1 files changed, 177 insertions, 154 deletions

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 6309b275cb9..137a86171c3 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -3,7 +3,7 @@
  *
  *  Pentium III FXSR, SSE support
  *	Gareth Hughes <gareth@valinux.com>, May 2000
- * 
+ *
  *  X86-64 port
  *	Andi Kleen.
  *
@@ -19,19 +19,19 @@
 #include <linux/cpu.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
+#include <linux/fs.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
-#include <linux/fs.h>
 #include <linux/elfcore.h>
 #include <linux/smp.h>
 #include <linux/slab.h>
 #include <linux/user.h>
-#include <linux/module.h>
 #include <linux/a.out.h>
 #include <linux/interrupt.h>
+#include <linux/utsname.h>
 #include <linux/delay.h>
+#include <linux/module.h>
 #include <linux/ptrace.h>
-#include <linux/utsname.h>
 #include <linux/random.h>
 #include <linux/notifier.h>
 #include <linux/kprobes.h>
@@ -72,13 +72,6 @@ void idle_notifier_register(struct notifier_block *n)
 {
 	atomic_notifier_chain_register(&idle_notifier, n);
 }
-EXPORT_SYMBOL_GPL(idle_notifier_register);
-
-void idle_notifier_unregister(struct notifier_block *n)
-{
-	atomic_notifier_chain_unregister(&idle_notifier, n);
-}
-EXPORT_SYMBOL(idle_notifier_unregister);
 
 void enter_idle(void)
 {
@@ -106,7 +99,7 @@ void exit_idle(void)
  * We use this if we don't have any better
  * idle routine..
  */
-static void default_idle(void)
+void default_idle(void)
 {
 	current_thread_info()->status &= ~TS_POLLING;
 	/*
@@ -116,11 +109,18 @@ static void default_idle(void)
 	smp_mb();
 	local_irq_disable();
 	if (!need_resched()) {
-		/* Enables interrupts one instruction before HLT.
-		   x86 special cases this so there is no race. */
-		safe_halt();
-	} else
-		local_irq_enable();
+		ktime_t t0, t1;
+		u64 t0n, t1n;
+
+		t0 = ktime_get();
+		t0n = ktime_to_ns(t0);
+		safe_halt();	/* enables interrupts racelessly */
+		local_irq_disable();
+		t1 = ktime_get();
+		t1n = ktime_to_ns(t1);
+		sched_clock_idle_wakeup_event(t1n - t0n);
+	}
+	local_irq_enable();
 	current_thread_info()->status |= TS_POLLING;
 }
 
@@ -129,43 +129,12 @@ static void default_idle(void)
  * to poll the ->need_resched flag instead of waiting for the
  * cross-CPU IPI to arrive. Use this option with caution.
  */
-static void poll_idle (void)
+static void poll_idle(void)
 {
 	local_irq_enable();
 	cpu_relax();
 }
 
-void cpu_idle_wait(void)
-{
-	unsigned int cpu, this_cpu = get_cpu();
-	cpumask_t map, tmp = current->cpus_allowed;
-
-	set_cpus_allowed(current, cpumask_of_cpu(this_cpu));
-	put_cpu();
-
-	cpus_clear(map);
-	for_each_online_cpu(cpu) {
-		per_cpu(cpu_idle_state, cpu) = 1;
-		cpu_set(cpu, map);
-	}
-
-	__get_cpu_var(cpu_idle_state) = 0;
-
-	wmb();
-	do {
-		ssleep(1);
-		for_each_online_cpu(cpu) {
-			if (cpu_isset(cpu, map) &&
-					!per_cpu(cpu_idle_state, cpu))
-				cpu_clear(cpu, map);
-		}
-		cpus_and(map, map, cpu_online_map);
-	} while (!cpus_empty(map));
-
-	set_cpus_allowed(current, tmp);
-}
-EXPORT_SYMBOL_GPL(cpu_idle_wait);
-
 #ifdef CONFIG_HOTPLUG_CPU
 DECLARE_PER_CPU(int, cpu_state);
 
