1 files changed, 130 insertions, 117 deletions

diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index c6dec5fc20a..81ef686a91c 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -30,15 +30,17 @@
 #include <linux/uaccess.h>
 #include <linux/random.h>
 #include <linux/hw_breakpoint.h>
-#include <linux/cpuidle.h>
 #include <linux/leds.h>
+#include <linux/reboot.h>
 
 #include <asm/cacheflush.h>
 #include <asm/idmap.h>
 #include <asm/processor.h>
 #include <asm/thread_notify.h>
 #include <asm/stacktrace.h>
+#include <asm/system_misc.h>
 #include <asm/mach/time.h>
+#include <asm/tls.h>
 
 #ifdef CONFIG_CC_STACKPROTECTOR
 #include <linux/stackprotector.h>
@@ -46,49 +48,17 @@ unsigned long __stack_chk_guard __read_mostly;
 EXPORT_SYMBOL(__stack_chk_guard);
 #endif
 
-static const char *processor_modes[] = {
+static const char *processor_modes[] __maybe_unused = {
   "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
   "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
   "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
   "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
 };
 
-static const char *isa_modes[] = {
+static const char *isa_modes[] __maybe_unused = {
   "ARM" , "Thumb" , "Jazelle", "ThumbEE"
 };
 
-static volatile int hlt_counter;
-
-void disable_hlt(void)
-{
-	hlt_counter++;
-}
-
-EXPORT_SYMBOL(disable_hlt);
-
-void enable_hlt(void)
-{
-	hlt_counter--;
-	BUG_ON(hlt_counter < 0);
-}
-
-EXPORT_SYMBOL(enable_hlt);
-
-static int __init nohlt_setup(char *__unused)
-{
-	hlt_counter = 1;
-	return 1;
-}
-
-static int __init hlt_setup(char *__unused)
-{
-	hlt_counter = 0;
-	return 1;
-}
-
-__setup("nohlt", nohlt_setup);
-__setup("hlt", hlt_setup);
-
 extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
 typedef void (*phys_reset_t)(unsigned long);
 
@@ -130,7 +100,7 @@ void soft_restart(unsigned long addr)
 	u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
 
 	/* Disable interrupts first */
-	local_irq_disable();
+	raw_local_irq_disable();
 	local_fiq_disable();
 
 	/* Disable the L2 if we're the last man standing. */
@@ -144,7 +114,7 @@ void soft_restart(unsigned long addr)
 	BUG();
 }
 
-static void null_restart(char mode, const char *cmd)
+static void null_restart(enum reboot_mode reboot_mode, const char *cmd)
 {
 }
 
@@ -154,7 +124,7 @@ static void null_restart(char mode, const char *cmd)
 void (*pm_power_off)(void);
 EXPORT_SYMBOL(pm_power_off);
 
-void (*arm_pm_restart)(char str, const char *cmd) = null_restart;
+void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd) = null_restart;
 EXPORT_SYMBOL_GPL(arm_pm_restart);
 
 /*
@@ -163,7 +133,11 @@ EXPORT_SYMBOL_GPL(arm_pm_restart);
 
 void (*arm_pm_idle)(void);
 
-static void default_idle(void)
+/*
+ * Called from the core idle loop.
+ */
+
+void arch_cpu_idle(void)
 {
 	if (arm_pm_idle)
 		arm_pm_idle();
@@ -172,95 +146,89 @@ static void default_idle(void)
 	local_irq_enable();
 }
 
-void (*pm_idle)(void) = default_idle;
-EXPORT_SYMBOL(pm_idle);
-
-/*
- * The idle thread, has rather strange semantics for calling pm_idle,
- * but this is what x86 does and we need to do the same, so that
- * things like cpuidle get called in the same way.  The only difference
- * is that we always respect 'hlt_counter' to prevent low power idle.
- */
-void cpu_idle(void)
+void arch_cpu_idle_prepare(void)
 {
 	local_fiq_enable();
+}
 
