X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fprocess_64.c;h=fbb321d53d3495990c946ecbfa51f2ddfdc2ad19;hb=855caa37b9b61c1ccfeb91a2bc04d90bfc5e4525;hp=efbb1a2eab97bdf214804a5f2a83c8b133de976d;hpb=65ea5b0349903585bfed9720fa06f5edb4f1cd25;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index efbb1a2e..fbb321d 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -3,7 +3,7 @@ * * Pentium III FXSR, SSE support * Gareth Hughes , May 2000 - * + * * X86-64 port * Andi Kleen. * @@ -19,29 +19,30 @@ #include #include #include +#include #include #include -#include #include #include #include #include -#include -#include #include +#include #include +#include #include -#include #include #include #include #include #include +#include +#include +#include +#include -#include #include #include -#include #include #include #include @@ -51,27 +52,25 @@ #include #include #include +#include asmlinkage extern void ret_from_fork(void); unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED; -unsigned long boot_option_idle_override = 0; -EXPORT_SYMBOL(boot_option_idle_override); - -/* - * Powermanagement idle function, if any.. - */ -void (*pm_idle)(void); -EXPORT_SYMBOL(pm_idle); -static DEFINE_PER_CPU(unsigned int, cpu_idle_state); - static ATOMIC_NOTIFIER_HEAD(idle_notifier); void idle_notifier_register(struct notifier_block *n) { atomic_notifier_chain_register(&idle_notifier, n); } +EXPORT_SYMBOL_GPL(idle_notifier_register); + +void idle_notifier_unregister(struct notifier_block *n) +{ + atomic_notifier_chain_unregister(&idle_notifier, n); +} +EXPORT_SYMBOL_GPL(idle_notifier_unregister); void enter_idle(void) { @@ -95,111 +94,12 @@ void exit_idle(void) __exit_idle(); } -/* - * We use this if we don't have any better - * idle routine.. - */ -static void default_idle(void) -{ - current_thread_info()->status &= ~TS_POLLING; - /* - * TS_POLLING-cleared state must be visible before we - * test NEED_RESCHED: - */ - smp_mb(); - local_irq_disable(); - if (!need_resched()) { - ktime_t t0, t1; - u64 t0n, t1n; - - t0 = ktime_get(); - t0n = ktime_to_ns(t0); - safe_halt(); /* enables interrupts racelessly */ - local_irq_disable(); - t1 = ktime_get(); - t1n = ktime_to_ns(t1); - sched_clock_idle_wakeup_event(t1n - t0n); - } - local_irq_enable(); - current_thread_info()->status |= TS_POLLING; -} - -/* - * On SMP it's slightly faster (but much more power-consuming!) - * to poll the ->need_resched flag instead of waiting for the - * cross-CPU IPI to arrive. Use this option with caution. - */ -static void poll_idle (void) -{ - local_irq_enable(); - cpu_relax(); -} - -static void do_nothing(void *unused) -{ -} - -void cpu_idle_wait(void) -{ - unsigned int cpu, this_cpu = get_cpu(); - cpumask_t map, tmp = current->cpus_allowed; - - set_cpus_allowed(current, cpumask_of_cpu(this_cpu)); - put_cpu(); - - cpus_clear(map); - for_each_online_cpu(cpu) { - per_cpu(cpu_idle_state, cpu) = 1; - cpu_set(cpu, map); - } - - __get_cpu_var(cpu_idle_state) = 0; - - wmb(); - do { - ssleep(1); - for_each_online_cpu(cpu) { - if (cpu_isset(cpu, map) && - !per_cpu(cpu_idle_state, cpu)) - cpu_clear(cpu, map); - } - cpus_and(map, map, cpu_online_map); - /* - * We waited 1 sec, if a CPU still did not call idle - * it may be because it is in idle and not waking up - * because it has nothing to do. - * Give all the remaining CPUS a kick. - */ - smp_call_function_mask(map, do_nothing, 0, 0); - } while (!cpus_empty(map)); - - set_cpus_allowed(current, tmp); -} -EXPORT_SYMBOL_GPL(cpu_idle_wait); - -#ifdef CONFIG_HOTPLUG_CPU -DECLARE_PER_CPU(int, cpu_state); - -#include -/* We halt the CPU with physical CPU hotplug */ -static inline void play_dead(void) -{ - idle_task_exit(); - wbinvd(); - mb(); - /* Ack it */ - __get_cpu_var(cpu_state) = CPU_DEAD; - - local_irq_disable(); - while (1) - halt(); -} -#else +#ifndef CONFIG_SMP static inline void play_dead(void) { BUG(); } -#endif /* CONFIG_HOTPLUG_CPU */ +#endif /* * The idle thread. There's no useful work to be @@ -212,18 +112,11 @@ 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()) { - void (*idle)(void); - - if (__get_cpu_var(cpu_idle_state)) - __get_cpu_var(cpu_idle_state) = 0; - - tick_nohz_stop_sched_tick(); rmb(); - idle = pm_idle; - if (!idle) - idle = default_idle; + if (cpu_is_offline(smp_processor_id())) play_dead(); /* @@ -233,7 +126,10 @@ void cpu_idle(void) */ local_irq_disable(); enter_idle(); - 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. */ @@ -247,139 +143,76 @@ void cpu_idle(void) } } -/* - * This uses new MONITOR/MWAIT instructions on P4 processors with PNI, - * which can obviate IPI to trigger checking of need_resched. - * We execute MONITOR against need_resched and enter optimized wait state - * through MWAIT. Whenever someone changes need_resched, we would be woken - * up from MWAIT (without an IPI). - * - * New with Core Duo processors, MWAIT can take some hints based on CPU - * capability. - */ -void mwait_idle_with_hints(unsigned long ax, unsigned long cx) -{ - if (!need_resched()) { - __monitor((void *)¤t_thread_info()->flags, 0, 0); - smp_mb(); - if (!need_resched()) - __mwait(ax, cx); - } -} - -/* Default MONITOR/MWAIT with no hints, used for default C1 state */ -static void mwait_idle(void) -{ - if (!need_resched()) { - __monitor((void *)¤t_thread_info()->flags, 0, 0); - smp_mb(); - if (!need_resched()) - __sti_mwait(0, 0); - else - local_irq_enable(); - } else { - local_irq_enable(); - } -} - -void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) -{ - static int printed; - if (cpu_has(c, X86_FEATURE_MWAIT)) { - /* - * Skip, if setup has overridden idle. - * One CPU supports mwait => All CPUs supports mwait - */ - if (!pm_idle) { - if (!printed) { - printk(KERN_INFO "using mwait in idle threads.\n"); - printed = 1; - } - pm_idle = mwait_idle; - } - } -} - -static int __init idle_setup (char *str) -{ - if (!strcmp(str, "poll")) { - printk("using polling idle threads.\n"); - pm_idle = poll_idle; - } else if (!strcmp(str, "mwait")) - force_mwait = 1; - else - return -1; - - boot_option_idle_override = 1; - return 0; -} -early_param("idle", idle_setup); - -/* Prints also some state that isn't saved in the pt_regs */ -void __show_regs(struct pt_regs * regs) +/* Prints also some state that isn't saved in the pt_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; + unsigned int fsindex, gsindex; + unsigned int ds, cs, es; printk("\n"); print_modules(); - printk("Pid: %d, comm: %.20s %s %s %.*s\n", + printk(KERN_INFO "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); - printk("RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->sp, - regs->flags); - printk("RAX: %016lx RBX: %016lx RCX: %016lx\n", + printk(KERN_INFO "RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip); + printk_address(regs->ip, 1); + printk(KERN_INFO "RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, + regs->sp, regs->flags); + printk(KERN_INFO "RAX: %016lx RBX: %016lx RCX: %016lx\n", regs->ax, regs->bx, regs->cx); - printk("RDX: %016lx RSI: %016lx RDI: %016lx\n", + printk(KERN_INFO "RDX: %016lx RSI: %016lx RDI: %016lx\n", regs->dx, regs->si, regs->di); - printk("RBP: %016lx R08: %016lx R09: %016lx\n", + printk(KERN_INFO "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_INFO "R10: %016lx R11: %016lx R12: %016lx\n", + regs->r10, regs->r11, regs->r12); + printk(KERN_INFO "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_INFO "FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", + fs, fsindex, gs, gsindex, shadowgs); + printk(KERN_INFO "CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds, + es, cr0); + printk(KERN_INFO "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); + printk(KERN_INFO "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); + printk(KERN_INFO "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)); + printk(KERN_INFO "CPU %d:", smp_processor_id()); + __show_regs(regs, 1); + show_trace(NULL, regs, (void *)(regs + 1), regs->bp); } /* @@ -390,7 +223,7 @@ void exit_thread(void) struct task_struct *me = current; struct thread_struct *t = &me->thread; - if (me->thread.io_bitmap_ptr) { + if (me->thread.io_bitmap_ptr) { struct tss_struct *tss = &per_cpu(init_tss, get_cpu()); kfree(t->io_bitmap_ptr); @@ -403,6 +236,14 @@ void exit_thread(void) t->io_bitmap_max = 0; put_cpu(); } +#ifdef CONFIG_X86_DS + /* Free any DS contexts that have not been properly released. */ + if (unlikely(t->ds_ctx)) { + /* we clear debugctl to make sure DS is not used. */ + update_debugctlmsr(0); + ds_free(t->ds_ctx); + } +#endif /* CONFIG_X86_DS */ } void flush_thread(void) @@ -426,10 +267,11 @@ void flush_thread(void) tsk->thread.debugreg3 = 0; tsk->thread.debugreg6 = 0; tsk->thread.debugreg7 = 0; - memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); + memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); /* * Forget coprocessor state.. */ + tsk->fpu_counter = 0; clear_fpu(tsk); clear_used_math(); } @@ -449,17 +291,16 @@ void release_thread(struct task_struct *dead_task) static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr) { - struct user_desc ud = { + struct user_desc ud = { .base_addr = addr, .limit = 0xfffff, .seg_32bit = 1, .limit_in_pages = 1, .useable = 1, }; - struct n_desc_struct *desc = (void *)t->thread.tls_array; + struct desc_struct *desc = t->thread.tls_array; desc += tls; - desc->a = LDT_entry_a(&ud); - desc->b = LDT_entry_b(&ud); + fill_ldt(desc, &ud); } static inline u32 read_32bit_tls(struct task_struct *t, int tls) @@ -478,10 +319,10 @@ void prepare_to_copy(struct task_struct *tsk) int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, unsigned long unused, - struct task_struct * p, struct pt_regs * regs) + struct task_struct *p, struct pt_regs *regs) { int err; - struct pt_regs * childregs; + struct pt_regs *childregs; struct task_struct *me = current; childregs = ((struct pt_regs *) @@ -493,19 +334,19 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, if (sp == ~0UL) childregs->sp = (unsigned long)childregs; - p->thread.rsp = (unsigned long) childregs; - p->thread.rsp0 = (unsigned long) (childregs+1); - p->thread.userrsp = me->thread.userrsp; + p->thread.sp = (unsigned long) childregs; + p->thread.sp0 = (unsigned long) (childregs+1); + p->thread.usersp = me->thread.usersp; set_tsk_thread_flag(p, TIF_FORK); p->thread.fs = me->thread.fs; p->thread.gs = me->thread.gs; - asm("mov %%gs,%0" : "=m" (p->thread.gsindex)); - asm("mov %%fs,%0" : "=m" (p->thread.fsindex)); - asm("mov %%es,%0" : "=m" (p->thread.es)); - asm("mov %%ds,%0" : "=m" (p->thread.ds)); + savesegment(gs, p->thread.gsindex); + savesegment(fs, p->thread.fsindex); + savesegment(es, p->thread.es); + savesegment(ds, p->thread.ds); if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) { p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL); @@ -516,7 +357,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr, IO_BITMAP_BYTES); set_tsk_thread_flag(p, TIF_IO_BITMAP); - } + } /* * Set a new TLS for the child thread? @@ -526,10 +367,10 @@ 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; @@ -541,22 +382,125 @@ out: return err; } +void +start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) +{ + loadsegment(fs, 0); + loadsegment(es, 0); + loadsegment(ds, 