1 files changed, 187 insertions, 481 deletions

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index e12e0e4dd25..ca5b02d405c 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -14,8 +14,6 @@
  * This file handles the architecture-dependent parts of process handling..
  */
 
-#include <stdarg.h>
-
 #include <linux/cpu.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
@@ -27,259 +25,108 @@
 #include <linux/slab.h>
 #include <linux/user.h>
 #include <linux/interrupt.h>
-#include <linux/utsname.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/ptrace.h>
-#include <linux/random.h>
 #include <linux/notifier.h>
 #include <linux/kprobes.h>
 #include <linux/kdebug.h>
-#include <linux/tick.h>
 #include <linux/prctl.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/ftrace.h>
 
-#include <asm/uaccess.h>
 #include <asm/pgtable.h>
-#include <asm/system.h>
-#include <asm/io.h>
 #include <asm/processor.h>
 #include <asm/i387.h>
+#include <asm/fpu-internal.h>
 #include <asm/mmu_context.h>
-#include <asm/pda.h>
 #include <asm/prctl.h>
 #include <asm/desc.h>
 #include <asm/proto.h>
 #include <asm/ia32.h>
 #include <asm/idle.h>
+#include <asm/syscalls.h>
+#include <asm/debugreg.h>
+#include <asm/switch_to.h>
 
 asmlinkage extern void ret_from_fork(void);
 
-unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED;
-
-static ATOMIC_NOTIFIER_HEAD(idle_notifier);
-
-void idle_notifier_register(struct notifier_block *n)
-{
-	atomic_notifier_chain_register(&idle_notifier, n);
-}
-
-void enter_idle(void)
-{
-	write_pda(isidle, 1);
-	atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
-}
-
-static void __exit_idle(void)
-{
-	if (test_and_clear_bit_pda(0, isidle) == 0)
-		return;
-	atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
-}
-
-/* Called from interrupts to signify idle end */
-void exit_idle(void)
-{
-	/* idle loop has pid 0 */
-	if (current->pid)
-		return;
-	__exit_idle();
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-DECLARE_PER_CPU(int, cpu_state);
-
-#include <asm/nmi.h>
-/* We halt the CPU with physical CPU hotplug */
-static inline void play_dead(void)
-{
-	idle_task_exit();
-	c1e_remove_cpu(raw_smp_processor_id());
-
-	mb();
-	/* Ack it */
-	__get_cpu_var(cpu_state) = CPU_DEAD;
-
-	local_irq_disable();
-	/* mask all interrupts, flush any and all caches, and halt */
-	wbinvd_halt();
-}
-#else
-static inline void play_dead(void)
-{
-	BUG();
-}
-#endif /* CONFIG_HOTPLUG_CPU */
-
-/*
- * The idle thread. There's no useful work to be
- * done, so just try to conserve power and have a
- * low exit latency (ie sit in a loop waiting for
- * somebody to say that they'd like to reschedule)
- */
-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(1);
-		while (!need_resched()) {
-
-			rmb();
-
-			if (cpu_is_offline(smp_processor_id()))
-				play_dead();
-			/*
-			 * Idle routines should keep interrupts disabled
-			 * from here on, until they go to idle.
-			 * Otherwise, idle callbacks can misfire.
-			 */
-			local_irq_disable();
-			enter_idle();
-			/* Don't trace irqs off for idle */
-			stop_critical_timings();
-			pm_idle();
-			start_critical_timings();
-			/* In many cases the interrupt that ended idle
-			   has already called exit_idle. But some idle
-			   loops can be woken up without interrupt. */
-			__exit_idle();
-		}
-
-		tick_nohz_restart_sched_tick();
-		preempt_enable_no_resched();
-		schedule();
-		preempt_disable();
-	}
-}
+__visible DEFINE_PER_CPU(unsigned long, old_rsp);
 
 /* Prints also some state that isn't saved in the pt_regs */
-void __show_regs(struct pt_regs * regs)
+void __show_regs(struct pt_regs *regs, int all)
 {
 	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;
 