-	/* endless idle loop with no priority at all */
-	while (1) {
-		tick_nohz_idle_enter();
-		rcu_idle_enter();
-		ledtrig_cpu(CPU_LED_IDLE_START);
-		while (!need_resched()) {
-#ifdef CONFIG_HOTPLUG_CPU
-			if (cpu_is_offline(smp_processor_id()))
-				cpu_die();
-#endif
-
-			/*
-			 * We need to disable interrupts here
-			 * to ensure we don't miss a wakeup call.
-			 */
-			local_irq_disable();
+void arch_cpu_idle_enter(void)
+{
+	ledtrig_cpu(CPU_LED_IDLE_START);
 #ifdef CONFIG_PL310_ERRATA_769419
-			wmb();
+	wmb();
 #endif
-			if (hlt_counter) {
-				local_irq_enable();
-				cpu_relax();
-			} else if (!need_resched()) {
-				stop_critical_timings();
-				if (cpuidle_idle_call())
-					pm_idle();
-				start_critical_timings();
-				/*
-				 * pm_idle functions must always
-				 * return with IRQs enabled.
-				 */
-				WARN_ON(irqs_disabled());
-			} else
-				local_irq_enable();
-		}
-		ledtrig_cpu(CPU_LED_IDLE_END);
-		rcu_idle_exit();
-		tick_nohz_idle_exit();
-		schedule_preempt_disabled();
-	}
 }
 
-static char reboot_mode = 'h';
-
-int __init reboot_setup(char *str)
+void arch_cpu_idle_exit(void)
 {
-	reboot_mode = str[0];
-	return 1;
+	ledtrig_cpu(CPU_LED_IDLE_END);
 }
 
-__setup("reboot=", reboot_setup);
+#ifdef CONFIG_HOTPLUG_CPU
+void arch_cpu_idle_dead(void)
+{
+	cpu_die();
+}
+#endif
 
+/*
+ * Called by kexec, immediately prior to machine_kexec().
+ *
+ * This must completely disable all secondary CPUs; simply causing those CPUs
+ * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
+ * kexec'd kernel to use any and all RAM as it sees fit, without having to
+ * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
+ * functionality embodied in disable_nonboot_cpus() to achieve this.
+ */
 void machine_shutdown(void)
 {
-#ifdef CONFIG_SMP
-	smp_send_stop();
-#endif
+	disable_nonboot_cpus();
 }
 
+/*
+ * Halting simply requires that the secondary CPUs stop performing any
+ * activity (executing tasks, handling interrupts). smp_send_stop()
+ * achieves this.
+ */
 void machine_halt(void)
 {
-	machine_shutdown();
+	local_irq_disable();
+	smp_send_stop();
+
 	local_irq_disable();
 	while (1);
 }
 
+/*
+ * Power-off simply requires that the secondary CPUs stop performing any
+ * activity (executing tasks, handling interrupts). smp_send_stop()
+ * achieves this. When the system power is turned off, it will take all CPUs
+ * with it.
+ */
 void machine_power_off(void)
 {
-	machine_shutdown();
+	local_irq_disable();
+	smp_send_stop();
+
 	if (pm_power_off)
 		pm_power_off();
 }
 
+/*
+ * Restart requires that the secondary CPUs stop performing any activity
+ * while the primary CPU resets the system. Systems with a single CPU can
+ * use soft_restart() as their machine descriptor's .restart hook, since that
+ * will cause the only available CPU to reset. Systems with multiple CPUs must
+ * provide a HW restart implementation, to ensure that all CPUs reset at once.
+ * This is required so that any code running after reset on the primary CPU
+ * doesn't have to co-ordinate with other CPUs to ensure they aren't still
+ * executing pre-reset code, and using RAM that the primary CPU's code wishes
+ * to use. Implementing such co-ordination would be essentially impossible.
+ */
 void machine_restart(char *cmd)
 {
-	machine_shutdown();
+	local_irq_disable();
+	smp_send_stop();
 
 	arm_pm_restart(reboot_mode, cmd);
 
@@ -278,11 +246,8 @@ void __show_regs(struct pt_regs *regs)
 	unsigned long flags;
 	char buf[64];
 
-	printk("CPU: %d    %s  (%s %.*s)\n",
-		raw_smp_processor_id(), print_tainted(),
-		init_utsname()->release,
-		(int)strcspn(init_utsname()->version, " "),
-		init_utsname()->version);
+	show_regs_print_info(KERN_DEFAULT);
+
 	print_symbol("PC is at %s\n", instruction_pointer(regs));
 	print_symbol("LR is at %s\n", regs->ARM_lr);
 	printk("pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
@@ -306,12 +271,17 @@ void __show_regs(struct pt_regs *regs)
 	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
 	buf[4] = '\0';
 