@@ -196,19 +165,18 @@ static inline void play_dead(void)
  * low exit latency (ie sit in a loop waiting for
  * somebody to say that they'd like to reschedule)
  */
-void cpu_idle (void)
+void cpu_idle(void)
 {
 	current_thread_info()->status |= TS_POLLING;
 	/* endless idle loop with no priority at all */
 	while (1) {
+		tick_nohz_stop_sched_tick();
 		while (!need_resched()) {
 			void (*idle)(void);
 
 			if (__get_cpu_var(cpu_idle_state))
 				__get_cpu_var(cpu_idle_state) = 0;
 
-			tick_nohz_stop_sched_tick();
-
 			rmb();
 			idle = pm_idle;
 			if (!idle)
@@ -236,6 +204,47 @@ void cpu_idle (void)
 	}
 }
 
+static void do_nothing(void *unused)
+{
+}
+
+void cpu_idle_wait(void)
+{
+	unsigned int cpu, this_cpu = get_cpu();
+	cpumask_t map, tmp = current->cpus_allowed;
+
+	set_cpus_allowed(current, cpumask_of_cpu(this_cpu));
+	put_cpu();
+
+	cpus_clear(map);
+	for_each_online_cpu(cpu) {
+		per_cpu(cpu_idle_state, cpu) = 1;
+		cpu_set(cpu, map);
+	}
+
+	__get_cpu_var(cpu_idle_state) = 0;
+
+	wmb();
+	do {
+		ssleep(1);
+		for_each_online_cpu(cpu) {
+			if (cpu_isset(cpu, map) && !per_cpu(cpu_idle_state, cpu))
+				cpu_clear(cpu, map);
+		}
+		cpus_and(map, map, cpu_online_map);
+		/*
+		 * We waited 1 sec, if a CPU still did not call idle
+		 * it may be because it is in idle and not waking up
+		 * because it has nothing to do.
+		 * Give all the remaining CPUS a kick.
+		 */
+		smp_call_function_mask(map, do_nothing, 0, 0);
+	} while (!cpus_empty(map));
+
+	set_cpus_allowed(current, tmp);
+}
+EXPORT_SYMBOL_GPL(cpu_idle_wait);
+
 /*
  * This uses new MONITOR/MWAIT instructions on P4 processors with PNI,
  * which can obviate IPI to trigger checking of need_resched.
@@ -246,13 +255,13 @@ void cpu_idle (void)
  * New with Core Duo processors, MWAIT can take some hints based on CPU
  * capability.
  */
-void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
+void mwait_idle_with_hints(unsigned long ax, unsigned long cx)
 {
 	if (!need_resched()) {
 		__monitor((void *)&current_thread_info()->flags, 0, 0);
 		smp_mb();
 		if (!need_resched())
-			__mwait(eax, ecx);
+			__mwait(ax, cx);
 	}
 }
 
@@ -271,25 +280,41 @@ static void mwait_idle(void)
 	}
 }
 
+
+static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c)
+{
+	if (force_mwait)
+		return 1;
+	/* Any C1 states supported? */
+	return c->cpuid_level >= 5 && ((cpuid_edx(5) >> 4) & 0xf) > 0;
+}
+
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 {
-	static int printed;
-	if (cpu_has(c, X86_FEATURE_MWAIT)) {
+	static int selected;
+
+	if (selected)
+		return;
+#ifdef CONFIG_X86_SMP
+	if (pm_idle == poll_idle && smp_num_siblings > 1) {
+		printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
+			" performance may degrade.\n");
+	}
+#endif
+	if (cpu_has(c, X86_FEATURE_MWAIT) && mwait_usable(c)) {
 		/*
 		 * Skip, if setup has overridden idle.
 		 * One CPU supports mwait => All CPUs supports mwait
 		 */
 		if (!pm_idle) {
-			if (!printed) {
-				printk(KERN_INFO "using mwait in idle threads.\n");
-				printed = 1;
-			}
+			printk(KERN_INFO "using mwait in idle threads.\n");
 			pm_idle = mwait_idle;
 		}
 	}
+	selected = 1;
 }
 
