![Len Brown](/assets/img/avatar_default.png)
Conflicts: MAINTAINERS arch/x86/kernel/acpi/boot.c arch/x86/kernel/acpi/sleep.c drivers/acpi/Kconfig drivers/pnp/Makefile drivers/pnp/quirks.c Signed-off-by: Len Brown <len.brown@intel.com>
876 lines
21 KiB
C
876 lines
21 KiB
C
/*
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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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* CPU hotplug support - ashok.raj@intel.com
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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/cpu.h>
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#include <linux/errno.h>
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#include <linux/sched.h>
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#include <linux/fs.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/interrupt.h>
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#include <linux/utsname.h>
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#include <linux/delay.h>
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#include <linux/module.h>
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#include <linux/ptrace.h>
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#include <linux/random.h>
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#include <linux/notifier.h>
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#include <linux/kprobes.h>
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#include <linux/kdebug.h>
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#include <linux/tick.h>
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#include <linux/prctl.h>
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#include <linux/uaccess.h>
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#include <linux/io.h>
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#include <asm/pgtable.h>
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#include <asm/system.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/desc.h>
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#include <asm/proto.h>
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#include <asm/ia32.h>
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#include <asm/idle.h>
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#include <asm/syscalls.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_NOTIFIER_HEAD(idle_notifier);
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void idle_notifier_register(struct notifier_block *n)
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{
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atomic_notifier_chain_register(&idle_notifier, n);
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}
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EXPORT_SYMBOL_GPL(idle_notifier_register);
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void idle_notifier_unregister(struct notifier_block *n)
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{
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atomic_notifier_chain_unregister(&idle_notifier, n);
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}
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EXPORT_SYMBOL_GPL(idle_notifier_unregister);
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void enter_idle(void)
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{
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write_pda(isidle, 1);
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atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
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}
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static void __exit_idle(void)
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{
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if (test_and_clear_bit_pda(0, isidle) == 0)
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return;
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atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
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}
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/* Called from interrupts to signify idle end */
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void exit_idle(void)
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{
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/* idle loop has pid 0 */
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if (current->pid)
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return;
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__exit_idle();
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}
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#ifndef CONFIG_SMP
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static inline void play_dead(void)
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{
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BUG();
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}
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#endif
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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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current_thread_info()->status |= TS_POLLING;
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/* endless idle loop with no priority at all */
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while (1) {
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tick_nohz_stop_sched_tick(1);
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while (!need_resched()) {
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rmb();
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if (cpu_is_offline(smp_processor_id()))
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play_dead();
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/*
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* Idle routines should keep interrupts disabled
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* from here on, until they go to idle.
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* Otherwise, idle callbacks can misfire.
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*/
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local_irq_disable();
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enter_idle();
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/* Don't trace irqs off for idle */
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stop_critical_timings();
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pm_idle();
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start_critical_timings();
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/* In many cases the interrupt that ended idle
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has already called exit_idle. But some idle
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loops can be woken up without interrupt. */
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__exit_idle();
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}
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tick_nohz_restart_sched_tick();
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preempt_enable_no_resched();
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schedule();
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preempt_disable();
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}
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}
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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, int all)
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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 long d0, d1, d2, d3, d6, d7;
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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(KERN_INFO "Pid: %d, comm: %.20s %s %s %.*s\n",
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current->pid, current->comm, print_tainted(),
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init_utsname()->release,
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(int)strcspn(init_utsname()->version, " "),
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init_utsname()->version);
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printk(KERN_INFO "RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip);
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printk_address(regs->ip, 1);
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printk(KERN_INFO "RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss,
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regs->sp, regs->flags);
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printk(KERN_INFO "RAX: %016lx RBX: %016lx RCX: %016lx\n",
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regs->ax, regs->bx, regs->cx);
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printk(KERN_INFO "RDX: %016lx RSI: %016lx RDI: %016lx\n",
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regs->dx, regs->si, regs->di);
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printk(KERN_INFO "RBP: %016lx R08: %016lx R09: %016lx\n",
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regs->bp, regs->r8, regs->r9);
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printk(KERN_INFO "R10: %016lx R11: %016lx R12: %016lx\n",
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regs->r10, regs->r11, regs->r12);
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printk(KERN_INFO "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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if (!all)
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return;
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cr0 = read_cr0();
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cr2 = read_cr2();