+#ifndef CONFIG_CPU_V7M
 	printk("Flags: %s  IRQs o%s  FIQs o%s  Mode %s  ISA %s  Segment %s\n",
 		buf, interrupts_enabled(regs) ? "n" : "ff",
 		fast_interrupts_enabled(regs) ? "n" : "ff",
 		processor_modes[processor_mode(regs)],
 		isa_modes[isa_mode(regs)],
 		get_fs() == get_ds() ? "kernel" : "user");
+#else
+	printk("xPSR: %08lx\n", regs->ARM_cpsr);
+#endif
+
 #ifdef CONFIG_CPU_CP15
 	{
 		unsigned int ctrl;
@@ -337,7 +307,6 @@ void __show_regs(struct pt_regs *regs)
 void show_regs(struct pt_regs * regs)
 {
 	printk("\n");
-	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
 	__show_regs(regs);
 	dump_stack();
 }
@@ -400,7 +369,8 @@ copy_thread(unsigned long clone_flags, unsigned long stack_start,
 	clear_ptrace_hw_breakpoint(p);
 
 	if (clone_flags & CLONE_SETTLS)
-		thread->tp_value = childregs->ARM_r3;
+		thread->tp_value[0] = childregs->ARM_r3;
+	thread->tp_value[1] = get_tpuser();
 
 	thread_notify(THREAD_NOTIFY_COPY, thread);
 
@@ -434,6 +404,7 @@ EXPORT_SYMBOL(dump_fpu);
 unsigned long get_wchan(struct task_struct *p)
 {
 	struct stackframe frame;
+	unsigned long stack_page;
 	int count = 0;
 	if (!p || p == current || p->state == TASK_RUNNING)
 		return 0;
@@ -442,9 +413,11 @@ unsigned long get_wchan(struct task_struct *p)
 	frame.sp = thread_saved_sp(p);
 	frame.lr = 0;			/* recovered from the stack */
 	frame.pc = thread_saved_pc(p);
+	stack_page = (unsigned long)task_stack_page(p);
 	do {
-		int ret = unwind_frame(&frame);
-		if (ret < 0)
+		if (frame.sp < stack_page ||
+		    frame.sp >= stack_page + THREAD_SIZE ||
+		    unwind_frame(&frame) < 0)
 			return 0;
 		if (!in_sched_functions(frame.pc))
 			return frame.pc;
@@ -459,20 +432,21 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
 }
 
 #ifdef CONFIG_MMU
+#ifdef CONFIG_KUSER_HELPERS
 /*
  * The vectors page is always readable from user space for the
- * atomic helpers and the signal restart code. Insert it into the
- * gate_vma so that it is visible through ptrace and /proc/<pid>/mem.
+ * atomic helpers. Insert it into the gate_vma so that it is visible
+ * through ptrace and /proc/<pid>/mem.
  */
-static struct vm_area_struct gate_vma;
+static struct vm_area_struct gate_vma = {
+	.vm_start	= 0xffff0000,
+	.vm_end		= 0xffff0000 + PAGE_SIZE,
+	.vm_flags	= VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC,
+};
 
 static int __init gate_vma_init(void)
 {
-	gate_vma.vm_start	= 0xffff0000;
-	gate_vma.vm_end		= 0xffff0000 + PAGE_SIZE;
-	gate_vma.vm_page_prot	= PAGE_READONLY_EXEC;
-	gate_vma.vm_flags	= VM_READ | VM_EXEC |
-				  VM_MAYREAD | VM_MAYEXEC;
+	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
 	return 0;
 }
 arch_initcall(gate_vma_init);
@@ -491,9 +465,48 @@ int in_gate_area_no_mm(unsigned long addr)
 {
 	return in_gate_area(NULL, addr);
 }
+#define is_gate_vma(vma)	((vma) == &gate_vma)
+#else
+#define is_gate_vma(vma)	0
+#endif
 
 const char *arch_vma_name(struct vm_area_struct *vma)
 {
-	return (vma == &gate_vma) ? "[vectors]" : NULL;
+	return is_gate_vma(vma) ? "[vectors]" :
+		(vma->vm_mm && vma->vm_start == vma->vm_mm->context.sigpage) ?
+		 "[sigpage]" : NULL;
+}
+
+static struct page *signal_page;
+extern struct page *get_signal_page(void);
+
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	struct mm_struct *mm = current->mm;
+	unsigned long addr;
+	int ret;
+
+	if (!signal_page)
+		signal_page = get_signal_page();
+	if (!signal_page)
+		return -ENOMEM;
+
+	down_write(&mm->mmap_sem);
+	addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
+	if (IS_ERR_VALUE(addr)) {
+		ret = addr;
+		goto up_fail;
+	}
+
+	ret = install_special_mapping(mm, addr, PAGE_SIZE,
+		VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
+		&signal_page);
+
+	if (ret == 0)
+		mm->context.sigpage = addr;
+
+ up_fail:
+	up_write(&mm->mmap_sem);
+	return ret;
 }
 #endif