-	printk("\n");
-	print_modules();
-	printk("Pid: %d, comm: %.20s %s %s %.*s\n",
-		current->pid, current->comm, print_tainted(),
-		init_utsname()->release,
-		(int)strcspn(init_utsname()->version, " "),
-		init_utsname()->version);
-	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",
+	printk(KERN_DEFAULT "RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip);
+	printk_address(regs->ip);
+	printk(KERN_DEFAULT "RSP: %04lx:%016lx  EFLAGS: %08lx\n", regs->ss,
+			regs->sp, regs->flags);
+	printk(KERN_DEFAULT "RAX: %016lx RBX: %016lx RCX: %016lx\n",
 	       regs->ax, regs->bx, regs->cx);
-	printk("RDX: %016lx RSI: %016lx RDI: %016lx\n",
+	printk(KERN_DEFAULT "RDX: %016lx RSI: %016lx RDI: %016lx\n",
 	       regs->dx, regs->si, regs->di);
-	printk("RBP: %016lx R08: %016lx R09: %016lx\n",
+	printk(KERN_DEFAULT "RBP: %016lx R08: %016lx R09: %016lx\n",
 	       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",
-	       regs->r13, regs->r14, regs->r15); 
-
-	asm("movl %%ds,%0" : "=r" (ds)); 
-	asm("movl %%cs,%0" : "=r" (cs)); 
-	asm("movl %%es,%0" : "=r" (es)); 
+	printk(KERN_DEFAULT "R10: %016lx R11: %016lx R12: %016lx\n",
+	       regs->r10, regs->r11, regs->r12);
+	printk(KERN_DEFAULT "R13: %016lx R14: %016lx R15: %016lx\n",
+	       regs->r13, regs->r14, regs->r15);
+
+	asm("movl %%ds,%0" : "=r" (ds));
+	asm("movl %%cs,%0" : "=r" (cs));
+	asm("movl %%es,%0" : "=r" (es));
 	asm("movl %%fs,%0" : "=r" (fsindex));
 	asm("movl %%gs,%0" : "=r" (gsindex));
 
 	rdmsrl(MSR_FS_BASE, fs);
-	rdmsrl(MSR_GS_BASE, gs); 
-	rdmsrl(MSR_KERNEL_GS_BASE, shadowgs); 
+	rdmsrl(MSR_GS_BASE, gs);
+	rdmsrl(MSR_KERNEL_GS_BASE, shadowgs);
+
+	if (!all)
+		return;
 
 	cr0 = read_cr0();
 	cr2 = read_cr2();
 	cr3 = read_cr3();
 	cr4 = read_cr4();
 
-	printk("FS:  %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", 
-	       fs,fsindex,gs,gsindex,shadowgs); 
-	printk("CS:  %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds, es, cr0); 
-	printk("CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3, cr4);
+	printk(KERN_DEFAULT "FS:  %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
+	       fs, fsindex, gs, gsindex, shadowgs);
+	printk(KERN_DEFAULT "CS:  %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds,
+			es, cr0);
+	printk(KERN_DEFAULT "CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3,
+			cr4);
 
 	get_debugreg(d0, 0);
 	get_debugreg(d1, 1);
 	get_debugreg(d2, 2);
-	printk("DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2);
 	get_debugreg(d3, 3);
 	get_debugreg(d6, 6);
 	get_debugreg(d7, 7);
-	printk("DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7);
-}
-
-void show_regs(struct pt_regs *regs)
-{
-	printk("CPU %d:", smp_processor_id());
-	__show_regs(regs);
-	show_trace(NULL, regs, (void *)(regs + 1), regs->bp);
-}
-
-/*
- * Free current thread data structures etc..
- */
-void exit_thread(void)
-{
-	struct task_struct *me = current;
-	struct thread_struct *t = &me->thread;
-
-	if (me->thread.io_bitmap_ptr) {
-		struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
 
-		kfree(t->io_bitmap_ptr);
-		t->io_bitmap_ptr = NULL;
-		clear_thread_flag(TIF_IO_BITMAP);
-		/*
-		 * Careful, clear this in the TSS too:
-		 */
-		memset(tss->io_bitmap, 0xff, t->io_bitmap_max);
-		t->io_bitmap_max = 0;
-		put_cpu();
-	}
-}
+	/* Only print out debug registers if they are in their non-default state. */
+	if ((d0 == 0) && (d1 == 0) && (d2 == 0) && (d3 == 0) &&
+	    (d6 == DR6_RESERVED) && (d7 == 0x400))
+		return;
 
