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

Pull ARM development updates from Russell King:

 - Make it clear __swp_entry_to_pte() uses PTE_TYPE_FAULT

 - Updates for setting vmalloc size via command line to resolve an issue
   with the 8MiB hole not properly being accounted for, and clean up the
   code.

 - ftrace support for module PLTs

 - Spelling fixes

 - kbuild updates for removing generated files and pattern rules for
   generating files

 - Clang/llvm updates

 - Change the way the kernel is mapped, placing it in vmalloc space
   instead.

 - Remove arm_pm_restart from arm and aarch64.

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (29 commits)
  ARM: 9098/1: ftrace: MODULE_PLT: Fix build problem without DYNAMIC_FTRACE
  ARM: 9097/1: mmu: Declare section start/end correctly
  ARM: 9096/1: Remove arm_pm_restart()
  ARM: 9095/1: ARM64: Remove arm_pm_restart()
  ARM: 9094/1: Register with kernel restart handler
  ARM: 9093/1: drivers: firmwapsci: Register with kernel restart handler
  ARM: 9092/1: xen: Register with kernel restart handler
  ARM: 9091/1: Revert "mm: qsd8x50: Fix incorrect permission faults"
  ARM: 9090/1: Map the lowmem and kernel separately
  ARM: 9089/1: Define kernel physical section start and end
  ARM: 9088/1: Split KERNEL_OFFSET from PAGE_OFFSET
  ARM: 9087/1: kprobes: test-thumb: fix for LLVM_IAS=1
  ARM: 9086/1: syscalls: use pattern rules to generate syscall headers
  ARM: 9085/1: remove unneeded abi parameter to syscallnr.sh
  ARM: 9084/1: simplify the build rule of mach-types.h
  ARM: 9083/1: uncompress: atags_to_fdt: Spelling s/REturn/Return/
  ARM: 9082/1: [v2] mark prepare_page_table as __init
  ARM: 9079/1: ftrace: Add MODULE_PLTS support
  ARM: 9078/1: Add warn suppress parameter to arm_gen_branch_link()
  ARM: 9077/1: PLT: Move struct plt_entries definition to header
  ...

arch/arm/Kconfig.debug

@@ -66,6 +66,8 @@ config UNWINDER_FRAME_POINTER
 config UNWINDER_ARM
 	bool "ARM EABI stack unwinder"
 	depends on AEABI && !FUNCTION_GRAPH_TRACER
+	# https://github.com/ClangBuiltLinux/linux/issues/732
+	depends on !LD_IS_LLD || LLD_VERSION >= 110000
 	select ARM_UNWIND
 	help
 	  This option enables stack unwinding support in the kernel

arch/arm/boot/compressed/Makefile

@@ -100,7 +100,7 @@ targets       := vmlinux vmlinux.lds piggy_data piggy.o \
 		 lib1funcs.o ashldi3.o bswapsdi2.o \
 		 head.o $(OBJS)
 
-clean-files += piggy_data lib1funcs.S ashldi3.S bswapsdi2.S hyp-stub.S
+clean-files += lib1funcs.S ashldi3.S bswapsdi2.S hyp-stub.S
 
 KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
 

arch/arm/boot/compressed/atags_to_fdt.c

@@ -121,7 +121,7 @@ static void hex_str(char *out, uint32_t value)
 /*
  * Convert and fold provided ATAGs into the provided FDT.
  *
- * REturn values:
+ * Return values:
  *    = 0 -> pretend success
  *    = 1 -> bad ATAG (may retry with another possible ATAG pointer)
  *    < 0 -> error from libfdt

arch/arm/include/asm/ftrace.h

@@ -15,6 +15,9 @@ extern void __gnu_mcount_nc(void);
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 struct dyn_arch_ftrace {
+#ifdef CONFIG_ARM_MODULE_PLTS
+	struct module *mod;
+#endif
 };
 
 static inline unsigned long ftrace_call_adjust(unsigned long addr)

arch/arm/include/asm/insn.h

@@ -13,18 +13,18 @@ arm_gen_nop(void)
 }
 
 unsigned long
-__arm_gen_branch(unsigned long pc, unsigned long addr, bool link);
+__arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn);
 
 static inline unsigned long
 arm_gen_branch(unsigned long pc, unsigned long addr)
 {
-	return __arm_gen_branch(pc, addr, false);
+	return __arm_gen_branch(pc, addr, false, true);
 }
 
 static inline unsigned long
-arm_gen_branch_link(unsigned long pc, unsigned long addr)
+arm_gen_branch_link(unsigned long pc, unsigned long addr, bool warn)
 {
-	return __arm_gen_branch(pc, addr, true);
+	return __arm_gen_branch(pc, addr, true, warn);
 }
 
 #endif

arch/arm/include/asm/memory.h

@@ -20,8 +20,14 @@
 #endif
 #include <asm/kasan_def.h>
 
-/* PAGE_OFFSET - the virtual address of the start of the kernel image */
+/*
+ * PAGE_OFFSET: the virtual address of the start of lowmem, memory above
+ *   the virtual address range for userspace.
+ * KERNEL_OFFSET: the virtual address of the start of the kernel image.
+ *   we may further offset this with TEXT_OFFSET in practice.
+ */
 #define PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)
+#define KERNEL_OFFSET		(PAGE_OFFSET)
 
