diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/perfctr-watchdog.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/nmi.c (renamed from arch/x86/kernel/nmi_64.c) | 218 | ||||
| -rw-r--r-- | arch/x86/kernel/nmi_32.c | 467 | ||||
| -rw-r--r-- | arch/x86/kernel/traps_32.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/traps_64.c | 28 |
6 files changed, 172 insertions, 555 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 77807d4769c..c82b4e1738a 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -53,7 +53,7 @@ obj-$(CONFIG_X86_32_SMP) += smpcommon.o obj-$(CONFIG_X86_64_SMP) += tsc_sync.o smpcommon.o obj-$(CONFIG_X86_TRAMPOLINE) += trampoline_$(BITS).o obj-$(CONFIG_X86_MPPARSE) += mpparse.o -obj-$(CONFIG_X86_LOCAL_APIC) += apic_$(BITS).o nmi_$(BITS).o +obj-$(CONFIG_X86_LOCAL_APIC) += apic_$(BITS).o nmi.o obj-$(CONFIG_X86_IO_APIC) += io_apic_$(BITS).o obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c index f9ae93adffe..ddda4b64f54 100644 --- a/arch/x86/kernel/cpu/perfctr-watchdog.c +++ b/arch/x86/kernel/cpu/perfctr-watchdog.c @@ -181,7 +181,9 @@ void disable_lapic_nmi_watchdog(void) return; on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1); - wd_ops->unreserve(); + + if (wd_ops) + wd_ops->unreserve(); BUG_ON(atomic_read(&nmi_active) != 0); } diff --git a/arch/x86/kernel/nmi_64.c b/arch/x86/kernel/nmi.c index 5a29ded994f..fd680c73ba7 100644 --- a/arch/x86/kernel/nmi_64.c +++ b/arch/x86/kernel/nmi.c @@ -6,10 +6,13 @@ * Fixes: * Mikael Pettersson : AMD K7 support for local APIC NMI watchdog. * Mikael Pettersson : Power Management for local APIC NMI watchdog. + * Mikael Pettersson : Pentium 4 support for local APIC NMI watchdog. * Pavel Machek and * Mikael Pettersson : PM converted to driver model. Disable/enable API. */ +#include <asm/apic.h> + #include <linux/nmi.h> #include <linux/mm.h> #include <linux/delay.h> @@ -17,20 +20,22 @@ #include <linux/module.h> #include <linux/sysdev.h> #include <linux/sysctl.h> +#include <linux/percpu.h> #include <linux/kprobes.h> #include <linux/cpumask.h> +#include <linux/kernel_stat.h> #include <linux/kdebug.h> +#include <linux/smp.h> -#include <asm/smp.h> -#include <asm/nmi.h> #include <asm/proto.h> +#include <asm/timer.h> + #include <asm/mce.h> #include <mach_traps.h> int unknown_nmi_panic; int nmi_watchdog_enabled; -int panic_on_unrecovered_nmi; static cpumask_t backtrace_mask = CPU_MASK_NONE; @@ -41,12 +46,47 @@ static cpumask_t backtrace_mask = CPU_MASK_NONE; * 0: the lapic NMI watchdog is disabled, but can be enabled */ atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ -static int panic_on_timeout; +EXPORT_SYMBOL(nmi_active); unsigned int nmi_watchdog = NMI_DEFAULT; -static unsigned int nmi_hz = HZ; +EXPORT_SYMBOL(nmi_watchdog); + +static int panic_on_timeout; +static unsigned int nmi_hz = HZ; static DEFINE_PER_CPU(short, wd_enabled); +static int endflag __initdata; + +static inline unsigned int get_nmi_count(int cpu) +{ +#ifdef CONFIG_X86_64 + return cpu_pda(cpu)->__nmi_count; +#else + return nmi_count(cpu); +#endif +} + +static inline int mce_in_progress(void) +{ +#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) + return atomic_read(&mce_entry) > 0; +#endif + return 0; +} + +/* + * Take the local apic timer and PIT/HPET into account. We don't + * know which one is active, when we have highres/dyntick on + */ +static inline unsigned int get_timer_irqs(int cpu) +{ +#ifdef CONFIG_X86_64 + return read_pda(apic_timer_irqs) + read_pda(irq0_irqs); +#else + return per_cpu(irq_stat, cpu).apic_timer_irqs + + per_cpu(irq_stat, cpu).irq0_irqs; +#endif +} /* Run after command line and cpu_init init, but before all other checks */ void nmi_watchdog_default(void) @@ -56,22 +96,23 @@ void nmi_watchdog_default(void) nmi_watchdog = NMI_NONE; } -static int endflag __initdata = 0; - #ifdef CONFIG_SMP -/* The performance counters used by NMI_LOCAL_APIC don't trigger when +/* + * The performance counters used by NMI_LOCAL_APIC don't trigger when * the CPU is idle. To make sure the NMI watchdog really ticks on all * CPUs during the test make them busy. */ static __init void nmi_cpu_busy(void *data) { local_irq_enable_in_hardirq(); - /* Intentionally don't use cpu_relax here. This is - to make sure that the performance counter really ticks, - even if there is a simulator or similar that catches the - pause instruction. On a real HT machine this is fine because - all other CPUs are busy with "useless" delay loops and don't - care if they get somewhat less cycles. */ + /* + * Intentionally don't use cpu_relax here. This is + * to make sure that the performance counter really ticks, + * even if there is a simulator or similar that catches the + * pause instruction. On a real HT machine this is fine because + * all other CPUs are busy with "useless" delay loops and don't + * care if they get somewhat less cycles. + */ while (endflag == 0) mb(); } @@ -79,10 +120,10 @@ static __init void nmi_cpu_busy(void *data) int __init check_nmi_watchdog(void) { - int *prev_nmi_count; + unsigned int *prev_nmi_count; int cpu; - if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED)) + if (nmi_watchdog == NMI_NONE || nmi_watchdog == NMI_DISABLED) return 0; if (!atomic_read(&nmi_active)) @@ -90,7 +131,7 @@ int __init check_nmi_watchdog(void) prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL); if (!prev_nmi_count) - return -1; + goto error; printk(KERN_INFO "Testing NMI watchdog ... "); @@ -99,20 +140,20 @@ int __init check_nmi_watchdog(void) smp_call_function(nmi_cpu_busy, (void *)&endflag, 0, 0); #endif - for (cpu = 0; cpu < NR_CPUS; cpu++) - prev_nmi_count[cpu] = cpu_pda(cpu)->__nmi_count; + for_each_possible_cpu(cpu) + prev_nmi_count[cpu] = get_nmi_count(cpu); local_irq_enable(); - mdelay((20*1000)/nmi_hz); // wait 20 ticks + mdelay((20 * 1000) / nmi_hz); /* wait 20 ticks */ for_each_online_cpu(cpu) { if (!per_cpu(wd_enabled, cpu)) continue; - if (cpu_pda(cpu)->__nmi_count - prev_nmi_count[cpu] <= 5) { + if (get_nmi_count(cpu) - prev_nmi_count[cpu] <= 5) { printk(KERN_WARNING "WARNING: CPU#%d: NMI " - "appears to be stuck (%d->%d)!\n", + "appears to be stuck (%d->%d)!\n", cpu, prev_nmi_count[cpu], - cpu_pda(cpu)->__nmi_count); + get_nmi_count(cpu)); per_cpu(wd_enabled, cpu) = 0; atomic_dec(&nmi_active); } @@ -121,24 +162,32 @@ int __init check_nmi_watchdog(void) if (!atomic_read(&nmi_active)) { kfree(prev_nmi_count); atomic_set(&nmi_active, -1); - return -1; + goto error; } printk("OK.\n"); - /* now that we know it works we can reduce NMI frequency to - something more reasonable; makes a difference in some configs */ + /* + * now that we know it works we can reduce NMI frequency to + * something more reasonable; makes a difference in some configs + */ if (nmi_watchdog == NMI_LOCAL_APIC) nmi_hz = lapic_adjust_nmi_hz(1); kfree(prev_nmi_count); return 0; + +error: +#ifdef CONFIG_X86_32 + timer_ack = !cpu_has_tsc; +#endif + return -1; } static int __init setup_nmi_watchdog(char *str) { int nmi; - if (!strncmp(str,"panic",5)) { + if (!strncmp(str, "panic", 5)) { panic_on_timeout = 1; str = strchr(str, ','); if (!str) @@ -148,15 +197,17 @@ static int __init setup_nmi_watchdog(char *str) get_option(&str, &nmi); - if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE)) + if (nmi >= NMI_INVALID || nmi < NMI_NONE) return 0; nmi_watchdog = nmi; return 1; } - __setup("nmi_watchdog=", setup_nmi_watchdog); +/* + * Suspend/resume support + */ #ifdef CONFIG_PM static int nmi_pm_active; /* nmi_active before suspend */ @@ -195,7 +246,8 @@ static int __init init_lapic_nmi_sysfs(void) { int error; - /* should really be a BUG_ON but b/c this is an + /* + * should really be a BUG_ON but b/c this is an * init call, it just doesn't work. -dcz */ if (nmi_watchdog != NMI_LOCAL_APIC) @@ -209,6 +261,7 @@ static int __init init_lapic_nmi_sysfs(void) error = sysdev_register(&device_lapic_nmi); return error; } + /* must come after the local APIC's device_initcall() */ late_initcall(init_lapic_nmi_sysfs); @@ -216,7 +269,7 @@ late_initcall(init_lapic_nmi_sysfs); static void __acpi_nmi_enable(void *__unused) { - apic_write(APIC_LVT0, APIC_DM_NMI); + apic_write_around(APIC_LVT0, APIC_DM_NMI); } /* @@ -230,7 +283,7 @@ void acpi_nmi_enable(void) static void __acpi_nmi_disable(void *__unused) { - apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); + apic_write_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); } /* @@ -249,11 +302,12 @@ void setup_apic_nmi_watchdog(void *unused) /* cheap hack to support suspend/resume */ /* if cpu0 is not active neither should the other cpus */ - if ((smp_processor_id() != 0) && (atomic_read(&nmi_active) <= 0)) + if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0) return; switch (nmi_watchdog) { case NMI_LOCAL_APIC: + /* enable it before to avoid race with handler */ __get_cpu_var(wd_enabled) = 1; if (lapic_watchdog_init(nmi_hz) < 0) { __get_cpu_var(wd_enabled) = 0; @@ -269,9 +323,9 @@ void setup_apic_nmi_watchdog(void *unused) void stop_apic_nmi_watchdog(void *unused) { /* only support LOCAL and IO APICs for now */ - if ((nmi_watchdog != NMI_LOCAL_APIC) && - (nmi_watchdog != NMI_IO_APIC)) - return; + if (nmi_watchdog != NMI_LOCAL_APIC && + nmi_watchdog != NMI_IO_APIC) + return; if (__get_cpu_var(wd_enabled) == 0) return; if (nmi_watchdog == NMI_LOCAL_APIC) @@ -287,6 +341,11 @@ void stop_apic_nmi_watchdog(void *unused) * * as these watchdog NMI IRQs are generated on every CPU, we only * have to check the current processor. + * + * since NMIs don't listen to _any_ locks, we have to be extremely + * careful not to rely on unsafe variables. The printk might lock + * up though, so we have to break up any console locks first ... + * [when there will be more tty-related locks, break them up here too!] */ static DEFINE_PER_CPU(unsigned, last_irq_sum); @@ -295,11 +354,12 @@ static DEFINE_PER_CPU(int, nmi_touch); void touch_nmi_watchdog(void) { - if (nmi_watchdog > 0) { + if (nmi_watchdog == NMI_LOCAL_APIC || + nmi_watchdog == NMI_IO_APIC) { unsigned cpu; /* - * Tell other CPUs to reset their alert counters. We cannot + * Tell other CPUs to reset their alert counters. We cannot * do it ourselves because the alert count increase is not * atomic. */ @@ -309,6 +369,9 @@ void touch_nmi_watchdog(void) } } + /* + * Tickle the softlockup detector too: + */ touch_softlockup_watchdog(); } EXPORT_SYMBOL(touch_nmi_watchdog); @@ -316,7 +379,12 @@ EXPORT_SYMBOL(touch_nmi_watchdog); notrace __kprobes int nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) { - int sum; + /* + * Since current_thread_info()-> is always on the stack, and we + * always switch the stack