Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
This commit is contained in:
Linus Torvalds
770
arch/x86_64/kernel/process.c
Normal file
770
arch/x86_64/kernel/process.c
Normal file
@@ -0,0 +1,770 @@
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/*
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* linux/arch/x86-64/kernel/process.c
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*
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* Copyright (C) 1995 Linus Torvalds
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*
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* Pentium III FXSR, SSE support
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* Gareth Hughes <gareth@valinux.com>, May 2000
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*
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* X86-64 port
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* Andi Kleen.
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*
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* $Id: process.c,v 1.38 2002/01/15 10:08:03 ak Exp $
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*/
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/*
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* This file handles the architecture-dependent parts of process handling..
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*/
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#include <stdarg.h>
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#include <linux/errno.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/elfcore.h>
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#include <linux/smp.h>
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#include <linux/slab.h>
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#include <linux/user.h>
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#include <linux/module.h>
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#include <linux/a.out.h>
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#include <linux/interrupt.h>
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#include <linux/delay.h>
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#include <linux/irq.h>
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#include <linux/ptrace.h>
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#include <linux/utsname.h>
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#include <linux/random.h>
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#include <asm/uaccess.h>
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#include <asm/pgtable.h>
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#include <asm/system.h>
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#include <asm/io.h>
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#include <asm/processor.h>
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#include <asm/i387.h>
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#include <asm/mmu_context.h>
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#include <asm/pda.h>
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#include <asm/prctl.h>
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#include <asm/kdebug.h>
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#include <asm/desc.h>
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#include <asm/proto.h>
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#include <asm/ia32.h>
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asmlinkage extern void ret_from_fork(void);
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unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED;
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static atomic_t hlt_counter = ATOMIC_INIT(0);
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unsigned long boot_option_idle_override = 0;
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EXPORT_SYMBOL(boot_option_idle_override);
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/*
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* Powermanagement idle function, if any..
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*/
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void (*pm_idle)(void);
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static DEFINE_PER_CPU(unsigned int, cpu_idle_state);
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void disable_hlt(void)
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{
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atomic_inc(&hlt_counter);
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}
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EXPORT_SYMBOL(disable_hlt);
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void enable_hlt(void)
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{
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atomic_dec(&hlt_counter);
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}
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EXPORT_SYMBOL(enable_hlt);
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/*
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* We use this if we don't have any better
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* idle routine..
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*/
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void default_idle(void)
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{
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if (!atomic_read(&hlt_counter)) {
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local_irq_disable();
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if (!need_resched())
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safe_halt();
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else
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local_irq_enable();
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}
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}
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/*
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* On SMP it's slightly faster (but much more power-consuming!)
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* to poll the ->need_resched flag instead of waiting for the
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* cross-CPU IPI to arrive. Use this option with caution.
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*/
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static void poll_idle (void)
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{
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int oldval;
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local_irq_enable();
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/*
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* Deal with another CPU just having chosen a thread to
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* run here:
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*/
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oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
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if (!oldval) {
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set_thread_flag(TIF_POLLING_NRFLAG);
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asm volatile(
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"2:"
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"testl %0,%1;"
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"rep; nop;"
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"je 2b;"
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: :
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"i" (_TIF_NEED_RESCHED),
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"m" (current_thread_info()->flags));
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} else {
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set_need_resched();
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}
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}
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void cpu_idle_wait(void)
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{
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unsigned int cpu, this_cpu = get_cpu();
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cpumask_t map;
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set_cpus_allowed(current, cpumask_of_cpu(this_cpu));
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put_cpu();
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cpus_clear(map);
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for_each_online_cpu(cpu) {
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per_cpu(cpu_idle_state, cpu) = 1;
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cpu_set(cpu, map);
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}
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__get_cpu_var(cpu_idle_state) = 0;
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wmb();
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do {
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ssleep(1);
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for_each_online_cpu(cpu) {
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if (cpu_isset(cpu, map) && !per_cpu(cpu_idle_state, cpu))
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cpu_clear(cpu, map);
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}
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cpus_and(map, map, cpu_online_map);
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} while (!cpus_empty(map));
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}
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EXPORT_SYMBOL_GPL(cpu_idle_wait);
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/*
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* The idle thread. There's no useful work to be
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* done, so just try to conserve power and have a
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* low exit latency (ie sit in a loop waiting for
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* somebody to say that they'd like to reschedule)
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*/
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void cpu_idle (void)
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{
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/* endless idle loop with no priority at all */
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while (1) {
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while (!need_resched()) {
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void (*idle)(void);
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if (__get_cpu_var(cpu_idle_state))
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__get_cpu_var(cpu_idle_state) = 0;
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rmb();
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idle = pm_idle;
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if (!idle)
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idle = default_idle;
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idle();
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}
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schedule();
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}
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}
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/*
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* This uses new MONITOR/MWAIT instructions on P4 processors with PNI,
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* which can obviate IPI to trigger checking of need_resched.