-static int __init idle_setup (char *str)
+static int __init idle_setup(char *str)
 {
 	if (!strcmp(str, "poll")) {
 		printk("using polling idle threads.\n");
@@ -304,13 +329,13 @@ static int __init idle_setup (char *str)
 }
 early_param("idle", idle_setup);
 
-/* Prints also some state that isn't saved in the pt_regs */ 
+/* Prints also some state that isn't saved in the pt_regs */
 void __show_regs(struct pt_regs * regs)
 {
 	unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs;
 	unsigned long d0, d1, d2, d3, d6, d7;
-	unsigned int fsindex,gsindex;
-	unsigned int ds,cs,es; 
+	unsigned int fsindex, gsindex;
+	unsigned int ds, cs, es;
 
 	printk("\n");
 	print_modules();
@@ -319,16 +344,16 @@ void __show_regs(struct pt_regs * regs)
 		init_utsname()->release,
 		(int)strcspn(init_utsname()->version, " "),
 		init_utsname()->version);
-	printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip);
-	printk_address(regs->rip); 
-	printk("RSP: %04lx:%016lx  EFLAGS: %08lx\n", regs->ss, regs->rsp,
-		regs->eflags);
+	printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip);
+	printk_address(regs->ip, 1);
+	printk("RSP: %04lx:%016lx  EFLAGS: %08lx\n", regs->ss, regs->sp,
+		regs->flags);
 	printk("RAX: %016lx RBX: %016lx RCX: %016lx\n",
-	       regs->rax, regs->rbx, regs->rcx);
+	       regs->ax, regs->bx, regs->cx);
 	printk("RDX: %016lx RSI: %016lx RDI: %016lx\n",
-	       regs->rdx, regs->rsi, regs->rdi); 
+	       regs->dx, regs->si, regs->di);
 	printk("RBP: %016lx R08: %016lx R09: %016lx\n",
-	       regs->rbp, regs->r8, regs->r9); 
+	       regs->bp, regs->r8, regs->r9);
 	printk("R10: %016lx R11: %016lx R12: %016lx\n",
 	       regs->r10, regs->r11, regs->r12); 
 	printk("R13: %016lx R14: %016lx R15: %016lx\n",
@@ -368,7 +393,7 @@ void show_regs(struct pt_regs *regs)
 {
 	printk("CPU %d:", smp_processor_id());
 	__show_regs(regs);
-	show_trace(NULL, regs, (void *)(regs + 1));
+	show_trace(NULL, regs, (void *)(regs + 1), regs->bp);
 }
 
 /*
@@ -379,7 +404,7 @@ void exit_thread(void)
 	struct task_struct *me = current;
 	struct thread_struct *t = &me->thread;
 
-	if (me->thread.io_bitmap_ptr) { 
+	if (me->thread.io_bitmap_ptr) {
 		struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
 
 		kfree(t->io_bitmap_ptr);
@@ -415,7 +440,7 @@ void flush_thread(void)
 	tsk->thread.debugreg3 = 0;
 	tsk->thread.debugreg6 = 0;
 	tsk->thread.debugreg7 = 0;
-	memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));	
+	memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
 	/*
 	 * Forget coprocessor state..
 	 */
@@ -438,26 +463,21 @@ void release_thread(struct task_struct *dead_task)
 
 static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr)
 {
-	struct user_desc ud = { 
+	struct user_desc ud = {
 		.base_addr = addr,
 		.limit = 0xfffff,
 		.seg_32bit = 1,
 		.limit_in_pages = 1,
 		.useable = 1,
 	};
-	struct n_desc_struct *desc = (void *)t->thread.tls_array;
+	struct desc_struct *desc = t->thread.tls_array;
 	desc += tls;
-	desc->a = LDT_entry_a(&ud); 
-	desc->b = LDT_entry_b(&ud); 
+	fill_ldt(desc, &ud);
 }
 
 static inline u32 read_32bit_tls(struct task_struct *t, int tls)
 {
-	struct desc_struct *desc = (void *)t->thread.tls_array;
-	desc += tls;
-	return desc->base0 | 
-		(((u32)desc->base1) << 16) | 
-		(((u32)desc->base2) << 24);
+	return get_desc_base(&t->thread.tls_array[tls]);
 }
 