 #ifdef CONFIG_MMU
 
@@ -152,6 +158,13 @@ extern unsigned long vectors_base;
 
 #ifndef __ASSEMBLY__
 
+/*
+ * Physical start and end address of the kernel sections. These addresses are
+ * 2MB-aligned to match the section mappings placed over the kernel.
+ */
+extern u32 kernel_sec_start;
+extern u32 kernel_sec_end;
+
 /*
  * Physical vs virtual RAM address space conversion.  These are
  * private definitions which should NOT be used outside memory.h

arch/arm/include/asm/module.h

@@ -19,8 +19,18 @@ enum {
 };
 #endif
 
+#define PLT_ENT_STRIDE		L1_CACHE_BYTES
+#define PLT_ENT_COUNT		(PLT_ENT_STRIDE / sizeof(u32))
+#define PLT_ENT_SIZE		(sizeof(struct plt_entries) / PLT_ENT_COUNT)
+
+struct plt_entries {
+	u32	ldr[PLT_ENT_COUNT];
+	u32	lit[PLT_ENT_COUNT];
+};
+
 struct mod_plt_sec {
 	struct elf32_shdr	*plt;
+	struct plt_entries	*plt_ent;
 	int			plt_count;
 };
 

arch/arm/include/asm/pgtable.h

@@ -306,7 +306,7 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
 
 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
-#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
+#define __swp_entry_to_pte(swp)	__pte((swp).val | PTE_TYPE_FAULT)
 
 /*
  * It is an error for the kernel to have more swap files than we can

arch/arm/include/asm/system_misc.h

@@ -13,7 +13,6 @@
 extern void cpu_init(void);
 
 void soft_restart(unsigned long);
-extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
 extern void (*arm_pm_idle)(void);
 
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR

arch/arm/kernel/ftrace.c

@@ -68,9 +68,10 @@ int ftrace_arch_code_modify_post_process(void)
 	return 0;
 }
 
-static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
+static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr,
+					 bool warn)
 {
-	return arm_gen_branch_link(pc, addr);
+	return arm_gen_branch_link(pc, addr, warn);
 }
 
 static int ftrace_modify_code(unsigned long pc, unsigned long old,
@@ -104,14 +105,14 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 	int ret;
 
 	pc = (unsigned long)&ftrace_call;
-	new = ftrace_call_replace(pc, (unsigned long)func);
+	new = ftrace_call_replace(pc, (unsigned long)func, true);
 
 	ret = ftrace_modify_code(pc, 0, new, false);
 
 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
 	if (!ret) {
 		pc = (unsigned long)&ftrace_regs_call;
-		new = ftrace_call_replace(pc, (unsigned long)func);
+		new = ftrace_call_replace(pc, (unsigned long)func, true);
 
 		ret = ftrace_modify_code(pc, 0, new, false);
 	}
@@ -124,10 +125,22 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 {
 	unsigned long new, old;
 	unsigned long ip = rec->ip;
+	unsigned long aaddr = adjust_address(rec, addr);
+	struct module *mod = NULL;
+
+#ifdef CONFIG_ARM_MODULE_PLTS
+	mod = rec->arch.mod;
+#endif
 
 	old = ftrace_nop_replace(rec);
 
-	new = ftrace_call_replace(ip, adjust_address(rec, addr));
+	new = ftrace_call_replace(ip, aaddr, !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+	if (!new && mod) {
+		aaddr = get_module_plt(mod, ip, aaddr);
+		new = ftrace_call_replace(ip, aaddr, true);
+	}
+#endif
 
 	return ftrace_modify_code(rec->ip, old, new, true);
 }
@@ -140,9 +153,9 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
 	unsigned long new, old;
 	unsigned long ip = rec->ip;
 
-	old = ftrace_call_replace(ip, adjust_address(rec, old_addr));
+	old = ftrace_call_replace(ip, adjust_address(rec, old_addr), true);
 
-	new = ftrace_call_replace(ip, adjust_address(rec, addr));
+	new = ftrace_call_replace(ip, adjust_address(rec, addr), true);
 
 	return ftrace_modify_code(rec->ip, old, new, true);
 }
@@ -152,12 +165,29 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
 int ftrace_make_nop(struct module *mod,
 		    struct dyn_ftrace *rec, unsigned long addr)
 {
+	unsigned long aaddr = adjust_address(rec, addr);
 	unsigned long ip = rec->ip;
 	unsigned long old;
 	unsigned long new;
 	int ret;
 
-	old = ftrace_call_replace(ip, adjust_address(rec, addr));
+#ifdef CONFIG_ARM_MODULE_PLTS
+	/* mod is only supplied during module loading */
+	if (!mod)
+		mod = rec->arch.mod;
+	else
+		rec->arch.mod = mod;
+#endif
+
+	old = ftrace_call_replace(ip, aaddr,
+				  !IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+	if (!old && mod) {
+		aaddr = get_module_plt(mod, ip, aaddr);
+		old = ftrace_call_replace(ip, aaddr, true);
+	}
+#endif
+
 	new = ftrace_nop_replace(rec);
 	ret = ftrace_modify_code(ip, old, new, true);
 