-void flush_thread(void)
-{
-	struct task_struct *tsk = current;
+	printk(KERN_DEFAULT "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2);
+	printk(KERN_DEFAULT "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7);
 
-	if (test_tsk_thread_flag(tsk, TIF_ABI_PENDING)) {
-		clear_tsk_thread_flag(tsk, TIF_ABI_PENDING);
-		if (test_tsk_thread_flag(tsk, TIF_IA32)) {
-			clear_tsk_thread_flag(tsk, TIF_IA32);
-		} else {
-			set_tsk_thread_flag(tsk, TIF_IA32);
-			current_thread_info()->status |= TS_COMPAT;
-		}
-	}
-	clear_tsk_thread_flag(tsk, TIF_DEBUG);
-
-	tsk->thread.debugreg0 = 0;
-	tsk->thread.debugreg1 = 0;
-	tsk->thread.debugreg2 = 0;
-	tsk->thread.debugreg3 = 0;
-	tsk->thread.debugreg6 = 0;
-	tsk->thread.debugreg7 = 0;
-	memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
-	/*
-	 * Forget coprocessor state..
-	 */
-	tsk->fpu_counter = 0;
-	clear_fpu(tsk);
-	clear_used_math();
 }
 
 void release_thread(struct task_struct *dead_task)
 {
 	if (dead_task->mm) {
 		if (dead_task->mm->context.size) {
-			printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
-					dead_task->comm,
-					dead_task->mm->context.ldt,
-					dead_task->mm->context.size);
+			pr_warn("WARNING: dead process %s still has LDT? <%p/%d>\n",
+				dead_task->comm,
+				dead_task->mm->context.ldt,
+				dead_task->mm->context.size);
 			BUG();
 		}
 	}
@@ -304,54 +151,57 @@ static inline u32 read_32bit_tls(struct task_struct *t, int tls)
 	return get_desc_base(&t->thread.tls_array[tls]);
 }
 
-/*
- * This gets called before we allocate a new thread and copy
- * the current task into it.
- */
-void prepare_to_copy(struct task_struct *tsk)
-{
-	unlazy_fpu(tsk);
-}
-
-int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
-		unsigned long unused,
-	struct task_struct * p, struct pt_regs * regs)
+int copy_thread(unsigned long clone_flags, unsigned long sp,
+		unsigned long arg, struct task_struct *p)
 {
 	int err;
-	struct pt_regs * childregs;
+	struct pt_regs *childregs;
 	struct task_struct *me = current;
 
-	childregs = ((struct pt_regs *)
-			(THREAD_SIZE + task_stack_page(p))) - 1;
-	*childregs = *regs;
-
-	childregs->ax = 0;
-	childregs->sp = sp;
-	if (sp == ~0UL)
-		childregs->sp = (unsigned long)childregs;
-
+	p->thread.sp0 = (unsigned long)task_stack_page(p) + THREAD_SIZE;
+	childregs = task_pt_regs(p);
 	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);
-
-	p->thread.fs = me->thread.fs;
-	p->thread.gs = me->thread.gs;
+	p->thread.fpu_counter = 0;
+	p->thread.io_bitmap_ptr = NULL;
 
 	savesegment(gs, p->thread.gsindex);
+	p->thread.gs = p->thread.gsindex ? 0 : me->thread.gs;
 	savesegment(fs, p->thread.fsindex);
+	p->thread.fs = p->thread.fsindex ? 0 : me->thread.fs;
 	savesegment(es, p->thread.es);
 	savesegment(ds, p->thread.ds);
+	memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
+
+	if (unlikely(p->flags & PF_KTHREAD)) {
+		/* kernel thread */
+		memset(childregs, 0, sizeof(struct pt_regs));
+		childregs->sp = (unsigned long)childregs;
+		childregs->ss = __KERNEL_DS;
+		childregs->bx = sp; /* function */
+		childregs->bp = arg;
+		childregs->orig_ax = -1;
+		childregs->cs = __KERNEL_CS | get_kernel_rpl();
+		childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_FIXED;
+		return 0;
+	}
+	*childregs = *current_pt_regs();
+
+	childregs->ax = 0;
+	if (sp)
+		childregs->sp = sp;
+
+	err = -ENOMEM;
+	memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
 