NMI-atomically, it's safe to use + * smp_processor_id(). + */ + unsigned int sum; int touched = 0; int cpu = smp_processor_id(); int rc = 0; @@ -328,7 +396,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) touched = 1; } - sum = read_pda(apic_timer_irqs) + read_pda(irq0_irqs); + sum = get_timer_irqs(cpu); + if (__get_cpu_var(nmi_touch)) { __get_cpu_var(nmi_touch) = 0; touched = 1; @@ -338,28 +407,29 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) static DEFINE_SPINLOCK(lock); /* Serialise the printks */ spin_lock(&lock); - printk("NMI backtrace for cpu %d\n", cpu); + printk(KERN_WARNING "NMI backtrace for cpu %d\n", cpu); dump_stack(); spin_unlock(&lock); cpu_clear(cpu, backtrace_mask); } -#ifdef CONFIG_X86_MCE - /* Could check oops_in_progress here too, but it's safer - not too */ - if (atomic_read(&mce_entry) > 0) + /* Could check oops_in_progress here too, but it's safer not to */ + if (mce_in_progress()) touched = 1; -#endif - /* if the apic timer isn't firing, this cpu isn't doing much */ + + /* if the none of the timers isn't firing, this cpu isn't doing much */ if (!touched && __get_cpu_var(last_irq_sum) == sum) { /* * Ayiee, looks like this CPU is stuck ... * wait a few IRQs (5 seconds) before doing the oops ... */ local_inc(&__get_cpu_var(alert_counter)); - if (local_read(&__get_cpu_var(alert_counter)) == 5*nmi_hz) - die_nmi("NMI Watchdog detected LOCKUP on CPU %d\n", regs, - panic_on_timeout); + if (local_read(&__get_cpu_var(alert_counter)) == 5 * nmi_hz) + /* + * die_nmi will return ONLY if NOTIFY_STOP happens.. + */ + die_nmi("BUG: NMI Watchdog detected LOCKUP", + regs, panic_on_timeout); } else { __get_cpu_var(last_irq_sum) = sum; local_set(&__get_cpu_var(alert_counter), 0); @@ -373,7 +443,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) rc |= lapic_wd_event(nmi_hz); break; case NMI_IO_APIC: - /* don't know how to accurately check for this. + /* + * don't know how to accurately check for this. * just assume it was a watchdog timer interrupt * This matches the old behaviour. */ @@ -383,30 +454,6 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) return rc; } -static unsigned ignore_nmis; - -asmlinkage notrace __kprobes void -do_nmi(struct pt_regs *regs, long error_code) -{ - nmi_enter(); - add_pda(__nmi_count,1); - if (!ignore_nmis) - default_do_nmi(regs); - nmi_exit(); -} - -void stop_nmi(void) -{ - acpi_nmi_disable(); - ignore_nmis++; -} - -void restart_nmi(void) -{ - ignore_nmis--; - acpi_nmi_enable(); -} - #ifdef CONFIG_SYSCTL static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) @@ -415,7 +462,7 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) char buf[64]; sprintf(buf, "NMI received for unknown reason %02x\n", reason); - die_nmi(buf, regs, 1); /* Always panic here */ + die_nmi(buf, regs, 1); /* Always panic here */ return 0; } @@ -434,27 +481,37 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, return 0; if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { - printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); + printk(KERN_WARNING + "NMI watchdog is permanently disabled\n"); return -EIO; } /* if nmi_watchdog is not set yet, then set it */ nmi_watchdog_default(); +#ifdef CONFIG_X86_32 + if (nmi_watchdog == NMI_NONE) { + if (lapic_watchdog_ok()) + nmi_watchdog = NMI_LOCAL_APIC; + else + nmi_watchdog = NMI_IO_APIC; + } +#endif + if (nmi_watchdog == NMI_LOCAL_APIC) { if (nmi_watchdog_enabled) enable_lapic_nmi_watchdog(); else disable_lapic_nmi_watchdog(); } else { - printk( KERN_WARNING + printk(KERN_WARNING "NMI watchdog