arch/arm/kernel/head.S

@@ -23,7 +23,6 @@
 #if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_SEMIHOSTING)
 #include CONFIG_DEBUG_LL_INCLUDE
 #endif
-
 /*
  * swapper_pg_dir is the virtual address of the initial page table.
  * We place the page tables 16K below KERNEL_RAM_VADDR.  Therefore, we must
@@ -31,7 +30,7 @@
  * the least significant 16 bits to be 0x8000, but we could probably
  * relax this restriction to KERNEL_RAM_VADDR >= PAGE_OFFSET + 0x4000.
  */
-#define KERNEL_RAM_VADDR	(PAGE_OFFSET + TEXT_OFFSET)
+#define KERNEL_RAM_VADDR	(KERNEL_OFFSET + TEXT_OFFSET)
 #if (KERNEL_RAM_VADDR & 0xffff) != 0x8000
 #error KERNEL_RAM_VADDR must start at 0xXXXX8000
 #endif
@@ -48,6 +47,20 @@
 	.globl	swapper_pg_dir
 	.equ	swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE
 
+	/*
+	 * This needs to be assigned at runtime when the linker symbols are
+	 * resolved.
+	 */
+	.pushsection .data
+	.align	2
+	.globl	kernel_sec_start
+	.globl	kernel_sec_end
+kernel_sec_start:
+	.long	0
+kernel_sec_end:
+	.long	0
+	.popsection
+
 	.macro	pgtbl, rd, phys
 	add	\rd, \phys, #TEXT_OFFSET
 	sub	\rd, \rd, #PG_DIR_SIZE
@@ -230,16 +243,23 @@ __create_page_tables:
 	blo	1b
 
 	/*
-	 * Map our RAM from the start to the end of the kernel .bss section.
+	 * The main matter: map in the kernel using section mappings, and
+	 * set two variables to indicate the physical start and end of the
+	 * kernel.
 	 */
-	add	r0, r4, #PAGE_OFFSET >> (SECTION_SHIFT - PMD_ORDER)
+	add	r0, r4, #KERNEL_OFFSET >> (SECTION_SHIFT - PMD_ORDER)
 	ldr	r6, =(_end - 1)
-	orr	r3, r8, r7
+	adr_l	r5, kernel_sec_start		@ _pa(kernel_sec_start)
+	str	r8, [r5]			@ Save physical start of kernel
+	orr	r3, r8, r7			@ Add the MMU flags
 	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
 1:	str	r3, [r0], #1 << PMD_ORDER
 	add	r3, r3, #1 << SECTION_SHIFT
 	cmp	r0, r6
 	bls	1b
+	eor	r3, r3, r7			@ Remove the MMU flags
+	adr_l	r5, kernel_sec_end		@ _pa(kernel_sec_end)
+	str	r3, [r5]			@ Save physical end of kernel
 
 #ifdef CONFIG_XIP_KERNEL
 	/*

arch/arm/kernel/insn.c

@@ -3,8 +3,9 @@
 #include <linux/kernel.h>
 #include <asm/opcodes.h>
 
-static unsigned long
-__arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)
+static unsigned long __arm_gen_branch_thumb2(unsigned long pc,
+					     unsigned long addr, bool link,
+					     bool warn)
 {
 	unsigned long s, j1, j2, i1, i2, imm10, imm11;
 	unsigned long first, second;
@@ -12,7 +13,7 @@ __arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)
 
 	offset = (long)addr - (long)(pc + 4);
 	if (offset < -16777216 || offset > 16777214) {
-		WARN_ON_ONCE(1);
+		WARN_ON_ONCE(warn);
 		return 0;
 	}
 
@@ -33,8 +34,8 @@ __arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)
 	return __opcode_thumb32_compose(first, second);
 }
 
-static unsigned long
-__arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)
+static unsigned long __arm_gen_branch_arm(unsigned long pc, unsigned long addr,
+					  bool link, bool warn)
 {
 	unsigned long opcode = 0xea000000;
 	long offset;
@@ -44,7 +45,7 @@ __arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)
 
 	offset = (long)addr - (long)(pc + 8);
 	if (unlikely(offset < -33554432 || offset > 33554428)) {
-		WARN_ON_ONCE(1);
+		WARN_ON_ONCE(warn);
 		return 0;
 	}
 
@@ -54,10 +55,10 @@ __arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)
 }
 
 unsigned long
-__arm_gen_branch(unsigned long pc, unsigned long addr, bool link)
+__arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn)
 {
 	if (IS_ENABLED(CONFIG_THUMB2_KERNEL))
-		return __arm_gen_branch_thumb2(pc, addr, link);
+		return __arm_gen_branch_thumb2(pc, addr, link, warn);
 	else
-		return __arm_gen_branch_arm(pc, addr, link);
+		return __arm_gen_branch_arm(pc, addr, link, warn);
 }

arch/arm/kernel/module-plts.c

@@ -4,6 +4,7 @@
  */
 
 #include <linux/elf.h>
+#include <linux/ftrace.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/sort.h>
@@ -12,10 +13,6 @@
 #include <asm/cache.h>
 #include <asm/opcodes.h>
 
-#define PLT_ENT_STRIDE		L1_CACHE_BYTES
-#define PLT_ENT_COUNT		(PLT_ENT_STRIDE / sizeof(u32))
-#define PLT_ENT_SIZE		(sizeof(struct plt_entries) / PLT_ENT_COUNT)
-
 #ifdef CONFIG_THUMB2_KERNEL
 #define PLT_ENT_LDR		__opcode_to_mem_thumb32(0xf8dff000 | \
 							(PLT_ENT_STRIDE - 4))
@@ -24,9 +21,11 @@
 						    (PLT_ENT_STRIDE - 8))
 #endif
 