0); + load_gs_index(0); + 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); +} +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) +{ + 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(); +} + +int get_tsc_mode(unsigned long adr) +{ + 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); +} + +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) +#define loaddebug(thread, r) set_debugreg(thread->debugreg ## r, r) static inline void __switch_to_xtra(struct task_struct *prev_p, - struct task_struct *next_p, - struct tss_struct *tss) + struct task_struct *next_p, + struct tss_struct *tss) { struct thread_struct *prev, *next; + unsigned long debugctl; prev = &prev_p->thread, next = &next_p->thread; - if (next->debugctlmsr != prev->debugctlmsr) - wrmsrl(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr); + debugctl = prev->debugctlmsr; + +#ifdef CONFIG_X86_DS + { + unsigned long ds_prev = 0, ds_next = 0; + + if (prev->ds_ctx) + ds_prev = (unsigned long)prev->ds_ctx->ds; + if (next->ds_ctx) + ds_next = (unsigned long)next->ds_ctx->ds; + + if (ds_next != ds_prev) { + /* + * 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, ds_next); + } + } +#endif /* CONFIG_X86_DS */ + + if (next->debugctlmsr != debugctl) + update_debugctlmsr(next->debugctlmsr); if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { loaddebug(next, 0); @@ -568,6 +512,15 @@ static inline void __switch_to_xtra(struct task_struct *prev_p, 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. @@ -581,97 +534,120 @@ static inline void __switch_to_xtra(struct task_struct *prev_p, */ 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: + * 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. + * Function graph tracer not supported too. */ -struct task_struct * +__notrace_funcgraph 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 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->i387.fxsave); + if (next_p->fpu_counter > 5) + prefetch(next->xstate); /* * Reload esp0, LDT and the page table pointer: */ - tss->rsp0 = next->rsp0; + load_sp0(tss, next); - /* + /* * Switch DS and ES. * This won't pick up thread selector changes, but I guess that is ok. */ - asm volatile("mov %%es,%0" : "=m" (prev->es)); + savesegment(es, prev->es); if (unlikely(next->es | prev->es)) - loadsegment(es, next->es); - - asm volatile ("mov %%ds,%0" : "=m" (prev->ds)); + 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. */ - { - 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; + 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; } - { - 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; + /* 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->userrsp = read_pda(oldrsp); - write_pda(oldrsp, next->userrsp); - write_pda(pcurrent, next_p); + 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); + (unsigned long)task_stack_page(next_p) + + THREAD_SIZE - PDA_STACKOFFSET); #ifdef CONFIG_CC_STACKPROTECTOR write_pda(stack_canary, next_p->stack_canary); /* @@ -684,15 +660,18 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) /* * Now maybe reload the debug registers and handle I/O bitmaps */ - if (unlikely((task_thread_info(next_p)->flags & _TIF_WORK_CTXSW)) - || test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) + if (unlikely(task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT || + task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV)) __switch_to_xtra(prev_p, next_p, tss); /* If the task has used fpu the last 5 timeslices, just do a full * 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 (next_p->fpu_counter>5) + if (tsk_used_math(next_p) && next_p->fpu_counter > 5) math_state_restore(); return prev_p; } @@ -700,18 +679,18 