 	if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
-		p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
+		p->thread.io_bitmap_ptr = kmemdup(me->thread.io_bitmap_ptr,
+						  IO_BITMAP_BYTES, GFP_KERNEL);
 		if (!p->thread.io_bitmap_ptr) {
 			p->thread.io_bitmap_max = 0;
 			return -ENOMEM;
 		}
-		memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr,
-				IO_BITMAP_BYTES);
 		set_tsk_thread_flag(p, TIF_IO_BITMAP);
 	}
 
@@ -363,10 +213,10 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 		if (test_thread_flag(TIF_IA32))
 			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); 
-		if (err) 
+		else
+#endif
+			err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8);
+		if (err)
 			goto out;
 	}
 	err = 0;
@@ -375,156 +225,44 @@ out:
 		kfree(p->thread.io_bitmap_ptr);
 		p->thread.io_bitmap_max = 0;
 	}
+
 	return err;
 }
 
-void
-start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
+static void
+start_thread_common(struct pt_regs *regs, unsigned long new_ip,
+		    unsigned long new_sp,
+		    unsigned int _cs, unsigned int _ss, unsigned int _ds)
 {
 	loadsegment(fs, 0);
-	loadsegment(es, 0);
-	loadsegment(ds, 0);
+	loadsegment(es, _ds);
+	loadsegment(ds, _ds);
 	load_gs_index(0);
+	current->thread.usersp	= new_sp;
 	regs->ip		= new_ip;
 	regs->sp		= new_sp;
-	write_pda(oldrsp, new_sp);
-	regs->cs		= __USER_CS;
-	regs->ss		= __USER_DS;
-	regs->flags		= 0x200;
-	set_fs(USER_DS);
-	/*
-	 * Free the old FP and other extended state
-	 */
-	free_thread_xstate(current);
+	this_cpu_write(old_rsp, new_sp);
+	regs->cs		= _cs;
+	regs->ss		= _ss;
+	regs->flags		= X86_EFLAGS_IF;
 }
-EXPORT_SYMBOL_GPL(start_thread);
 
-static void hard_disable_TSC(void)
-{
-	write_cr4(read_cr4() | X86_CR4_TSD);
-}
-
-void disable_TSC(void)
-{
-	preempt_disable();
-	if (!test_and_set_thread_flag(TIF_NOTSC))
-		/*
-		 * Must flip the CPU state synchronously with
-		 * TIF_NOTSC in the current running context.
-		 */
-		hard_disable_TSC();
-	preempt_enable();
-}
-
-static void hard_enable_TSC(void)
-{
-	write_cr4(read_cr4() & ~X86_CR4_TSD);
-}
-
-static void enable_TSC(void)
+void
+start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
 {
-	preempt_disable();
-	if (test_and_clear_thread_flag(TIF_NOTSC))
-		/*
-		 * Must flip the CPU state synchronously with
-		 * TIF_NOTSC in the current running context.
-		 */
-		hard_enable_TSC();
-	preempt_enable();
+	start_thread_common(regs, new_ip, new_sp,
+			    __USER_CS, __USER_DS, 0);
 }
 