-struct plt_entries {
-	u32	ldr[PLT_ENT_COUNT];
-	u32	lit[PLT_ENT_COUNT];
+static const u32 fixed_plts[] = {
+#ifdef CONFIG_DYNAMIC_FTRACE
+	FTRACE_ADDR,
+	MCOUNT_ADDR,
+#endif
 };
 
 static bool in_init(const struct module *mod, unsigned long loc)
@@ -34,14 +33,40 @@ static bool in_init(const struct module *mod, unsigned long loc)
 	return loc - (u32)mod->init_layout.base < mod->init_layout.size;
 }
 
+static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt)
+{
+	int i;
+
+	if (!ARRAY_SIZE(fixed_plts) || pltsec->plt_count)
+		return;
+	pltsec->plt_count = ARRAY_SIZE(fixed_plts);
+
+	for (i = 0; i < ARRAY_SIZE(plt->ldr); ++i)
+		plt->ldr[i] = PLT_ENT_LDR;
+
+	BUILD_BUG_ON(sizeof(fixed_plts) > sizeof(plt->lit));
+	memcpy(plt->lit, fixed_plts, sizeof(fixed_plts));
+}
+
 u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
 {
 	struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
 							  &mod->arch.init;
+	struct plt_entries *plt;
+	int idx;
+
+	/* cache the address, ELF header is available only during module load */
+	if (!pltsec->plt_ent)
+		pltsec->plt_ent = (struct plt_entries *)pltsec->plt->sh_addr;
+	plt = pltsec->plt_ent;
 
-	struct plt_entries *plt = (struct plt_entries *)pltsec->plt->sh_addr;
-	int idx = 0;
+	prealloc_fixed(pltsec, plt);
+
+	for (idx = 0; idx < ARRAY_SIZE(fixed_plts); ++idx)
+		if (plt->lit[idx] == val)
+			return (u32)&plt->ldr[idx];
 
+	idx = 0;
 	/*
 	 * Look for an existing entry pointing to 'val'. Given that the
 	 * relocations are sorted, this will be the last entry we allocated.
@@ -189,8 +214,8 @@ static unsigned int count_plts(const Elf32_Sym *syms, Elf32_Addr base,
 int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 			      char *secstrings, struct module *mod)
 {
-	unsigned long core_plts = 0;
-	unsigned long init_plts = 0;
+	unsigned long core_plts = ARRAY_SIZE(fixed_plts);
+	unsigned long init_plts = ARRAY_SIZE(fixed_plts);
 	Elf32_Shdr *s, *sechdrs_end = sechdrs + ehdr->e_shnum;
 	Elf32_Sym *syms = NULL;
 
@@ -245,6 +270,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 	mod->arch.core.plt->sh_size = round_up(core_plts * PLT_ENT_SIZE,
 					       sizeof(struct plt_entries));
 	mod->arch.core.plt_count = 0;
+	mod->arch.core.plt_ent = NULL;
 
 	mod->arch.init.plt->sh_type = SHT_NOBITS;
 	mod->arch.init.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
@@ -252,6 +278,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 	mod->arch.init.plt->sh_size = round_up(init_plts * PLT_ENT_SIZE,
 					       sizeof(struct plt_entries));
 	mod->arch.init.plt_count = 0;
+	mod->arch.init.plt_ent = NULL;
 
 	pr_debug("%s: plt=%x, init.plt=%x\n", __func__,
 		 mod->arch.core.plt->sh_size, mod->arch.init.plt->sh_size);

arch/arm/kernel/reboot.c

@@ -18,7 +18,6 @@ typedef void (*phys_reset_t)(unsigned long, bool);
 /*
  * Function pointers to optional machine specific functions
  */
-void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
 void (*pm_power_off)(void);
 EXPORT_SYMBOL(pm_power_off);
 
@@ -138,10 +137,7 @@ void machine_restart(char *cmd)
 	local_irq_disable();
 	smp_send_stop();
 
-	if (arm_pm_restart)
-		arm_pm_restart(reboot_mode, cmd);
-	else
-		do_kernel_restart(cmd);
+	do_kernel_restart(cmd);
 
 	/* Give a grace period for failure to restart of 1s */
 	mdelay(1000);

arch/arm/kernel/setup.c

@@ -1083,6 +1083,20 @@ void __init hyp_mode_check(void)
 #endif
 }
 
+static void (*__arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
+
+static int arm_restart(struct notifier_block *nb, unsigned long action,
+		       void *data)
+{
+	__arm_pm_restart(action, data);
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block arm_restart_nb = {
+	.notifier_call = arm_restart,
+	.priority = 128,
+};
+
 void __init setup_arch(char **cmdline_p)
 {
 	const struct machine_desc *mdesc = NULL;
@@ -1151,8 +1165,10 @@ void __init setup_arch(char **cmdline_p)
 	kasan_init();
 	request_standard_resources(mdesc);
 