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cr3 = read_cr3();
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cr4 = read_cr4();
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printk(KERN_INFO "FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
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fs, fsindex, gs, gsindex, shadowgs);
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printk(KERN_INFO "CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds,
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es, cr0);
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printk(KERN_INFO "CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3,
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cr4);
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get_debugreg(d0, 0);
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get_debugreg(d1, 1);
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get_debugreg(d2, 2);
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printk(KERN_INFO "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2);
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get_debugreg(d3, 3);
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get_debugreg(d6, 6);
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get_debugreg(d7, 7);
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printk(KERN_INFO "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7);
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}
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void show_regs(struct pt_regs *regs)
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{
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printk(KERN_INFO "CPU %d:", smp_processor_id());
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__show_regs(regs, 1);
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show_trace(NULL, regs, (void *)(regs + 1), regs->bp);
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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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clear_thread_flag(TIF_IO_BITMAP);
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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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#ifdef CONFIG_X86_DS
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/* Free any DS contexts that have not been properly released. */
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if (unlikely(t->ds_ctx)) {
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/* we clear debugctl to make sure DS is not used. */
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update_debugctlmsr(0);
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ds_free(t->ds_ctx);
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}
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#endif /* CONFIG_X86_DS */
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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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if (test_tsk_thread_flag(tsk, TIF_ABI_PENDING)) {
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clear_tsk_thread_flag(tsk, TIF_ABI_PENDING);
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if (test_tsk_thread_flag(tsk, TIF_IA32)) {
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clear_tsk_thread_flag(tsk, TIF_IA32);
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} else {
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set_tsk_thread_flag(tsk, TIF_IA32);
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current_thread_info()->status |= TS_COMPAT;
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}
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}
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clear_tsk_thread_flag(tsk, TIF_DEBUG);
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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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/*
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* Forget coprocessor state..
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*/
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tsk->fpu_counter = 0;
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clear_fpu(tsk);
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clear_used_math();
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}
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void release_thread(struct task_struct *dead_task)
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{
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if (dead_task->mm) {
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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();
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}
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}
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}
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static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr)
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{
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struct user_desc ud = {
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.base_addr = addr,
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.limit = 0xfffff,
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.seg_32bit = 1,
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.limit_in_pages = 1,
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.useable = 1,
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};
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struct desc_struct *desc = t->thread.tls_array;
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desc += tls;
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fill_ldt(desc, &ud);
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}
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static inline u32 read_32bit_tls(struct task_struct *t, int tls)
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{
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return get_desc_base(&t->thread.tls_array[tls]);
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}
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/*
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* This gets called before we allocate a new thread and copy
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* the current task into it.
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*/
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void prepare_to_copy(struct task_struct *tsk)
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{
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unlazy_fpu(tsk);
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}
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int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
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unsigned long unused,
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struct task_struct *p, struct pt_regs *regs)
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{
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int err;
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struct pt_regs *childregs;
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struct task_struct *me = current;
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childregs = ((struct pt_regs *)
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(THREAD_SIZE + task_stack_page(p))) - 1;
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*childregs = *regs;
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childregs->ax = 0;
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childregs->sp = sp;
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if (sp == ~0UL)
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childregs->sp = (unsigned long)childregs;
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p->thread.sp = (unsigned long) childregs;
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p->thread.sp0 = (unsigned long) (childregs+1);
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p->thread.usersp = me->thread.usersp;
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set_tsk_thread_flag(p, TIF_FORK);
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p->thread.fs = me->thread.fs;
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p->thread.gs = me->thread.gs;
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savesegment(gs, p->thread.gsindex);
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savesegment(fs, p->thread.fsindex);
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savesegment(es, p->thread.es);
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savesegment(ds, p->thread.ds);
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if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
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p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
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if (!p->thread.io_bitmap_ptr) {
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p->thread.io_bitmap_max = 0;
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return -ENOMEM;
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}
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memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr,
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IO_BITMAP_BYTES);
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set_tsk_thread_flag(p, TIF_IO_BITMAP);
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}
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/*
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* Set a new TLS for the child thread?