 /*
@@ -469,7 +489,7 @@ void prepare_to_copy(struct task_struct *tsk)
 	unlazy_fpu(tsk);
 }
 
-int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp, 
+int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 		unsigned long unused,
 	struct task_struct * p, struct pt_regs * regs)
 {
@@ -481,14 +501,14 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp,
 			(THREAD_SIZE + task_stack_page(p))) - 1;
 	*childregs = *regs;
 
-	childregs->rax = 0;
-	childregs->rsp = rsp;
-	if (rsp == ~0UL)
-		childregs->rsp = (unsigned long)childregs;
+	childregs->ax = 0;
+	childregs->sp = sp;
+	if (sp == ~0UL)
+		childregs->sp = (unsigned long)childregs;
 
-	p->thread.rsp = (unsigned long) childregs;
-	p->thread.rsp0 = (unsigned long) (childregs+1);
-	p->thread.userrsp = me->thread.userrsp; 
+	p->thread.sp = (unsigned long) childregs;
+	p->thread.sp0 = (unsigned long) (childregs+1);
+	p->thread.usersp = me->thread.usersp;
 
 	set_tsk_thread_flag(p, TIF_FORK);
 
@@ -509,7 +529,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp,
 		memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr,
 				IO_BITMAP_BYTES);
 		set_tsk_thread_flag(p, TIF_IO_BITMAP);
-	} 
+	}
 
 	/*
 	 * Set a new TLS for the child thread?
@@ -517,7 +537,8 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp,
 	if (clone_flags & CLONE_SETTLS) {
 #ifdef CONFIG_IA32_EMULATION
 		if (test_thread_flag(TIF_IA32))
-			err = ia32_child_tls(p, childregs); 
+			err = do_set_thread_area(p, -1,
+				(struct user_desc __user *)childregs->si, 0);
 		else 			
 #endif	 
 			err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8); 
@@ -536,17 +557,30 @@ out:
 /*
  * This special macro can be used to load a debugging register
  */
-#define loaddebug(thread,r) set_debugreg(thread->debugreg ## r, r)
+#define loaddebug(thread, r) set_debugreg(thread->debugreg ## r, r)
 
 static inline void __switch_to_xtra(struct task_struct *prev_p,
-			     	    struct task_struct *next_p,
-			     	    struct tss_struct *tss)
+				    struct task_struct *next_p,
+				    struct tss_struct *tss)
 {
 	struct thread_struct *prev, *next;
+	unsigned long debugctl;
 
 	prev = &prev_p->thread,
 	next = &next_p->thread;
 
+	debugctl = prev->debugctlmsr;
+	if (next->ds_area_msr != prev->ds_area_msr) {
+		/* we clear debugctl to make sure DS
+		 * is not in use when we change it */
+		debugctl = 0;
+		wrmsrl(MSR_IA32_DEBUGCTLMSR, 0);
+		wrmsrl(MSR_IA32_DS_AREA, next->ds_area_msr);
+	}
+
+	if (next->debugctlmsr != debugctl)
+		wrmsrl(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr);
+
 	if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
 		loaddebug(next, 0);
 		loaddebug(next, 1);
@@ -570,12 +604,18 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
 		 */
 		memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
 	}
+
+	if (test_tsk_thread_flag(prev_p, TIF_BTS_TRACE_TS))
+		ptrace_bts_take_timestamp(prev_p, BTS_TASK_DEPARTS);
+
+	if (test_tsk_thread_flag(next_p, TIF_BTS_TRACE_TS))
+		ptrace_bts_take_timestamp(next_p, BTS_TASK_ARRIVES);
 }
 
 /*
  *	switch_to(x,y) should switch tasks from x to y.
  *
- * This could still be optimized: 
+ * This could still be optimized:
  * - fold all the options into a flag word and test it with a single test.
  * - could test fs/gs bitsliced
  *
@@ -586,7 +626,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 {
 	struct thread_struct *prev = &prev_p->thread,
 				 *next = &next_p->thread;
-	int cpu = smp_processor_id();  
+	int cpu = smp_processor_id();
 	struct tss_struct *tss = &per_cpu(init_tss, cpu);
 