-	if (mdesc->restart)
-		arm_pm_restart = mdesc->restart;
+	if (mdesc->restart) {
+		__arm_pm_restart = mdesc->restart;
+		register_restart_handler(&arm_restart_nb);
+	}
 
 	unflatten_device_tree();
 

arch/arm/kernel/vmlinux.lds.S

@@ -47,7 +47,7 @@ SECTIONS
 #endif
 	}
 
-	. = PAGE_OFFSET + TEXT_OFFSET;
+	. = KERNEL_OFFSET + TEXT_OFFSET;
 	.head.text : {
 		_text = .;
 		HEAD_TEXT

arch/arm/mm/Kconfig

@@ -601,8 +601,6 @@ config CPU_TLB_V6
 config CPU_TLB_V7
 	bool
 
-config VERIFY_PERMISSION_FAULT
-	bool
 endif
 
 config CPU_HAS_ASID

arch/arm/mm/abort-ev7.S

@@ -17,31 +17,5 @@ ENTRY(v7_early_abort)
 	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
 	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
 	uaccess_disable ip			@ disable userspace access
-
-	/*
-	 * V6 code adjusts the returned DFSR.
-	 * New designs should not need to patch up faults.
-	 */
-
-#if defined(CONFIG_VERIFY_PERMISSION_FAULT)
-	/*
-	 * Detect erroneous permission failures and fix
-	 */
-	ldr	r3, =0x40d			@ On permission fault
-	and	r3, r1, r3
-	cmp	r3, #0x0d
-	bne	do_DataAbort
-
-	mcr	p15, 0, r0, c7, c8, 0   	@ Retranslate FAR
-	isb
-	mrc	p15, 0, ip, c7, c4, 0   	@ Read the PAR
-	and	r3, ip, #0x7b   		@ On translation fault
-	cmp	r3, #0x0b
-	bne	do_DataAbort
-	bic	r1, r1, #0xf			@ Fix up FSR FS[5:0]
-	and	ip, ip, #0x7e
-	orr	r1, r1, ip, LSR #1
-#endif
-
 	b	do_DataAbort
 ENDPROC(v7_early_abort)

arch/arm/mm/mmu.c

@@ -1121,31 +1121,32 @@ void __init debug_ll_io_init(void)
 }
 #endif
 
-static void * __initdata vmalloc_min =
-	(void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
+static unsigned long __initdata vmalloc_size = 240 * SZ_1M;
 
 /*
  * vmalloc=size forces the vmalloc area to be exactly 'size'
  * bytes. This can be used to increase (or decrease) the vmalloc
- * area - the default is 240m.
+ * area - the default is 240MiB.
  */
 static int __init early_vmalloc(char *arg)
 {
 	unsigned long vmalloc_reserve = memparse(arg, NULL);
+	unsigned long vmalloc_max;
 
 	if (vmalloc_reserve < SZ_16M) {
 		vmalloc_reserve = SZ_16M;
-		pr_warn("vmalloc area too small, limiting to %luMB\n",
+		pr_warn("vmalloc area is too small, limiting to %luMiB\n",
 			vmalloc_reserve >> 20);
 	}
 
-	if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
-		vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
-		pr_warn("vmalloc area is too big, limiting to %luMB\n",
+	vmalloc_max = VMALLOC_END - (PAGE_OFFSET + SZ_32M + VMALLOC_OFFSET);
+	if (vmalloc_reserve > vmalloc_max) {
+		vmalloc_reserve = vmalloc_max;
+		pr_warn("vmalloc area is too big, limiting to %luMiB\n",
 			vmalloc_reserve >> 20);
 	}
 
-	vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
+	vmalloc_size = vmalloc_reserve;
 	return 0;
 }
 early_param("vmalloc", early_vmalloc);
@@ -1165,7 +1166,8 @@ void __init adjust_lowmem_bounds(void)
 	 * and may itself be outside the valid range for which phys_addr_t
 	 * and therefore __pa() is defined.
 	 */
-	vmalloc_limit = (u64)(uintptr_t)vmalloc_min - PAGE_OFFSET + PHYS_OFFSET;
+	vmalloc_limit = (u64)VMALLOC_END - vmalloc_size - VMALLOC_OFFSET -
+			PAGE_OFFSET + PHYS_OFFSET;
 
 	/*
 	 * The first usable region must be PMD aligned. Mark its start
@@ -1246,7 +1248,7 @@ void __init adjust_lowmem_bounds(void)
 	memblock_set_current_limit(memblock_limit);
 }
 
-static inline void prepare_page_table(void)
+static __init void prepare_page_table(void)
 {
 	unsigned long addr;
 	phys_addr_t end;
@@ -1457,8 +1459,6 @@ static void __init kmap_init(void)
 
 static void __init map_lowmem(void)
 {
-	phys_addr_t kernel_x_start = round_down(__pa(KERNEL_START), SECTION_SIZE);
-	phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
 	phys_addr_t start, end;
 	u64 i;
 
@@ -1466,55 +1466,126 @@ static void __init map_lowmem(void)
 	for_each_mem_range(i, &start, &end) {
 		struct map_desc map;
 
+		pr_debug("map lowmem start: 0x%08llx, end: 0x%08llx\n",
+			 (long long)start, (long long)end);
 		if (end > arm_lowmem_limit)
 			end = arm_lowmem_limit;
 		if (start >= end)
 			break;
 