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*/
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if (clone_flags & CLONE_SETTLS) {
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#ifdef CONFIG_IA32_EMULATION
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if (test_thread_flag(TIF_IA32))
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err = do_set_thread_area(p, -1,
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(struct user_desc __user *)childregs->si, 0);
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else
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#endif
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err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8);
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if (err)
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goto out;
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}
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err = 0;
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out:
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if (err && p->thread.io_bitmap_ptr) {
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kfree(p->thread.io_bitmap_ptr);
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p->thread.io_bitmap_max = 0;
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}
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return err;
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}
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void
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start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
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{
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loadsegment(fs, 0);
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loadsegment(es, 0);
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loadsegment(ds, 0);
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load_gs_index(0);
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regs->ip = new_ip;
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regs->sp = new_sp;
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write_pda(oldrsp, new_sp);
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regs->cs = __USER_CS;
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regs->ss = __USER_DS;
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regs->flags = 0x200;
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set_fs(USER_DS);
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/*
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* Free the old FP and other extended state
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*/
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free_thread_xstate(current);
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}
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EXPORT_SYMBOL_GPL(start_thread);
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static void hard_disable_TSC(void)
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{
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write_cr4(read_cr4() | X86_CR4_TSD);
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}
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void disable_TSC(void)
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{
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preempt_disable();
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if (!test_and_set_thread_flag(TIF_NOTSC))
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/*
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* Must flip the CPU state synchronously with
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* TIF_NOTSC in the current running context.
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*/
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hard_disable_TSC();
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preempt_enable();
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}
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static void hard_enable_TSC(void)
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{
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write_cr4(read_cr4() & ~X86_CR4_TSD);
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}
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static void enable_TSC(void)
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{
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preempt_disable();
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if (test_and_clear_thread_flag(TIF_NOTSC))
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/*
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* Must flip the CPU state synchronously with
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* TIF_NOTSC in the current running context.
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*/
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hard_enable_TSC();
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preempt_enable();
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}
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int get_tsc_mode(unsigned long adr)
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{
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unsigned int val;
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if (test_thread_flag(TIF_NOTSC))
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val = PR_TSC_SIGSEGV;
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else
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val = PR_TSC_ENABLE;
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return put_user(val, (unsigned int __user *)adr);
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}
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int set_tsc_mode(unsigned int val)
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{
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if (val == PR_TSC_SIGSEGV)
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disable_TSC();
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else if (val == PR_TSC_ENABLE)
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enable_TSC();
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else
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return -EINVAL;
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return 0;
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}
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/*
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* This special macro can be used to load a debugging register
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*/
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#define loaddebug(thread, r) set_debugreg(thread->debugreg ## r, r)
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static inline void __switch_to_xtra(struct task_struct *prev_p,
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struct task_struct *next_p,
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struct tss_struct *tss)
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{
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struct thread_struct *prev, *next;
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unsigned long debugctl;
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prev = &prev_p->thread,
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next = &next_p->thread;
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debugctl = prev->debugctlmsr;
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#ifdef CONFIG_X86_DS
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{
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unsigned long ds_prev = 0, ds_next = 0;
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if (prev->ds_ctx)
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ds_prev = (unsigned long)prev->ds_ctx->ds;
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if (next->ds_ctx)
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ds_next = (unsigned long)next->ds_ctx->ds;
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if (ds_next != ds_prev) {
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/*
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* We clear debugctl to make sure DS
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* is not in use when we change it:
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*/
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debugctl = 0;
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update_debugctlmsr(0);
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wrmsrl(MSR_IA32_DS_AREA, ds_next);
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}
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}
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#endif /* CONFIG_X86_DS */
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if (next->debugctlmsr != debugctl)
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update_debugctlmsr(next->debugctlmsr);
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if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
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loaddebug(next, 0);
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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 CONFIG_X86_PTRACE_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 /* CONFIG_X86_PTRACE_BTS */
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
*
|
|
* Kprobes not supported here. Set the probe on schedule instead.