doesn't know what hardware to touch\n"); return -EIO; } return 0; } -#endif +#endif /* CONFIG_SYSCTL */ int do_nmi_callback(struct pt_regs *regs, int cpu) { @@ -477,6 +534,3 @@ void __trigger_all_cpu_backtrace(void) mdelay(1); } } - -EXPORT_SYMBOL(nmi_active); -EXPORT_SYMBOL(nmi_watchdog); diff --git a/arch/x86/kernel/nmi_32.c b/arch/x86/kernel/nmi_32.c deleted file mode 100644 index 84160f74eeb..00000000000 --- a/arch/x86/kernel/nmi_32.c +++ /dev/null @@ -1,467 +0,0 @@ -/* - * NMI watchdog support on APIC systems - * - * Started by Ingo Molnar <mingo@redhat.com> - * - * Fixes: - * Mikael Pettersson : AMD K7 support for local APIC NMI watchdog. - * Mikael Pettersson : Power Management for local APIC NMI watchdog. - * Mikael Pettersson : Pentium 4 support for local APIC NMI watchdog. - * Pavel Machek and - * Mikael Pettersson : PM converted to driver model. Disable/enable API. - */ - -#include <linux/delay.h> -#include <linux/interrupt.h> -#include <linux/module.h> -#include <linux/nmi.h> -#include <linux/sysdev.h> -#include <linux/sysctl.h> -#include <linux/percpu.h> -#include <linux/kprobes.h> -#include <linux/cpumask.h> -#include <linux/kernel_stat.h> -#include <linux/kdebug.h> -#include <linux/slab.h> - -#include <asm/smp.h> -#include <asm/nmi.h> - -#include "mach_traps.h" - -int unknown_nmi_panic; -int nmi_watchdog_enabled; - -static cpumask_t backtrace_mask = CPU_MASK_NONE; - -/* nmi_active: - * >0: the lapic NMI watchdog is active, but can be disabled - * <0: the lapic NMI watchdog has not been set up, and cannot - * be enabled - * 0: the lapic NMI watchdog is disabled, but can be enabled - */ -atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ - -unsigned int nmi_watchdog = NMI_DEFAULT; -static unsigned int nmi_hz = HZ; - -static DEFINE_PER_CPU(short, wd_enabled); - -static int endflag __initdata = 0; - -#ifdef CONFIG_SMP -/* The performance counters used by NMI_LOCAL_APIC don't trigger when - * the CPU is idle. To make sure the NMI watchdog really ticks on all - * CPUs during the test make them busy. - */ -static __init void nmi_cpu_busy(void *data) -{ - local_irq_enable_in_hardirq(); - /* Intentionally don't use cpu_relax here. This is - to make sure that the performance counter really ticks, - even if there is a simulator or similar that catches the - pause instruction. On a real HT machine this is fine because - all other CPUs are busy with "useless" delay loops and don't - care if they get somewhat less cycles. */ - while (endflag == 0) - mb(); -} -#endif - -int __init check_nmi_watchdog(void) -{ - unsigned int *prev_nmi_count; - int cpu; - - if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED)) - return 0; - - if (!atomic_read(&nmi_active)) - return 0; - - prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL); - if (!prev_nmi_count) - return -1; - - printk(KERN_INFO "Testing NMI watchdog ... "); - -#ifdef CONFIG_SMP - if (nmi_watchdog == NMI_LOCAL_APIC) - smp_call_function(nmi_cpu_busy, (void *)&endflag, 0, 0); -#endif - - for_each_possible_cpu(cpu) - prev_nmi_count[cpu] = nmi_count(cpu); - local_irq_enable(); - mdelay((20*1000)/nmi_hz); // wait 20 ticks - - for_each_possible_cpu(cpu) { -#ifdef CONFIG_SMP - /* Check cpu_callin_map here because that is set - after the timer is started. */ - if (!cpu_isset(cpu, cpu_callin_map)) - continue; -#endif - if (!per_cpu(wd_enabled, cpu)) - continue; - if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) { - printk(KERN_WARNING "WARNING: CPU#%d: NMI " - "appears to be stuck (%d->%d)!