-		if (end < kernel_x_start) {
-			map.pfn = __phys_to_pfn(start);
-			map.virtual = __phys_to_virt(start);
-			map.length = end - start;
-			map.type = MT_MEMORY_RWX;
+		/*
+		 * If our kernel image is in the VMALLOC area we need to remove
+		 * the kernel physical memory from lowmem since the kernel will
+		 * be mapped separately.
+		 *
+		 * The kernel will typically be at the very start of lowmem,
+		 * but any placement relative to memory ranges is possible.
+		 *
+		 * If the memblock contains the kernel, we have to chisel out
+		 * the kernel memory from it and map each part separately. We
+		 * get 6 different theoretical cases:
+		 *
+		 *                            +--------+ +--------+
+		 *  +-- start --+  +--------+ | Kernel | | Kernel |
+		 *  |           |  | Kernel | | case 2 | | case 5 |
+		 *  |           |  | case 1 | +--------+ |        | +--------+
+		 *  |  Memory   |  +--------+            |        | | Kernel |
+		 *  |  range    |  +--------+            |        | | case 6 |
+		 *  |           |  | Kernel | +--------+ |        | +--------+
+		 *  |           |  | case 3 | | Kernel | |        |
+		 *  +-- end ----+  +--------+ | case 4 | |        |
+		 *                            +--------+ +--------+
+		 */
 
-			create_mapping(&map);
-		} else if (start >= kernel_x_end) {
-			map.pfn = __phys_to_pfn(start);
-			map.virtual = __phys_to_virt(start);
-			map.length = end - start;
-			map.type = MT_MEMORY_RW;
+		/* Case 5: kernel covers range, don't map anything, should be rare */
+		if ((start > kernel_sec_start) && (end < kernel_sec_end))
+			break;
 
-			create_mapping(&map);
-		} else {
-			/* This better cover the entire kernel */
-			if (start < kernel_x_start) {
+		/* Cases where the kernel is starting inside the range */
+		if ((kernel_sec_start >= start) && (kernel_sec_start <= end)) {
+			/* Case 6: kernel is embedded in the range, we need two mappings */
+			if ((start < kernel_sec_start) && (end > kernel_sec_end)) {
+				/* Map memory below the kernel */
 				map.pfn = __phys_to_pfn(start);
 				map.virtual = __phys_to_virt(start);
-				map.length = kernel_x_start - start;
+				map.length = kernel_sec_start - start;
 				map.type = MT_MEMORY_RW;
-
 				create_mapping(&map);
-			}
-
-			map.pfn = __phys_to_pfn(kernel_x_start);
-			map.virtual = __phys_to_virt(kernel_x_start);
-			map.length = kernel_x_end - kernel_x_start;
-			map.type = MT_MEMORY_RWX;
-
-			create_mapping(&map);
-
-			if (kernel_x_end < end) {
-				map.pfn = __phys_to_pfn(kernel_x_end);
-				map.virtual = __phys_to_virt(kernel_x_end);
-				map.length = end - kernel_x_end;
+				/* Map memory above the kernel */
+				map.pfn = __phys_to_pfn(kernel_sec_end);
+				map.virtual = __phys_to_virt(kernel_sec_end);
+				map.length = end - kernel_sec_end;
 				map.type = MT_MEMORY_RW;
-
 				create_mapping(&map);
+				break;
 			}
+			/* Case 1: kernel and range start at the same address, should be common */
+			if (kernel_sec_start == start)
+				start = kernel_sec_end;
+			/* Case 3: kernel and range end at the same address, should be rare */
+			if (kernel_sec_end == end)
+				end = kernel_sec_start;
+		} else if ((kernel_sec_start < start) && (kernel_sec_end > start) && (kernel_sec_end < end)) {
+			/* Case 2: kernel ends inside range, starts below it */
+			start = kernel_sec_end;
+		} else if ((kernel_sec_start > start) && (kernel_sec_start < end) && (kernel_sec_end > end)) {
+			/* Case 4: kernel starts inside range, ends above it */
+			end = kernel_sec_start;
 		}
+		map.pfn = __phys_to_pfn(start);
+		map.virtual = __phys_to_virt(start);
+		map.length = end - start;
+		map.type = MT_MEMORY_RW;
+		create_mapping(&map);
 	}
 }
 
+static void __init map_kernel(void)
+{
+	/*
+	 * We use the well known kernel section start and end and split the area in the
+	 * middle like this:
+	 *  .                .
+	 *  | RW memory      |
+	 *  +----------------+ kernel_x_start
+	 *  | Executable     |
+	 *  | kernel memory  |
+	 *  +----------------+ kernel_x_end / kernel_nx_start
+	 *  | Non-executable |
+	 *  | kernel memory  |
+	 *  +----------------+ kernel_nx_end
+	 *  | RW memory      |
+	 *  .                .
+	 *
+	 * Notice that we are dealing with section sized mappings here so all of this
+	 * will be bumped to the closest section boundary. This means that some of the
+	 * non-executable part of the kernel memory is actually mapped as executable.
+	 * This will only persist until we turn on proper memory management later on
+	 * and we remap the whole kernel with page granularity.
+	 */
+	phys_addr_t kernel_x_start = kernel_sec_start;
+	phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
+	phys_addr_t kernel_nx_start = kernel_x_end;
+	phys_addr_t kernel_nx_end = kernel_sec_end;
+	struct map_desc map;
+
+	map.pfn = __phys_to_pfn(kernel_x_start);
+	map.virtual = __phys_to_virt(kernel_x_start);
+	map.length = kernel_x_end - kernel_x_start;
+	map.type = MT_MEMORY_RWX;
+	create_mapping(&map);
+
+	/* If the nx part is small it may end up covered by the tail of the RWX section */
+	if (kernel_x_end == kernel_nx_end)
+		return;
+
+	map.pfn = __phys_to_pfn(kernel_nx_start);
+	map.virtual = __phys_to_virt(kernel_nx_start);
+	map.length = kernel_nx_end - kernel_nx_start;
+	map.type = MT_MEMORY_RW;
+	create_mapping(&map);
+}
+
 #ifdef CONFIG_ARM_PV_FIXUP
 typedef void pgtables_remap(long long offset, unsigned long pgd);
 pgtables_remap lpae_pgtables_remap_asm;
@@ -1645,9 +1716,18 @@ void __init paging_init(const struct machine_desc *mdesc)
 {
 	void *zero_page;
 