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* We execute MONITOR against need_resched and enter optimized wait state
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* through MWAIT. Whenever someone changes need_resched, we would be woken
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* up from MWAIT (without an IPI).
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*/
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static void mwait_idle(void)
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{
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local_irq_enable();
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if (!need_resched()) {
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set_thread_flag(TIF_POLLING_NRFLAG);
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do {
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__monitor((void *)¤t_thread_info()->flags, 0, 0);
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if (need_resched())
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break;
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__mwait(0, 0);
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} while (!need_resched());
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clear_thread_flag(TIF_POLLING_NRFLAG);
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}
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}
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void __init select_idle_routine(const struct cpuinfo_x86 *c)
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{
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static int printed;
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if (cpu_has(c, X86_FEATURE_MWAIT)) {
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/*
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* Skip, if setup has overridden idle.
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* One CPU supports mwait => All CPUs supports mwait
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*/
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if (!pm_idle) {
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if (!printed) {
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printk("using mwait in idle threads.\n");
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printed = 1;
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}
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pm_idle = mwait_idle;
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}
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}
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}
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static int __init idle_setup (char *str)
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{
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if (!strncmp(str, "poll", 4)) {
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printk("using polling idle threads.\n");
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pm_idle = poll_idle;
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}
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boot_option_idle_override = 1;
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return 1;
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}
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__setup("idle=", idle_setup);
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/* Prints also some state that isn't saved in the pt_regs */
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void __show_regs(struct pt_regs * regs)
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{
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unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs;
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unsigned int fsindex,gsindex;
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unsigned int ds,cs,es;
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printk("\n");
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print_modules();
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printk("Pid: %d, comm: %.20s %s %s\n",
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current->pid, current->comm, print_tainted(), system_utsname.release);
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printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip);
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printk_address(regs->rip);
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printk("\nRSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp, regs->eflags);
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printk("RAX: %016lx RBX: %016lx RCX: %016lx\n",
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regs->rax, regs->rbx, regs->rcx);
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printk("RDX: %016lx RSI: %016lx RDI: %016lx\n",
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regs->rdx, regs->rsi, regs->rdi);
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printk("RBP: %016lx R08: %016lx R09: %016lx\n",
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regs->rbp, regs->r8, regs->r9);
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printk("R10: %016lx R11: %016lx R12: %016lx\n",
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regs->r10, regs->r11, regs->r12);
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printk("R13: %016lx R14: %016lx R15: %016lx\n",
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regs->r13, regs->r14, regs->r15);
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asm("movl %%ds,%0" : "=r" (ds));
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asm("movl %%cs,%0" : "=r" (cs));
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asm("movl %%es,%0" : "=r" (es));
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asm("movl %%fs,%0" : "=r" (fsindex));
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asm("movl %%gs,%0" : "=r" (gsindex));
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rdmsrl(MSR_FS_BASE, fs);
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rdmsrl(MSR_GS_BASE, gs);
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rdmsrl(MSR_KERNEL_GS_BASE, shadowgs);
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asm("movq %%cr0, %0": "=r" (cr0));
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asm("movq %%cr2, %0": "=r" (cr2));
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asm("movq %%cr3, %0": "=r" (cr3));
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asm("movq %%cr4, %0": "=r" (cr4));
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printk("FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
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fs,fsindex,gs,gsindex,shadowgs);
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printk("CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds, es, cr0);
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printk("CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3, cr4);
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}
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void show_regs(struct pt_regs *regs)
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{
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__show_regs(regs);
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show_trace(®s->rsp);
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}
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/*
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* Free current thread data structures etc..