 	/* we're going to use this soon, after a few expensive things */
@@ -596,7 +636,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	/*
 	 * Reload esp0, LDT and the page table pointer:
 	 */
-	tss->rsp0 = next->rsp0;
+	load_sp0(tss, next);
 
 	/* 
 	 * Switch DS and ES.
@@ -655,8 +695,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	/* 
 	 * Switch the PDA and FPU contexts.
 	 */
-	prev->userrsp = read_pda(oldrsp); 
-	write_pda(oldrsp, next->userrsp); 
+	prev->usersp = read_pda(oldrsp);
+	write_pda(oldrsp, next->usersp);
 	write_pda(pcurrent, next_p); 
 
 	write_pda(kernelstack,
@@ -673,8 +713,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	/*
 	 * Now maybe reload the debug registers and handle I/O bitmaps
 	 */
-	if (unlikely((task_thread_info(next_p)->flags & _TIF_WORK_CTXSW))
-	    || test_tsk_thread_flag(prev_p, TIF_IO_BITMAP))
+	if (unlikely(task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT ||
+		     task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV))
 		__switch_to_xtra(prev_p, next_p, tss);
 
 	/* If the task has used fpu the last 5 timeslices, just do a full
@@ -689,7 +729,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 /*
  * sys_execve() executes a new program.
  */
-asmlinkage 
+asmlinkage
 long sys_execve(char __user *name, char __user * __user *argv,
 		char __user * __user *envp, struct pt_regs regs)
 {
@@ -701,11 +741,6 @@ long sys_execve(char __user *name, char __user * __user *argv,
 	if (IS_ERR(filename)) 
 		return error;
 	error = do_execve(filename, argv, envp, &regs); 
-	if (error == 0) {
-		task_lock(current);
-		current->ptrace &= ~PT_DTRACE;
-		task_unlock(current);
-	}
 	putname(filename);
 	return error;
 }
@@ -715,18 +750,18 @@ void set_personality_64bit(void)
 	/* inherit personality from parent */
 
 	/* Make sure to be in 64bit mode */
-	clear_thread_flag(TIF_IA32); 
+	clear_thread_flag(TIF_IA32);
 
 	/* TBD: overwrites user setup. Should have two bits.
 	   But 64bit processes have always behaved this way,
 	   so it's not too bad. The main problem is just that
-   	   32bit childs are affected again. */
+	   32bit childs are affected again. */
 	current->personality &= ~READ_IMPLIES_EXEC;
 }
 
 asmlinkage long sys_fork(struct pt_regs *regs)
 {
-	return do_fork(SIGCHLD, regs->rsp, regs, 0, NULL, NULL);
+	return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
 }
 
 asmlinkage long
@@ -734,7 +769,7 @@ sys_clone(unsigned long clone_flags, unsigned long newsp,
 	  void __user *parent_tid, void __user *child_tid, struct pt_regs *regs)
 {
 	if (!newsp)
-		newsp = regs->rsp;
+		newsp = regs->sp;
 	return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
 }
 
@@ -750,29 +785,29 @@ sys_clone(unsigned long clone_flags, unsigned long newsp,
  */
 asmlinkage long sys_vfork(struct pt_regs *regs)
 {
-	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->rsp, regs, 0,
+	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0,
 		    NULL, NULL);
 }
 
 unsigned long get_wchan(struct task_struct *p)
 {
 	unsigned long stack;
-	u64 fp,rip;
+	u64 fp,ip;
 	int count = 0;
 