+	pr_debug("physical kernel sections: 0x%08x-0x%08x\n",
+		 kernel_sec_start, kernel_sec_end);
+
 	prepare_page_table();
 	map_lowmem();
 	memblock_set_current_limit(arm_lowmem_limit);
+	pr_debug("lowmem limit is %08llx\n", (long long)arm_lowmem_limit);
+	/*
+	 * After this point early_alloc(), i.e. the memblock allocator, can
+	 * be used
+	 */
+	map_kernel();
 	dma_contiguous_remap();
 	early_fixmap_shutdown();
 	devicemaps_init(mdesc);

arch/arm/probes/kprobes/test-thumb.c

@@ -441,21 +441,21 @@ void kprobe_thumb32_test_cases(void)
 		"3:	mvn	r0, r0	\n\t"
 		"2:	nop		\n\t")
 
-	TEST_RX("tbh	[pc, r",7, (9f-(1f+4))>>1,"]",
+	TEST_RX("tbh	[pc, r",7, (9f-(1f+4))>>1,", lsl #1]",
 		"9:			\n\t"
 		".short	(2f-1b-4)>>1	\n\t"
 		".short	(3f-1b-4)>>1	\n\t"
 		"3:	mvn	r0, r0	\n\t"
 		"2:	nop		\n\t")
 
-	TEST_RX("tbh	[pc, r",12, ((9f-(1f+4))>>1)+1,"]",
+	TEST_RX("tbh	[pc, r",12, ((9f-(1f+4))>>1)+1,", lsl #1]",
 		"9:			\n\t"
 		".short	(2f-1b-4)>>1	\n\t"
 		".short	(3f-1b-4)>>1	\n\t"
 		"3:	mvn	r0, r0	\n\t"
 		"2:	nop		\n\t")
 
-	TEST_RRX("tbh	[r",1,9f, ", r",14,1,"]",
+	TEST_RRX("tbh	[r",1,9f, ", r",14,1,", lsl #1]",
 		"9:			\n\t"
 		".short	(2f-1b-4)>>1	\n\t"
 		".short	(3f-1b-4)>>1	\n\t"
@@ -468,10 +468,10 @@ void kprobe_thumb32_test_cases(void)
 
 	TEST_UNSUPPORTED("strexb	r0, r1, [r2]")
 	TEST_UNSUPPORTED("strexh	r0, r1, [r2]")
-	TEST_UNSUPPORTED("strexd	r0, r1, [r2]")
+	TEST_UNSUPPORTED("strexd	r0, r1, r2, [r2]")
 	TEST_UNSUPPORTED("ldrexb	r0, [r1]")
 	TEST_UNSUPPORTED("ldrexh	r0, [r1]")
-	TEST_UNSUPPORTED("ldrexd	r0, [r1]")
+	TEST_UNSUPPORTED("ldrexd	r0, r1, [r1]")
 
 	TEST_GROUP("Data-processing (shifted register) and (modified immediate)")
 

arch/arm/tools/Makefile

@@ -33,39 +33,26 @@ _dummy := $(shell [ -d '$(kapi)' ] || mkdir -p '$(kapi)') \
           $(shell [ -d '$(uapi)' ] || mkdir -p '$(uapi)')
 
 quiet_cmd_gen_mach = GEN     $@
-      cmd_gen_mach = mkdir -p $(dir $@) && \
-		     $(AWK) -f $(filter-out $(PHONY),$^) > $@
+      cmd_gen_mach = $(AWK) -f $(real-prereqs) > $@
 
 $(kapi)/mach-types.h: $(src)/gen-mach-types $(src)/mach-types FORCE
 	$(call if_changed,gen_mach)
 
 quiet_cmd_syshdr = SYSHDR  $@
-      cmd_syshdr = $(CONFIG_SHELL) $(syshdr) --abis $(abis) \
+      cmd_syshdr = $(CONFIG_SHELL) $(syshdr) --abis common,$* \
 		   --offset __NR_SYSCALL_BASE $< $@
 
 quiet_cmd_systbl = SYSTBL  $@
-      cmd_systbl = $(CONFIG_SHELL) $(systbl) --abis $(abis) $< $@
+      cmd_systbl = $(CONFIG_SHELL) $(systbl) --abis common,$* $< $@
 
 quiet_cmd_sysnr  = SYSNR   $@
-      cmd_sysnr  = $(CONFIG_SHELL) '$(sysnr)' '$<' '$@' \
-		   '$(syshdr_abi_$(basetarget))'
+      cmd_sysnr  = $(CONFIG_SHELL) $(sysnr) $< $@
 