-int get_tsc_mode(unsigned long adr)
+#ifdef CONFIG_IA32_EMULATION
+void start_thread_ia32(struct pt_regs *regs, u32 new_ip, u32 new_sp)
 {
-	unsigned int val;
-
-	if (test_thread_flag(TIF_NOTSC))
-		val = PR_TSC_SIGSEGV;
-	else
-		val = PR_TSC_ENABLE;
-
-	return put_user(val, (unsigned int __user *)adr);
+	start_thread_common(regs, new_ip, new_sp,
+			    test_thread_flag(TIF_X32)
+			    ? __USER_CS : __USER32_CS,
+			    __USER_DS, __USER_DS);
 }
-
-int set_tsc_mode(unsigned int val)
-{
-	if (val == PR_TSC_SIGSEGV)
-		disable_TSC();
-	else if (val == PR_TSC_ENABLE)
-		enable_TSC();
-	else
-		return -EINVAL;
-
-	return 0;
-}
-
-/*
- * This special macro can be used to load a debugging register
- */
-#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 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;
-		update_debugctlmsr(0);
-		wrmsrl(MSR_IA32_DS_AREA, next->ds_area_msr);
-	}
-
-	if (next->debugctlmsr != debugctl)
-		update_debugctlmsr(next->debugctlmsr);
-
-	if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
-		loaddebug(next, 0);
-		loaddebug(next, 1);
-		loaddebug(next, 2);
-		loaddebug(next, 3);
-		/* no 4 and 5 */
-		loaddebug(next, 6);
-		loaddebug(next, 7);
-	}
-
-	if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^
-	    test_tsk_thread_flag(next_p, TIF_NOTSC)) {
-		/* prev and next are different */
-		if (test_tsk_thread_flag(next_p, TIF_NOTSC))
-			hard_disable_TSC();
-		else
-			hard_enable_TSC();
-	}
-
-	if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
-		/*
-		 * Copy the relevant range of the IO bitmap.
-		 * Normally this is 128 bytes or less:
-		 */
-		memcpy(tss->io_bitmap, next->io_bitmap_ptr,
-		       max(prev->io_bitmap_max, next->io_bitmap_max));
-	} else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) {
-		/*
-		 * Clear any possible leftover bits:
-		 */
-		memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
-	}
-
-#ifdef X86_BTS
-	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);
 #endif
-}
 
 /*
  *	switch_to(x,y) should switch tasks from x to y.
@@ -534,8 +272,9 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
  * - could test fs/gs bitsliced
  *
  * Kprobes not supported here. Set the probe on schedule instead.
+ * Function graph tracer not supported too.
  */
-struct task_struct *
+__visible __notrace_funcgraph struct task_struct *
 __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 {
 	struct thread_struct *prev = &prev_p->thread;
@@ -543,23 +282,22 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	int cpu = smp_processor_id();
 	struct tss_struct *tss = &per_cpu(init_tss, cpu);
 	unsigned fsindex, gsindex;
+	fpu_switch_t fpu;
 
-	/* we're going to use this soon, after a few expensive things */
-	if (next_p->fpu_counter>5)
-		prefetch(next->xstate);
+	fpu = switch_fpu_prepare(prev_p, next_p, cpu);
 
 	/*
 	 * Reload esp0, LDT and the page table pointer:
 	 */
 	load_sp0(tss, next);
 
-	/* 
+	/*
 	 * Switch DS and ES.
 	 * This won't pick up thread selector changes, but I guess that is ok.
 	 */
 	savesegment(es, prev->es);
 	if (unlikely(next->es | prev->es))
-		loadsegment(es, next->es); 
+		loadsegment(es, next->es);
 
 	savesegment(ds, prev->ds);
 	if (unlikely(next->ds | prev->ds))
@@ -583,9 +321,9 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	 * done before math_state_restore, so the TS bit is up
 	 * to date.
 	 */
-	arch_leave_lazy_cpu_mode();
+	arch_end_context_switch(next_p);
 
-	/* 
+	/*
 	 * Switch FS and GS.
 	 *
 	 * Segment register != 0 always requires a reload.  Also
@@ -594,13 +332,13 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	 */
 	if (unlikely(fsindex | next->fsindex | prev->fs)) {
 		loadsegment(fs, next->fsindex);
-		/* 
+		/*
 		 * Check if the user used a selector != 0; if yes
 		 *  clear 64bit base, since overloaded base is always
 		 *  mapped to the Null selector
 		 */
 		if (fsindex)
-			prev->fs = 0;				
+			prev->fs = 0;
 	}
 	/* when next process has a 64bit base use it */
 	if (next->fs)
@@ -610,33 +348,32 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	if (unlikely(gsindex | next->gsindex | prev->gs)) {
 		load_gs_index(next->gsindex);
 		if (gsindex)
-			prev->gs = 0;				
+			prev->gs = 0;
 	}
 	if (next->gs)
 		wrmsrl(MSR_KERNEL_GS_BASE, next->gs);
 	prev->gsindex = gsindex;
 
-	/* Must be after DS reload */
-	unlazy_fpu(prev_p);
+	switch_fpu_finish(next_p, fpu);
 