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) /* * sys_execve() executes a new program. */ -asmlinkage +asmlinkage long sys_execve(char __user *name, char __user * __user *argv, - char __user * __user *envp, struct pt_regs regs) + char __user * __user *envp, struct pt_regs *regs) { long error; - char * filename; + char *filename; filename = getname(name); error = PTR_ERR(filename); - if (IS_ERR(filename)) + if (IS_ERR(filename)) return error; - error = do_execve(filename, argv, envp, ®s); + error = do_execve(filename, argv, envp, regs); putname(filename); return error; } @@ -721,12 +700,12 @@ void set_personality_64bit(void) /* inherit personality from parent */ /* Make sure to be in 64bit mode */ - clear_thread_flag(TIF_IA32); + clear_thread_flag(TIF_IA32); /* TBD: overwrites user setup. Should have two bits. But 64bit processes have always behaved this way, so it's not too bad. The main problem is just that - 32bit childs are affected again. */ + 32bit childs are affected again. */ current->personality &= ~READ_IMPLIES_EXEC; } @@ -763,55 +742,55 @@ asmlinkage long sys_vfork(struct pt_regs *regs) 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.rsp < stack || p->thread.rsp > stack+THREAD_SIZE) + if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE) return 0; - fp = *(u64 *)(p->thread.rsp); - do { + fp = *(u64 *)(p->thread.sp); + 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); - } + } } put_cpu(); break; @@ -819,88 +798,69 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) /* Not strictly needed for fs, but do it for symmetry with gs */ if (addr >= TASK_SIZE_OF(task)) - return -EPERM; + return -EPERM; cpu = get_cpu(); - /* handle small bases via the GDT because that's faster to + /* handle small bases via the GDT because that's faster to switch. */ - if (addr <= 0xffffffff) { + if (addr <= 0xffffffff) { set_32bit_tls(task, FS_TLS, addr); - if (doit) { - load_TLS(&task->thread, cpu); - asm volatile("movl %0,%%fs" :: "r"(FS_TLS_SEL)); + if (doit) { + load_TLS(&task->thread, cpu); + loadsegment(fs, FS_TLS_SEL); } task->thread.fsindex = FS_TLS_SEL; task->thread.fs = 0; - } else { + } else { task->thread.fsindex = 0; task->thread.fs = addr; if (doit) { /* set the selector to 0 to not confuse __switch_to */ - asm volatile("movl %0,%%fs" :: "r" (0)); + loadsegment(fs, 0); ret = checking_wrmsrl(MSR_FS_BASE, addr); } } put_cpu(); break; - case ARCH_GET_FS: { - unsigned long base; + case ARCH_GET_FS: { + unsigned long base; if (task->thread.fsindex == FS_TLS_SEL) base = read_32bit_tls(task, FS_TLS); else if (doit) rdmsrl(MSR_FS_BASE, base); else base = task->thread.fs; - ret = put_user(base, (unsigned long __user *)addr); - break; + ret = put_user(base, (unsigned long __user *)addr); + break; } - case ARCH_GET_GS: { + case ARCH_GET_GS: { unsigned long base; unsigned gsindex; if (task->thread.gsindex == GS_TLS_SEL) base = read_32bit_tls(task, GS_TLS); else if (doit) { - asm("movl %%gs,%0" : "=r" (gsindex)); + savesegment(gs, gsindex); if (gsindex) 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); + ret = put_user(base, (unsigned long __user *)addr); break; } default: ret = -EINVAL; break; - } + } - return ret; -} + return ret; +} long sys_arch_prctl(int code, unsigned long addr) { return do_arch_prctl(current, code, addr); -} - -/* - * Capture the user space registers if the task is not running (in user space) - */ -int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) -{ - struct pt_regs *pp, ptregs; - - pp = task_pt_regs(tsk); - - ptregs = *pp; - ptregs.cs &= 0xffff; - ptregs.ss &= 0xffff; - - elf_core_copy_regs(regs, &ptregs); - - return 1; } unsigned long arch_align_stack(unsigned long sp) @@ -915,4 +875,3 @@ 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; } -