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*/
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void exit_thread(void)
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{
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struct task_struct *me = current;
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struct thread_struct *t = &me->thread;
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if (me->thread.io_bitmap_ptr) {
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struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
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kfree(t->io_bitmap_ptr);
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t->io_bitmap_ptr = NULL;
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/*
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* Careful, clear this in the TSS too:
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*/
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memset(tss->io_bitmap, 0xff, t->io_bitmap_max);
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t->io_bitmap_max = 0;
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put_cpu();
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}
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}
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void flush_thread(void)
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{
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struct task_struct *tsk = current;
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struct thread_info *t = current_thread_info();
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if (t->flags & _TIF_ABI_PENDING)
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t->flags ^= (_TIF_ABI_PENDING | _TIF_IA32);
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||||
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tsk->thread.debugreg0 = 0;
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tsk->thread.debugreg1 = 0;
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tsk->thread.debugreg2 = 0;
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tsk->thread.debugreg3 = 0;
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tsk->thread.debugreg6 = 0;
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tsk->thread.debugreg7 = 0;
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memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
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/*
|
||||
* Forget coprocessor state..
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||||
*/
|
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clear_fpu(tsk);
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clear_used_math();
|
||||
}
|
||||
|
||||
void release_thread(struct task_struct *dead_task)
|
||||
{
|
||||
if (dead_task->mm) {
|
||||
if (dead_task->mm->context.size) {
|
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printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
|
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dead_task->comm,
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dead_task->mm->context.ldt,
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dead_task->mm->context.size);
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BUG();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr)
|
||||
{
|
||||
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;
|
||||
desc += tls;
|
||||
desc->a = LDT_entry_a(&ud);
|
||||
desc->b = LDT_entry_b(&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);
|
||||
}
|
||||
|
||||
/*
|
||||
* 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 rsp,
|
||||
unsigned long unused,
|
||||
struct task_struct * p, struct pt_regs * regs)
|
||||
{
|
||||
int err;
|
||||
struct pt_regs * childregs;
|
||||
struct task_struct *me = current;
|
||||
|
||||
childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
|
||||
|
||||
*childregs = *regs;
|
||||
|
||||
childregs->rax = 0;
|
||||
childregs->rsp = rsp;
|
||||
if (rsp == ~0UL) {
|
||||
childregs->rsp = (unsigned long)childregs;
|
||||
}
|
||||
|
||||
p->thread.rsp = (unsigned long) childregs;
|
||||
p->thread.rsp0 = (unsigned long) (childregs+1);
|
||||
p->thread.userrsp = me->thread.userrsp;
|
||||
|
||||
set_ti_thread_flag(p->thread_info, TIF_FORK);
|
||||
|
||||
p->thread.fs = me->thread.fs;
|
||||
p->thread.gs = me->thread.gs;
|
||||
|
||||
asm("movl %%gs,%0" : "=m" (p->thread.gsindex));
|
||||
asm("movl %%fs,%0" : "=m" (p->thread.fsindex));
|
||||
asm("movl %%es,%0" : "=m" (p->thread.es));
|
||||
asm("movl %%ds,%0" : "=m" (p->thread.ds));
|
||||
|
||||
if (unlikely(me->thread.io_bitmap_ptr != NULL)) {
|
||||
p->thread.io_bitmap_ptr = kmalloc(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 a new TLS for the child thread?
|
||||
*/
|
||||
if (clone_flags & CLONE_SETTLS) {
|
||||
#ifdef CONFIG_IA32_EMULATION
|
||||
if (test_thread_flag(TIF_IA32))
|
||||
err = ia32_child_tls(p, childregs);
|
||||
else
|
||||
#endif
|
||||
err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8);
|
||||
if (err)
|
||||
goto out;
|
||||
}
|
||||
err = 0;
|
||||
out:
|
||||
if (err && p->thread.io_bitmap_ptr) {
|
||||
kfree(p->thread.io_bitmap_ptr);
|
||||
p->thread.io_bitmap_max = 0;
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
/*
|
||||
* This special macro can be used to load a debugging register
|
||||
*/
|
||||
#define loaddebug(thread,r) set_debug(thread->debugreg ## r, r)
|
||||
|
||||
/*
|
||||
* switch_to(x,y) should switch tasks from x to y.