-	/* 
+	/*
 	 * Switch the PDA and FPU contexts.
 	 */
-	prev->usersp = read_pda(oldrsp);
-	write_pda(oldrsp, next->usersp);
-	write_pda(pcurrent, next_p); 
+	prev->usersp = this_cpu_read(old_rsp);
+	this_cpu_write(old_rsp, next->usersp);
+	this_cpu_write(current_task, next_p);
 
-	write_pda(kernelstack,
-		  (unsigned long)task_stack_page(next_p) +
-		  THREAD_SIZE - PDA_STACKOFFSET);
-#ifdef CONFIG_CC_STACKPROTECTOR
-	write_pda(stack_canary, next_p->stack_canary);
 	/*
-	 * Build time only check to make sure the stack_canary is at
-	 * offset 40 in the pda; this is a gcc ABI requirement
+	 * If it were not for PREEMPT_ACTIVE we could guarantee that the
+	 * preempt_count of all tasks was equal here and this would not be
+	 * needed.
 	 */
-	BUILD_BUG_ON(offsetof(struct x8664_pda, stack_canary) != 40);
-#endif
+	task_thread_info(prev_p)->saved_preempt_count = this_cpu_read(__preempt_count);
+	this_cpu_write(__preempt_count, task_thread_info(next_p)->saved_preempt_count);
+
+	this_cpu_write(kernel_stack,
+		  (unsigned long)task_stack_page(next_p) +
+		  THREAD_SIZE - KERNEL_STACK_OFFSET);
 
 	/*
 	 * Now maybe reload the debug registers and handle I/O bitmaps
@@ -645,43 +382,21 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 		     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
-	 * restore of the math state immediately to avoid the trap; the
-	 * chances of needing FPU soon are obviously high now
-	 *
-	 * tsk_used_math() checks prevent calling math_state_restore(),
-	 * which can sleep in the case of !tsk_used_math()
-	 */
-	if (tsk_used_math(next_p) && next_p->fpu_counter > 5)
-		math_state_restore();
 	return prev_p;
 }
 
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage
-long sys_execve(char __user *name, char __user * __user *argv,
-		char __user * __user *envp, struct pt_regs *regs)
-{
-	long error;
-	char * filename;
-
-	filename = getname(name);
-	error = PTR_ERR(filename);
-	if (IS_ERR(filename))
-		return error;
-	error = do_execve(filename, argv, envp, regs);
-	putname(filename);
-	return error;
-}
-
 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_ADDR32);
+	clear_thread_flag(TIF_X32);
+
+	/* Ensure the corresponding mm is not marked. */
+	if (current->mm)
+		current->mm->context.ia32_compat = 0;
 
 	/* TBD: overwrites user setup. Should have two bits.
 	   But 64bit processes have always behaved this way,
@@ -690,88 +405,87 @@ void set_personality_64bit(void)
 	current->personality &= ~READ_IMPLIES_EXEC;
 }
 
-asmlinkage long sys_fork(struct pt_regs *regs)
-{
-	return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
-}
-
-asmlinkage long
-sys_clone(unsigned long clone_flags, unsigned long newsp,
-	  void __user *parent_tid, void __user *child_tid, struct pt_regs *regs)
+void set_personality_ia32(bool x32)
 {
-	if (!newsp)
-		newsp = regs->sp;
-	return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
-}
+	/* inherit personality from parent */
 
-/*
- * This is trivial, and on the face of it looks like it
- * could equally well be done in user mode.
- *
- * Not so, for quite unobvious reasons - register pressure.
- * In user mode vfork() cannot have a stack frame, and if
- * done by calling the "clone()" system call directly, you
- * do not have enough call-clobbered registers to hold all
- * the information you need.
- */
-asmlinkage long sys_vfork(struct pt_regs *regs)
-{
-	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0,
-		    NULL, NULL);
+	/* Make sure to be in 32bit mode */
+	set_thread_flag(TIF_ADDR32);
+
+	/* Mark the associated mm as containing 32-bit tasks. */
+	if (x32) {
+		clear_thread_flag(TIF_IA32);
+		set_thread_flag(TIF_X32);
+		if (current->mm)
+			current->mm->context.ia32_compat = TIF_X32;
+		current->personality &= ~READ_IMPLIES_EXEC;
+		/* is_compat_task() uses the presence of the x32
+		   syscall bit flag to determine compat status */
+		current_thread_info()->status &= ~TS_COMPAT;
+	} else {
+		set_thread_flag(TIF_IA32);
+		clear_thread_flag(TIF_X32);
+		if (current->mm)
+			current->mm->context.ia32_compat = TIF_IA32;
+		current->personality |= force_personality32;
+		/* Prepare the first "return" to user space */
+		current_thread_info()->status |= TS_COMPAT;
+	}
 }
+EXPORT_SYMBOL_GPL(set_personality_ia32);
 