|
|
*/
|
|
struct task_struct *
|
|
__switch_to(struct task_struct *prev_p, struct task_struct *next_p)
|
|
{
|
|
struct thread_struct *prev = &prev_p->thread;
|
|
struct thread_struct *next = &next_p->thread;
|
|
int cpu = smp_processor_id();
|
|
struct tss_struct *tss = &per_cpu(init_tss, cpu);
|
|
unsigned fsindex, gsindex;
|
|
|
|
/* we're going to use this soon, after a few expensive things */
|
|
if (next_p->fpu_counter > 5)
|
|
prefetch(next->xstate);
|
|
|
|
/*
|
|
* 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);
|
|
|
|
savesegment(ds, prev->ds);
|
|
if (unlikely(next->ds | prev->ds))
|
|
loadsegment(ds, next->ds);
|
|
|
|
|
|
/* We must save %fs and %gs before load_TLS() because
|
|
* %fs and %gs may be cleared by load_TLS().
|
|
*
|
|
* (e.g. xen_load_tls())
|
|
*/
|
|
savesegment(fs, fsindex);
|
|
savesegment(gs, gsindex);
|
|
|
|
load_TLS(next, cpu);
|
|
|
|
/*
|
|
* Leave lazy mode, flushing any hypercalls made here.
|
|
* This must be done before restoring TLS segments so
|
|
* the GDT and LDT are properly updated, and must be
|
|
* done before math_state_restore, so the TS bit is up
|
|
* to date.
|
|
*/
|
|
arch_leave_lazy_cpu_mode();
|
|
|
|
/*
|
|
* Switch FS and GS.
|
|
*
|
|
* 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;
|
|
|
|
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;
|
|
|
|
/* Must be after DS reload */
|
|
unlazy_fpu(prev_p);
|
|
|
|
/*
|
|
* Switch the PDA and FPU contexts.
|
|
*/
|
|
prev->usersp = read_pda(oldrsp);
|
|
write_pda(oldrsp, next->usersp);
|
|
write_pda(pcurrent, 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
|
|
*/
|
|
BUILD_BUG_ON(offsetof(struct x8664_pda, stack_canary) != 40);
|
|
#endif
|
|
|
|
/*
|
|
* Now maybe reload the debug registers and handle I/O bitmaps
|
|
*/
|
|
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
|
|
* 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);
|
|
|
|
/* 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->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)
|
|
{
|
|
if (!newsp)
|
|
newsp = regs->sp;
|
|
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->sp, regs, 0,
|
|
NULL, NULL);
|
|
}
|
|
|
|
unsigned long get_wchan(struct task_struct *p)
|
|
{
|
|
unsigned long stack;
|
|
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.sp < stack || p->thread.sp >= stack+THREAD_SIZE)
|
|
return 0;
|
|
fp = *(u64 *)(p->thread.sp);
|
|
do {
|
|
if (fp < (unsigned long)stack ||
|
|
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);
|
|
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_OF(task))
|
|
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_OF(task))
|
|
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);
|
|
loadsegment(fs, 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 */
|
|
loadsegment(fs, 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;
|
|
unsigned gsindex;
|
|
if (task->thread.gsindex == GS_TLS_SEL)
|
|
base = read_32bit_tls(task, GS_TLS);
|
|
else if (doit) {
|
|
savesegment(gs, gsindex);
|
|
if (gsindex)
|
|
rdmsrl(MSR_KERNEL_GS_BASE, base);
|
|
else
|
|
base = task->thread.gs;
|
|
} 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);
|
|
}
|
|
|
|
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 range_end = mm->brk + 0x02000000;
|
|
return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
|
|
}
|