X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fnmi.c;h=8bd1bf9622a7cf1062f33e039c37a2167e5f2918;hb=684f2888847b896faafed87ce4733501d2cc283c;hp=326a8f4f50f8abb802f45b0c44ace03ff45fa151;hpb=f781b03c4b1c713ac000877c8bbc31fc4164a29b;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 326a8f4..8bd1bf9 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -27,6 +27,10 @@ #include #include +#include +#include +#include +#include #include #include @@ -48,7 +52,7 @@ static cpumask_t backtrace_mask = CPU_MASK_NONE; atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ EXPORT_SYMBOL(nmi_active); -unsigned int nmi_watchdog = NMI_DEFAULT; +unsigned int nmi_watchdog = NMI_NONE; EXPORT_SYMBOL(nmi_watchdog); static int panic_on_timeout; @@ -68,7 +72,7 @@ static inline unsigned int get_nmi_count(int cpu) static inline int mce_in_progress(void) { -#if defined(CONFIX_X86_64) && defined(CONFIG_X86_MCE) +#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) return atomic_read(&mce_entry) > 0; #endif return 0; @@ -88,14 +92,6 @@ static inline unsigned int get_timer_irqs(int cpu) #endif } -/* Run after command line and cpu_init init, but before all other checks */ -void nmi_watchdog_default(void) -{ - if (nmi_watchdog != NMI_DEFAULT) - return; - nmi_watchdog = NMI_NONE; -} - #ifdef CONFIG_SMP /* * The performance counters used by NMI_LOCAL_APIC don't trigger when @@ -118,18 +114,37 @@ static __init void nmi_cpu_busy(void *data) } #endif +static void report_broken_nmi(int cpu, int *prev_nmi_count) +{ + printk(KERN_CONT "\n"); + + printk(KERN_WARNING + "WARNING: CPU#%d: NMI appears to be stuck (%d->%d)!\n", + cpu, prev_nmi_count[cpu], get_nmi_count(cpu)); + + printk(KERN_WARNING + "Please report this to bugzilla.kernel.org,\n"); + printk(KERN_WARNING + "and attach the output of the 'dmesg' command.\n"); + + per_cpu(wd_enabled, cpu) = 0; + atomic_dec(&nmi_active); +} + +static void __acpi_nmi_disable(void *__unused) +{ + apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); +} + 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)) + if (!nmi_watchdog_active() || !atomic_read(&nmi_active)) return 0; - prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL); + prev_nmi_count = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); if (!prev_nmi_count) goto error; @@ -137,7 +152,7 @@ int __init check_nmi_watchdog(void) #ifdef CONFIG_SMP if (nmi_watchdog == NMI_LOCAL_APIC) - smp_call_function(nmi_cpu_busy, (void *)&endflag, 0, 0); + smp_call_function(nmi_cpu_busy, (void *)&endflag, 0); #endif for_each_possible_cpu(cpu) @@ -148,15 +163,8 @@ int __init check_nmi_watchdog(void) for_each_online_cpu(cpu) { if (!per_cpu(wd_enabled, cpu)) continue; - if (get_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], - get_nmi_count(cpu)); - per_cpu(wd_enabled, cpu) = 0; - atomic_dec(&nmi_active); - } + if (get_nmi_count(cpu) - prev_nmi_count[cpu] <= 5) + report_broken_nmi(cpu, prev_nmi_count); } endflag = 1; if (!atomic_read(&nmi_active)) { @@ -175,17 +183,22 @@ int __init check_nmi_watchdog(void) kfree(prev_nmi_count); return 0; - error: + if (nmi_watchdog == NMI_IO_APIC) { + if (!timer_through_8259) + disable_8259A_irq(0); + on_each_cpu(__acpi_nmi_disable, NULL, 1); + } + #ifdef CONFIG_X86_32 - timer_ack = !cpu_has_tsc; + timer_ack = 0; #endif return -1; } static int __init setup_nmi_watchdog(char *str) { - int nmi; + unsigned int nmi; if (!strncmp(str, "panic", 5)) { panic_on_timeout = 1; @@ -195,12 +208,17 @@ static int __init setup_nmi_watchdog(char *str) ++str; } - get_option(&str, &nmi); - - if (nmi >= NMI_INVALID || nmi < NMI_NONE) - return 0; + if (!strncmp(str, "lapic", 5)) + nmi_watchdog = NMI_LOCAL_APIC; + else if (!strncmp(str, "ioapic", 6)) + nmi_watchdog = NMI_IO_APIC; + else { + get_option(&str, &nmi); + if (nmi >= NMI_INVALID) + return 0; + nmi_watchdog = nmi; + } - nmi_watchdog = nmi; return 1; } __setup("nmi_watchdog=", setup_nmi_watchdog); @@ -269,7 +287,7 @@ late_initcall(init_lapic_nmi_sysfs); static void __acpi_nmi_enable(void *__unused) { - apic_write_around(APIC_LVT0, APIC_DM_NMI); + apic_write(APIC_LVT0, APIC_DM_NMI); } /* @@ -278,12 +296,7 @@ static void __acpi_nmi_enable(void *__unused) 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_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); + on_each_cpu(__acpi_nmi_enable, NULL, 1); } /* @@ -292,7 +305,16 @@ static void __acpi_nmi_disable(void *__unused) void acpi_nmi_disable(void) { if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) - on_each_cpu(__acpi_nmi_disable, NULL, 0, 1); + on_each_cpu(__acpi_nmi_disable, NULL, 1); +} + +/* + * This function is called as soon the LAPIC NMI watchdog driver has everything + * in place and it's ready to check if the NMIs belong to the NMI watchdog + */ +void cpu_nmi_set_wd_enabled(void) +{ + __get_cpu_var(wd_enabled) = 1; } void setup_apic_nmi_watchdog(void *unused) @@ -307,8 +329,6 @@ void setup_apic_nmi_watchdog(void *unused) 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; return; @@ -323,13 +343,14 @@ 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) + if (!nmi_watchdog_active()) return; if (__get_cpu_var(wd_enabled) == 0) return; if (nmi_watchdog == NMI_LOCAL_APIC) lapic_watchdog_stop(); + else + __acpi_nmi_disable(NULL); __get_cpu_var(wd_enabled) = 0; atomic_dec(&nmi_active); } @@ -354,8 +375,7 @@ static DEFINE_PER_CPU(int, nmi_touch); void touch_nmi_watchdog(void) { - if (nmi_watchdog == NMI_LOCAL_APIC || - nmi_watchdog == NMI_IO_APIC) { + if (nmi_watchdog_active()) { unsigned cpu; /* @@ -456,6 +476,31 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) #ifdef CONFIG_SYSCTL +static void enable_ioapic_nmi_watchdog_single(void *unused) +{ + __get_cpu_var(wd_enabled) = 1; + atomic_inc(&nmi_active); + __acpi_nmi_enable(NULL); +} + +static void enable_ioapic_nmi_watchdog(void) +{ + on_each_cpu(enable_ioapic_nmi_watchdog_single, NULL, 1); + touch_nmi_watchdog(); +} + +static void disable_ioapic_nmi_watchdog(void) +{ + on_each_cpu(stop_apic_nmi_watchdog, NULL, 1); +} + +static int __init setup_unknown_nmi_panic(char *str) +{ + unknown_nmi_panic = 1; + return 1; +} +__setup("unknown_nmi_panic", setup_unknown_nmi_panic); + static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) { unsigned char reason = get_nmi_reason(); @@ -480,29 +525,22 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, if (!!old_state == !!nmi_watchdog_enabled) return 0; - if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { + if (atomic_read(&nmi_active) < 0 || !nmi_watchdog_active()) { 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 if (nmi_watchdog == NMI_IO_APIC) { + if (nmi_watchdog_enabled) + enable_ioapic_nmi_watchdog(); + else + disable_ioapic_nmi_watchdog(); } else { printk(KERN_WARNING "NMI watchdog doesn't know what hardware to touch\n");