 	if (!p || p == current || p->state==TASK_RUNNING)
 		return 0; 
 	stack = (unsigned long)task_stack_page(p);
-	if (p->thread.rsp < stack || p->thread.rsp > stack+THREAD_SIZE)
+	if (p->thread.sp < stack || p->thread.sp > stack+THREAD_SIZE)
 		return 0;
-	fp = *(u64 *)(p->thread.rsp);
+	fp = *(u64 *)(p->thread.sp);
 	do { 
 		if (fp < (unsigned long)stack ||
 		    fp > (unsigned long)stack+THREAD_SIZE)
 			return 0; 
-		rip = *(u64 *)(fp+8); 
-		if (!in_sched_functions(rip))
-			return rip; 
+		ip = *(u64 *)(fp+8);
+		if (!in_sched_functions(ip))
+			return ip;
 		fp = *(u64 *)fp; 
 	} while (count++ < 16); 
 	return 0;
@@ -813,19 +848,19 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 		/* Not strictly needed for fs, but do it for symmetry
 		   with gs */
 		if (addr >= TASK_SIZE_OF(task))
-			return -EPERM; 
+			return -EPERM;
 		cpu = get_cpu();
-		/* handle small bases via the GDT because that's faster to 
+		/* handle small bases via the GDT because that's faster to
 		   switch. */
-		if (addr <= 0xffffffff) { 
+		if (addr <= 0xffffffff) {
 			set_32bit_tls(task, FS_TLS, addr);
-			if (doit) { 
-				load_TLS(&task->thread, cpu); 
+			if (doit) {
+				load_TLS(&task->thread, cpu);
 				asm volatile("movl %0,%%fs" :: "r"(FS_TLS_SEL));
 			}
 			task->thread.fsindex = FS_TLS_SEL;
 			task->thread.fs = 0;
-		} else { 
+		} else {
 			task->thread.fsindex = 0;
 			task->thread.fs = addr;
 			if (doit) {
@@ -837,24 +872,24 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 		}
 		put_cpu();
 		break;
-	case ARCH_GET_FS: { 
-		unsigned long base; 
+	case ARCH_GET_FS: {
+		unsigned long base;
 		if (task->thread.fsindex == FS_TLS_SEL)
 			base = read_32bit_tls(task, FS_TLS);
 		else if (doit)
 			rdmsrl(MSR_FS_BASE, base);
 		else
 			base = task->thread.fs;
-		ret = put_user(base, (unsigned long __user *)addr); 
-		break; 
+		ret = put_user(base, (unsigned long __user *)addr);
+		break;
 	}
-	case ARCH_GET_GS: { 
+	case ARCH_GET_GS: {
 		unsigned long base;
 		unsigned gsindex;
 		if (task->thread.gsindex == GS_TLS_SEL)
 			base = read_32bit_tls(task, GS_TLS);
 		else if (doit) {
- 			asm("movl %%gs,%0" : "=r" (gsindex));
+			asm("movl %%gs,%0" : "=r" (gsindex));
 			if (gsindex)
 				rdmsrl(MSR_KERNEL_GS_BASE, base);
 			else
@@ -862,39 +897,21 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 		}
 		else
 			base = task->thread.gs;
-		ret = put_user(base, (unsigned long __user *)addr); 
+		ret = put_user(base, (unsigned long __user *)addr);
 		break;
 	}
 
 	default:
 		ret = -EINVAL;
 		break;
-	} 
+	}
 
-	return ret;	
-} 
+	return ret;
+}
 
 long sys_arch_prctl(int code, unsigned long addr)
 {
 	return do_arch_prctl(current, code, addr);
-} 
-
-/* 
- * Capture the user space registers if the task is not running (in user space)
- */
-int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
-{
-	struct pt_regs *pp, ptregs;
-
-	pp = task_pt_regs(tsk);
-
-	ptregs = *pp; 
-	ptregs.cs &= 0xffff;
-	ptregs.ss &= 0xffff;
-
-	elf_core_copy_regs(regs, &ptregs);
- 
-	return 1;
 }
 
 unsigned long arch_align_stack(unsigned long sp)
@@ -903,3 +920,9 @@ unsigned long arch_align_stack(unsigned long sp)
 		sp -= get_random_int() % 8192;
 	return sp & ~0xf;
 }
+
+unsigned long arch_randomize_brk(struct mm_struct *mm)
+{
+	unsigned long range_end = mm->brk + 0x02000000;
+	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
+}