 unsigned long get_wchan(struct task_struct *p)
 {
 	unsigned long stack;
-	u64 fp,ip;
+	u64 fp, ip;
 	int count = 0;
 
-	if (!p || p == current || p->state==TASK_RUNNING)
-		return 0; 
+	if (!p || p == current || p->state == TASK_RUNNING)
+		return 0;
 	stack = (unsigned long)task_stack_page(p);
-	if (p->thread.sp < stack || p->thread.sp > stack+THREAD_SIZE)
+	if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE)
 		return 0;
 	fp = *(u64 *)(p->thread.sp);
-	do { 
+	do {
 		if (fp < (unsigned long)stack ||
-		    fp > (unsigned long)stack+THREAD_SIZE)
-			return 0; 
+		    fp >= (unsigned long)stack+THREAD_SIZE)
+			return 0;
 		ip = *(u64 *)(fp+8);
 		if (!in_sched_functions(ip))
 			return ip;
-		fp = *(u64 *)fp; 
-	} while (count++ < 16); 
+		fp = *(u64 *)fp;
+	} while (count++ < 16);
 	return 0;
 }
 
 long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
-{ 
-	int ret = 0; 
+{
+	int ret = 0;
 	int doit = task == current;
 	int cpu;
 
-	switch (code) { 
+	switch (code) {
 	case ARCH_SET_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) {  
-			set_32bit_tls(task, GS_TLS, addr); 
-			if (doit) { 
+		if (addr <= 0xffffffff) {
+			set_32bit_tls(task, GS_TLS, addr);
+			if (doit) {
 				load_TLS(&task->thread, cpu);
-				load_gs_index(GS_TLS_SEL); 
+				load_gs_index(GS_TLS_SEL);
 			}
-			task->thread.gsindex = GS_TLS_SEL; 
+			task->thread.gsindex = GS_TLS_SEL;
 			task->thread.gs = 0;
-		} else { 
+		} else {
 			task->thread.gsindex = 0;
 			task->thread.gs = addr;
 			if (doit) {
 				load_gs_index(0);
-				ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr);
-			} 
+				ret = wrmsrl_safe(MSR_KERNEL_GS_BASE, addr);
+			}
 		}
 		put_cpu();
 		break;
@@ -798,7 +512,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 				/* set the selector to 0 to not confuse
 				   __switch_to */
 				loadsegment(fs, 0);
-				ret = checking_wrmsrl(MSR_FS_BASE, addr);
+				ret = wrmsrl_safe(MSR_FS_BASE, addr);
 			}
 		}
 		put_cpu();
@@ -825,8 +539,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 				rdmsrl(MSR_KERNEL_GS_BASE, base);
 			else
 				base = task->thread.gs;
-		}
-		else
+		} else
 			base = task->thread.gs;
 		ret = put_user(base, (unsigned long __user *)addr);
 		break;
@@ -845,15 +558,8 @@ long sys_arch_prctl(int code, unsigned long addr)
 	return do_arch_prctl(current, code, addr);
 }
 
-unsigned long arch_align_stack(unsigned long sp)
-{
-	if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
-		sp -= get_random_int() % 8192;
-	return sp & ~0xf;
-}
-
-unsigned long arch_randomize_brk(struct mm_struct *mm)
+unsigned long KSTK_ESP(struct task_struct *task)
 {
-	unsigned long range_end = mm->brk + 0x02000000;
-	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
+	return (test_tsk_thread_flag(task, TIF_IA32)) ?
+			(task_pt_regs(task)->sp) : ((task)->thread.usersp);
 }