR_S0_FLT | PCCR_S1_FLT, base + PCCR);
 
 	ret = -ENODEV;
 #ifdef CONFIG_SA1100_BADGE4

fs/Kconfig.binfmt

···
 
 config BINFMT_ELF_FDPIC
 	bool "Kernel support for FDPIC ELF binaries"
-	default y
-	depends on (FRV || BLACKFIN || (SUPERH32 && !MMU) || C6X)
+	default y if !BINFMT_ELF
+	depends on (ARM || FRV || BLACKFIN || (SUPERH32 && !MMU) || C6X)
 	select ELFCORE
 	help
 	  ELF FDPIC binaries are based on ELF, but allow the individual load

fs/binfmt_elf.c

···
 #define user_siginfo_t siginfo_t
 #endif
 
+/* That's for binfmt_elf_fdpic to deal with */
+#ifndef elf_check_fdpic
+#define elf_check_fdpic(ex) false
+#endif
+
 static int load_elf_binary(struct linux_binprm *bprm);
 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
 				int, int, unsigned long);
···
 	if (interp_elf_ex->e_type != ET_EXEC &&
 	    interp_elf_ex->e_type != ET_DYN)
 		goto out;
-	if (!elf_check_arch(interp_elf_ex))
+	if (!elf_check_arch(interp_elf_ex) ||
+	    elf_check_fdpic(interp_elf_ex))
 		goto out;
 	if (!interpreter->f_op->mmap)
 		goto out;
···
 		goto out;
 	if (!elf_check_arch(&loc->elf_ex))
 		goto out;
+	if (elf_check_fdpic(&loc->elf_ex))
+		goto out;
 	if (!bprm->file->f_op->mmap)
 		goto out;
 
···
 		if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
 			goto out_free_dentry;
 		/* Verify the interpreter has a valid arch */
-		if (!elf_check_arch(&loc->interp_elf_ex))
+		if (!elf_check_arch(&loc->interp_elf_ex) ||
+		    elf_check_fdpic(&loc->interp_elf_ex))
 			goto out_free_dentry;
 
 		/* Load the interpreter program headers */
···
 	/* First of all, some simple consistency checks */
 	if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
 	    !elf_check_arch(&elf_ex) || !file->f_op->mmap)
+		goto out;
+	if (elf_check_fdpic(&elf_ex))
 		goto out;
 
 	/* Now read in all of the header information */

fs/binfmt_elf_fdpic.c

···
 				 executable_stack);
 	if (retval < 0)
 		goto error;
+#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
+	retval = arch_setup_additional_pages(bprm, !!interpreter_name);
+	if (retval < 0)
+		goto error;
+#endif
 #endif
 
 	/* load the executable and interpreter into memory */
···
 			if (phdr->p_vaddr >= seg->p_vaddr &&
 			    phdr->p_vaddr + phdr->p_memsz <=
 			    seg->p_vaddr + seg->p_memsz) {
+				Elf32_Dyn __user *dyn;
+				Elf32_Sword d_tag;
+
 				params->dynamic_addr =
 					(phdr->p_vaddr - seg->p_vaddr) +
 					seg->addr;
···
 					goto dynamic_error;
 
 				tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
-				if (((Elf32_Dyn *)
-				     params->dynamic_addr)[tmp - 1].d_tag != 0)
+				dyn = (Elf32_Dyn __user *)params->dynamic_addr;
+				__get_user(d_tag, &dyn[tmp - 1].d_tag);
+				if (d_tag != 0)
 					goto dynamic_error;
 				break;
 			}