|
||||
*
|
||||
* 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
|
||||
*/
|
||||
struct task_struct *__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();
|
||||
struct tss_struct *tss = &per_cpu(init_tss, cpu);
|
||||
|
||||
unlazy_fpu(prev_p);
|
||||
|
||||
/*
|
||||
* Reload esp0, LDT and the page table pointer:
|
||||
*/
|
||||
tss->rsp0 = next->rsp0;
|
||||
|
||||
/*
|
||||
* Switch DS and ES.
|
||||
* This won't pick up thread selector changes, but I guess that is ok.
|
||||
*/
|
||||
asm volatile("movl %%es,%0" : "=m" (prev->es));
|
||||
if (unlikely(next->es | prev->es))
|
||||
loadsegment(es, next->es);
|
||||
|
||||
asm volatile ("movl %%ds,%0" : "=m" (prev->ds));
|
||||
if (unlikely(next->ds | prev->ds))
|
||||
loadsegment(ds, next->ds);
|
||||
|
||||
load_TLS(next, cpu);
|
||||
|
||||
/*
|
||||
* Switch FS and GS.
|
||||
*/
|
||||
{
|
||||
unsigned fsindex;
|
||||
asm volatile("movl %%fs,%0" : "=r" (fsindex));
|
||||
/* segment register != 0 always requires a reload.
|
||||
also reload when it has changed.
|
||||
when prev process used 64bit base always reload
|
||||
to avoid an information leak. */
|
||||
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;
|
||||
}
|
||||
/* when next process has a 64bit base use it */
|
||||
if (next->fs)
|
||||
wrmsrl(MSR_FS_BASE, next->fs);
|
||||
prev->fsindex = fsindex;
|
||||
}
|
||||
{
|
||||
unsigned gsindex;
|
||||
asm volatile("movl %%gs,%0" : "=r" (gsindex));
|
||||
if (unlikely(gsindex | next->gsindex | prev->gs)) {
|
||||
load_gs_index(next->gsindex);
|
||||
if (gsindex)
|
||||
prev->gs = 0;
|
||||
}
|
||||
if (next->gs)
|
||||
wrmsrl(MSR_KERNEL_GS_BASE, next->gs);
|
||||
prev->gsindex = gsindex;
|
||||
}
|
||||
|
||||
/*
|
||||
* Switch the PDA context.
|
||||
*/
|
||||
prev->userrsp = read_pda(oldrsp);
|
||||
write_pda(oldrsp, next->userrsp);
|
||||
write_pda(pcurrent, next_p);
|
||||
write_pda(kernelstack, (unsigned long)next_p->thread_info + THREAD_SIZE - PDA_STACKOFFSET);
|
||||
|
||||
/*
|
||||
* Now maybe reload the debug registers
|
||||
*/
|
||||
if (unlikely(next->debugreg7)) {
|
||||
loaddebug(next, 0);
|
||||
loaddebug(next, 1);
|
||||
loaddebug(next, 2);
|
||||
loaddebug(next, 3);
|
||||
/* no 4 and 5 */
|
||||
loaddebug(next, 6);
|
||||
loaddebug(next, 7);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Handle the IO bitmap
|
||||
*/
|
||||
if (unlikely(prev->io_bitmap_ptr || next->io_bitmap_ptr)) {
|
||||
if (next->io_bitmap_ptr)
|
||||
/*
|
||||
* 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 {
|
||||
/*
|
||||
* Clear any possible leftover bits:
|
||||
*/
|
||||
memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
|
||||
}
|
||||
}
|
||||
|
||||
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, ®s);
|
||||
if (error == 0) {
|
||||
task_lock(current);
|
||||
current->ptrace &= ~PT_DTRACE;
|
||||
task_unlock(current);
|
||||
}
|
||||
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);
|
||||
|
||||
/* 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. */
|
||||
current->personality &= ~READ_IMPLIES_EXEC;
|
||||
}
|
||||
|
||||
asmlinkage long sys_fork(struct pt_regs *regs)
|
||||
{
|
||||
return do_fork(SIGCHLD, regs->rsp, 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)