-$(uapi)/unistd-oabi.h: abis := common,oabi
-$(uapi)/unistd-oabi.h: $(syscall) $(syshdr) FORCE
+$(uapi)/unistd-%.h: $(syscall) $(syshdr) FORCE
 	$(call if_changed,syshdr)
 
-$(uapi)/unistd-eabi.h: abis := common,eabi
-$(uapi)/unistd-eabi.h: $(syscall) $(syshdr) FORCE
-	$(call if_changed,syshdr)
-
-sysnr_abi_unistd-nr := common,oabi,eabi,compat
 $(kapi)/unistd-nr.h: $(syscall) $(sysnr) FORCE
 	$(call if_changed,sysnr)
 
-$(gen)/calls-oabi.S: abis := common,oabi
-$(gen)/calls-oabi.S: $(syscall) $(systbl) FORCE
-	$(call if_changed,systbl)
-
-$(gen)/calls-eabi.S: abis := common,eabi
-$(gen)/calls-eabi.S: $(syscall) $(systbl) FORCE
+$(gen)/calls-%.S: $(syscall) $(systbl) FORCE
 	$(call if_changed,systbl)

arch/arm/tools/syscallnr.sh

@@ -2,14 +2,13 @@
 # SPDX-License-Identifier: GPL-2.0
 in="$1"
 out="$2"
-my_abis=`echo "($3)" | tr ',' '|'`
 align=1
 
 fileguard=_ASM_ARM_`basename "$out" | sed \
     -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \
     -e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g'`
 
-grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | tail -n1 | (
+grep -E "^[0-9A-Fa-fXx]+[[:space:]]+" "$in" | sort -n | tail -n1 | (
     echo "#ifndef ${fileguard}
 #define ${fileguard} 1
 

arch/arm/xen/enlighten.c

@@ -29,6 +29,7 @@
 #include <linux/cpu.h>
 #include <linux/console.h>
 #include <linux/pvclock_gtod.h>
+#include <linux/reboot.h>
 #include <linux/time64.h>
 #include <linux/timekeeping.h>
 #include <linux/timekeeper_internal.h>
@@ -181,11 +182,18 @@ void xen_reboot(int reason)
 	BUG_ON(rc);
 }
 
-static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
+static int xen_restart(struct notifier_block *nb, unsigned long action,
+		       void *data)
 {
 	xen_reboot(SHUTDOWN_reboot);
+
+	return NOTIFY_DONE;
 }
 
+static struct notifier_block xen_restart_nb = {
+	.notifier_call = xen_restart,
+	.priority = 192,
+};
 
 static void xen_power_off(void)
 {
@@ -404,7 +412,7 @@ static int __init xen_pm_init(void)
 		return -ENODEV;
 
 	pm_power_off = xen_power_off;
-	arm_pm_restart = xen_restart;
+	register_restart_handler(&xen_restart_nb);
 	if (!xen_initial_domain()) {
 		struct timespec64 ts;
 		xen_read_wallclock(&ts);

arch/arm64/include/asm/system_misc.h

@@ -32,8 +32,6 @@ void hook_debug_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
 struct mm_struct;
 extern void __show_regs(struct pt_regs *);
 
-extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
-
 #endif	/* __ASSEMBLY__ */
 
 #endif	/* __ASM_SYSTEM_MISC_H */

arch/arm64/kernel/process.c

@@ -70,8 +70,6 @@ EXPORT_SYMBOL(__stack_chk_guard);
 void (*pm_power_off)(void);
 EXPORT_SYMBOL_GPL(pm_power_off);
 
-void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
-
 #ifdef CONFIG_HOTPLUG_CPU
 void arch_cpu_idle_dead(void)
 {
@@ -142,10 +140,7 @@ void machine_restart(char *cmd)
 		efi_reboot(reboot_mode, NULL);
 
 	/* Now call the architecture specific reboot code. */
-	if (arm_pm_restart)
-		arm_pm_restart(reboot_mode, cmd);
-	else
-		do_kernel_restart(cmd);
+	do_kernel_restart(cmd);
 
 	/*
 	 * Whoops - the architecture was unable to reboot.

drivers/firmware/psci/psci.c

@@ -296,7 +296,8 @@ static int get_set_conduit_method(struct device_node *np)
 	return 0;
 }
 
-static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
+static int psci_sys_reset(struct notifier_block *nb, unsigned long action,
+			  void *data)
 {
 	if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
 	    psci_system_reset2_supported) {
@@ -309,8 +310,15 @@ static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
 	} else {
 		invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
 	}
+
+	return NOTIFY_DONE;
 }
 
+static struct notifier_block psci_sys_reset_nb = {
+	.notifier_call = psci_sys_reset,
+	.priority = 129,
+};
+
 static void psci_sys_poweroff(void)
 {
 	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
@@ -477,7 +485,7 @@ static void __init psci_0_2_set_functions(void)
 		.migrate_info_type = psci_migrate_info_type,
 	};
 
-	arm_pm_restart = psci_sys_reset;
+	register_restart_handler(&psci_sys_reset_nb);
 
 	pm_power_off = psci_sys_poweroff;
 }