\n", - cpu, - prev_nmi_count[cpu], - nmi_count(cpu)); - per_cpu(wd_enabled, cpu) = 0; - atomic_dec(&nmi_active); - } - } - endflag = 1; - if (!atomic_read(&nmi_active)) { - kfree(prev_nmi_count); - atomic_set(&nmi_active, -1); - return -1; - } - printk("OK.\n"); - - /* now that we know it works we can reduce NMI frequency to - something more reasonable; makes a difference in some configs */ - if (nmi_watchdog == NMI_LOCAL_APIC) - nmi_hz = lapic_adjust_nmi_hz(1); - - kfree(prev_nmi_count); - return 0; -} - -static int __init setup_nmi_watchdog(char *str) -{ - int nmi; - - get_option(&str, &nmi); - - if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE)) - return 0; - - nmi_watchdog = nmi; - return 1; -} - -__setup("nmi_watchdog=", setup_nmi_watchdog); - - -/* Suspend/resume support */ - -#ifdef CONFIG_PM - -static int nmi_pm_active; /* nmi_active before suspend */ - -static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state) -{ - /* only CPU0 goes here, other CPUs should be offline */ - nmi_pm_active = atomic_read(&nmi_active); - stop_apic_nmi_watchdog(NULL); - BUG_ON(atomic_read(&nmi_active) != 0); - return 0; -} - -static int lapic_nmi_resume(struct sys_device *dev) -{ - /* only CPU0 goes here, other CPUs should be offline */ - if (nmi_pm_active > 0) { - setup_apic_nmi_watchdog(NULL); - touch_nmi_watchdog(); - } - return 0; -} - - -static struct sysdev_class nmi_sysclass = { - .name = "lapic_nmi", - .resume = lapic_nmi_resume, - .suspend = lapic_nmi_suspend, -}; - -static struct sys_device device_lapic_nmi = { - .id = 0, - .cls = &nmi_sysclass, -}; - -static int __init init_lapic_nmi_sysfs(void) -{ - int error; - - /* should really be a BUG_ON but b/c this is an - * init call, it just doesn't work. -dcz - */ - if (nmi_watchdog != NMI_LOCAL_APIC) - return 0; - - if (atomic_read(&nmi_active) < 0) - return 0; - - error = sysdev_class_register(&nmi_sysclass); - if (!error) - error = sysdev_register(&device_lapic_nmi); - return error; -} -/* must come after the local APIC's device_initcall() */ -late_initcall(init_lapic_nmi_sysfs); - -#endif /* CONFIG_PM */ - -static void __acpi_nmi_enable(void *__unused) -{ - apic_write_around(APIC_LVT0, APIC_DM_NMI); -} - -/* - * Enable timer based NMIs on all CPUs: - */ -void acpi_nmi_enable(void) -{ - if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) - on_each_cpu(__acpi_nmi_enable, NULL, 0, 1); -} - -static void __acpi_nmi_disable(void *__unused) -{ - apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); -} - -/* - * Disable timer based NMIs on all CPUs: - */ -void acpi_nmi_disable(void) -{ - if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) - on_each_cpu(__acpi_nmi_disable, NULL, 0, 1); -} - -void setup_apic_nmi_watchdog(void *unused) -{ - if (__get_cpu_var(wd_enabled)) - return; - - /* cheap hack to support suspend/resume */ - /* if cpu0 is not active neither should the other cpus */ - if ((smp_processor_id() != 0) && (atomic_read(&nmi_active) <= 0)) - return; - - switch (nmi_watchdog) { - case NMI_LOCAL_APIC: - __get_cpu_var(wd_enabled) = 1; /* enable it before to avoid race with handler */ - if (lapic_watchdog_init(nmi_hz) < 0) { - __get_cpu_var(wd_enabled) = 0; - return; - } - /* FALL THROUGH */ - case NMI_IO_APIC: - __get_cpu_var(wd_enabled) = 1; - atomic_inc(&nmi_active); - } -} - -void stop_apic_nmi_watchdog(void *unused) -{ - /* only support LOCAL and IO APICs for now */ - if ((nmi_watchdog != NMI_LOCAL_APIC) && - (nmi_watchdog != NMI_IO_APIC)) - return; - if (__get_cpu_var(wd_enabled) == 0) - return; - if (nmi_watchdog == NMI_LOCAL_APIC) - lapic_watchdog_stop(); - __get_cpu_var(wd_enabled) = 0; - atomic_dec(&nmi_active); -} - -/* - * the best way to detect whether a CPU has a 'hard lockup' problem - * is to check it's local APIC timer IRQ counts. If they are not - * changing then that CPU has some problem. - * - * as these watchdog NMI IRQs are generated on every CPU, we only - * have to check the current processor. - * - * since NMIs don't listen to _any_ locks, we have to be extremely - * careful not to rely on unsafe variables. The printk might lock - * up though, so we have to break up any console locks first ... - * [when there will be more tty-related locks, break them up - * here too!] - */ - -static unsigned int - last_irq_sums [NR_CPUS], - alert_counter [NR_CPUS]; - -void touch_nmi_watchdog(void) -{ - if (nmi_watchdog > 0) { - unsigned cpu; - - /* - * Just reset the alert counters, (other CPUs might be - * spinning on locks we hold): - */ - for_each_present_cpu(cpu) { - if (alert_counter[cpu]) - alert_counter[cpu] = 0; - } - } - - /* - * Tickle the softlockup detector too: - */ - touch_softlockup_watchdog(); -} -EXPORT_SYMBOL(touch_nmi_watchdog); - -extern void die_nmi(struct pt_regs *, const char *msg); - -notrace __kprobes int -nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) -{ - - /* - * Since current_thread_info()-> is always on the stack, and we - * always switch the stack NMI-atomically, it's safe to use - * smp_processor_id(). - */ - unsigned int sum; - int touched = 0; - int cpu = smp_processor_id(); - int rc = 0; - - /* check for other users first */ - if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) - == NOTIFY_STOP) { - rc = 1; - touched = 1; - } - - if (cpu_isset(cpu, backtrace_mask)) { - static DEFINE_SPINLOCK(lock); /* Serialise the printks */ - - spin_lock(&lock); - printk("NMI backtrace for cpu %d\n", cpu); - dump_stack(); - spin_unlock(&lock); - cpu_clear(cpu, backtrace_mask); - } - - /* - * Take the local apic timer and PIT/HPET into account. We don't - * know which one is active, when we have highres/dyntick on - */ - sum = per_cpu(irq_stat, cpu).apic_timer_irqs + - per_cpu(irq_stat, cpu).irq0_irqs; - - /* if the none of the timers isn't firing, this cpu isn't doing much */ - if (!touched && last_irq_sums[cpu] == sum) { - /* - * Ayiee, looks like this CPU is stuck ... - * wait a few IRQs (5 seconds) before doing the oops ... - */ - alert_counter[cpu]++; - if (alert_counter[cpu] == 5*nmi_hz) - /* - * die_nmi will return ONLY if NOTIFY_STOP happens.. - */ - die_nmi(regs, "BUG: NMI Watchdog detected LOCKUP"); - } else { - last_irq_sums[cpu] = sum; - alert_counter[cpu] = 0; - } - /* see if the nmi watchdog went off */ - if (!__get_cpu_var(wd_enabled)) - return rc; - switch (nmi_watchdog) { - case NMI_LOCAL_APIC: - rc |= lapic_wd_event(nmi_hz); - break; - case NMI_IO_APIC: - /* don't know how to accurately check for this. - * just assume it was a watchdog timer interrupt - * This matches the old behaviour. - */ - rc = 1; - break; - } - return rc; -} - -#ifdef CONFIG_SYSCTL - -static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) -{ - unsigned char reason = get_nmi_reason(); - char buf[64]; - - sprintf(buf, "NMI received for unknown reason %02x\n", reason); - die_nmi(regs, buf); - return 0; -} - -/* - * proc handler for /proc/sys/kernel/nmi - */ -int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, - void __user *buffer, size_t *length, loff_t *ppos) -{ - int old_state; - - nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0; - old_state = nmi_watchdog_enabled; - proc_dointvec(table, write, file, buffer, length, ppos); - if (!!old_state == !!nmi_watchdog_enabled) - return 0; - - if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { - printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); - return -EIO; - } - - if (nmi_watchdog == NMI_DEFAULT) { - if (lapic_watchdog_ok()) - nmi_watchdog = NMI_LOCAL_APIC; - else - nmi_watchdog = NMI_IO_APIC; - } - - if (nmi_watchdog == NMI_LOCAL_APIC) { - if (nmi_watchdog_enabled) - enable_lapic_nmi_watchdog(); - else - disable_lapic_nmi_watchdog(); - } else { - printk( KERN_WARNING - "NMI watchdog doesn't know what hardware to touch\n"); - return -EIO; - } - return 0; -} - -#endif - -int do_nmi_callback(struct pt_regs *regs, int cpu) -{ -#ifdef CONFIG_SYSCTL - if (unknown_nmi_panic) - return unknown_nmi_panic_callback(regs, cpu); -#endif - return 0; -} - -void __trigger_all_cpu_backtrace(void) -{ - int i; - - backtrace_mask = cpu_online_map; - /* Wait for up to 10 seconds for all CPUs to do the backtrace */ - for (i = 0; i < 10 * 1000; i++) { - if (cpus_empty(backtrace_mask)) - break; - mdelay(1); - } -} - -EXPORT_SYMBOL(nmi_active); -EXPORT_SYMBOL(nmi_watchdog); diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c index 08d752de4ee..cf37d20b1ba 100644 --- a/arch/x86/kernel/traps_32.c +++ b/arch/x86/kernel/traps_32.c @@ -756,9 +756,9 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs) static DEFINE_SPINLOCK(nmi_print_lock); -void notrace __kprobes die_nmi(struct pt_regs *regs, const char *msg) +void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic) { - if (notify_die(DIE_NMIWATCHDOG, msg, regs, 0, 2, SIGINT) == NOTIFY_STOP) + if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP) return; spin_lock(&nmi_print_lock); @@ -767,10 +767,12 @@ void notrace __kprobes die_nmi(struct pt_regs *regs, const char *msg) * to get a message out: */ bust_spinlocks(1); - printk(KERN_EMERG "%s", msg); + printk(KERN_EMERG "%s", str); printk(" on CPU%d, ip %08lx, registers:\n", smp_processor_id(), regs->ip); show_registers(regs); + if (do_panic) + panic("Non maskable interrupt"); console_silent(); spin_unlock(&nmi_print_lock); bust_spinlocks(0); diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c index adff76ea97c..e4a380797dc 100644 --- a/arch/x86/kernel/traps_64.c +++ b/arch/x86/kernel/traps_64.c @@ -76,7 +76,9 @@ asmlinkage void alignment_check(void); asmlinkage void machine_check(void); asmlinkage void spurious_interrupt_bug(void); +int panic_on_unrecovered_nmi; static unsigned int code_bytes = 64; +static unsigned ignore_nmis; static inline void conditional_sti(struct pt_regs *regs) { @@ -614,7 +616,9 @@ die_nmi(char *str, struct pt_regs *regs, int do_panic) * We are in trouble anyway, lets at least try * to get a message out. */ - printk(str, smp_processor_id()); + printk(KERN_EMERG "%s", str); + printk(" on CPU%d, ip %08lx, registers:\n", + smp_processor_id(), regs->ip); show_registers(regs); if (kexec_should_crash(current)) crash_kexec(regs); @@ -865,6 +869,28 @@ asmlinkage notrace __kprobes void default_do_nmi(struct pt_regs *regs) io_check_error(reason, regs); } +asmlinkage notrace __kprobes void +do_nmi(struct pt_regs *regs, long error_code) +{ + nmi_enter(); + add_pda(__nmi_count, 1); + if (!ignore_nmis) + default_do_nmi(regs); + nmi_exit(); +} + +void stop_nmi(void) +{ + acpi_nmi_disable(); + ignore_nmis++; +} + +void restart_nmi(void) +{ + ignore_nmis--; + acpi_nmi_enable(); +} + /* runs on IST stack. */ asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code) { |