|
||||
{
|
||||
if (!newsp)
|
||||
newsp = regs->rsp;
|
||||
return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
|
||||
}
|
||||
|
||||
/*
|
||||
* 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->rsp, regs, 0,
|
||||
NULL, NULL);
|
||||
}
|
||||
|
||||
unsigned long get_wchan(struct task_struct *p)
|
||||
{
|
||||
unsigned long stack;
|
||||
u64 fp,rip;
|
||||
int count = 0;
|
||||
|
||||
if (!p || p == current || p->state==TASK_RUNNING)
|
||||
return 0;
|
||||
stack = (unsigned long)p->thread_info;
|
||||
if (p->thread.rsp < stack || p->thread.rsp > stack+THREAD_SIZE)
|
||||
return 0;
|
||||
fp = *(u64 *)(p->thread.rsp);
|
||||
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;
|
||||
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 doit = task == current;
|
||||
int cpu;
|
||||
|
||||
switch (code) {
|
||||
case ARCH_SET_GS:
|
||||
if (addr >= TASK_SIZE)
|
||||
return -EPERM;
|
||||
cpu = get_cpu();
|
||||
/* handle small bases via the GDT because that's faster to
|
||||
switch. */
|
||||
if (addr <= 0xffffffff) {
|
||||
set_32bit_tls(task, GS_TLS, addr);
|
||||
if (doit) {
|
||||
load_TLS(&task->thread, cpu);
|
||||
load_gs_index(GS_TLS_SEL);
|
||||
}
|
||||
task->thread.gsindex = GS_TLS_SEL;
|
||||
task->thread.gs = 0;
|
||||
} else {
|
||||
task->thread.gsindex = 0;
|
||||
task->thread.gs = addr;
|
||||
if (doit) {
|
||||
load_gs_index(0);
|
||||
ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr);
|
||||
}
|
||||
}
|
||||
put_cpu();
|
||||
break;
|
||||
case ARCH_SET_FS:
|
||||
/* Not strictly needed for fs, but do it for symmetry
|
||||
with gs */
|
||||
if (addr >= TASK_SIZE)
|
||||
return -EPERM;
|
||||
cpu = get_cpu();
|
||||
/* handle small bases via the GDT because that's faster to
|
||||
switch. */
|
||||
if (addr <= 0xffffffff) {
|
||||
set_32bit_tls(task, FS_TLS, addr);
|
||||
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 {
|
||||
task->thread.fsindex = 0;
|
||||
task->thread.fs = addr;
|
||||
if (doit) {
|
||||
/* set the selector to 0 to not confuse
|
||||
__switch_to */
|
||||
asm volatile("movl %0,%%fs" :: "r" (0));
|
||||
ret = checking_wrmsrl(MSR_FS_BASE, addr);
|
||||
}
|
||||
}
|
||||
put_cpu();
|
||||
break;
|
||||
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;
|
||||
}
|
||||
case ARCH_GET_GS: {
|
||||
unsigned long base;
|
||||
if (task->thread.gsindex == GS_TLS_SEL)
|
||||
base = read_32bit_tls(task, GS_TLS);
|
||||
else if (doit) {
|
||||
rdmsrl(MSR_KERNEL_GS_BASE, base);
|
||||
} else
|
||||
base = task->thread.gs;
|
||||
ret = put_user(base, (unsigned long __user *)addr);
|
||||
break;
|
||||
}
|
||||
|
||||
default:
|
||||
ret = -EINVAL;
|
||||
break;
|
||||
}
|
||||
|
||||
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 = (struct pt_regs *)(tsk->thread.rsp0);
|
||||
--pp;
|
||||
|
||||
ptregs = *pp;
|
||||
ptregs.cs &= 0xffff;
|
||||
ptregs.ss &= 0xffff;
|
||||
|
||||
elf_core_copy_regs(regs, &ptregs);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
unsigned long arch_align_stack(unsigned long sp)
|
||||
{
|
||||
if (randomize_va_space)
|
||||
sp -= get_random_int() % 8192;
|
||||
return sp & ~0xf;
|
||||
}
|
||||
Reference in New Issue
Block a user