diff options
| -rw-r--r-- | arch/x86/include/asm/nmi.h | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/apic/Makefile | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/apic/hw_nmi.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/apic/nmi.c | 567 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 9 | ||||
| -rw-r--r-- | include/linux/nmi.h | 6 | ||||
| -rw-r--r-- | kernel/sysctl.c | 16 |
7 files changed, 5 insertions, 608 deletions
diff --git a/arch/x86/include/asm/nmi.h b/arch/x86/include/asm/nmi.h index 932f0f86b4b..33292ec848c 100644 --- a/arch/x86/include/asm/nmi.h +++ b/arch/x86/include/asm/nmi.h | |||
| @@ -17,9 +17,6 @@ int do_nmi_callback(struct pt_regs *regs, int cpu); | |||
| 17 | 17 | ||
| 18 | extern void die_nmi(char *str, struct pt_regs *regs, int do_panic); | 18 | extern void die_nmi(char *str, struct pt_regs *regs, int do_panic); |
| 19 | extern int check_nmi_watchdog(void); | 19 | extern int check_nmi_watchdog(void); |
| 20 | #if !defined(CONFIG_LOCKUP_DETECTOR) | ||
| 21 | extern int nmi_watchdog_enabled; | ||
| 22 | #endif | ||
| 23 | extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); | 20 | extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); |
| 24 | extern int reserve_perfctr_nmi(unsigned int); | 21 | extern int reserve_perfctr_nmi(unsigned int); |
| 25 | extern void release_perfctr_nmi(unsigned int); | 22 | extern void release_perfctr_nmi(unsigned int); |
| @@ -30,7 +27,6 @@ extern void setup_apic_nmi_watchdog(void *); | |||
| 30 | extern void stop_apic_nmi_watchdog(void *); | 27 | extern void stop_apic_nmi_watchdog(void *); |
| 31 | extern void disable_timer_nmi_watchdog(void); | 28 | extern void disable_timer_nmi_watchdog(void); |
| 32 | extern void enable_timer_nmi_watchdog(void); | 29 | extern void enable_timer_nmi_watchdog(void); |
| 33 | extern int nmi_watchdog_tick(struct pt_regs *regs, unsigned reason); | ||
| 34 | extern void cpu_nmi_set_wd_enabled(void); | 30 | extern void cpu_nmi_set_wd_enabled(void); |
| 35 | 31 | ||
| 36 | extern atomic_t nmi_active; | 32 | extern atomic_t nmi_active; |
diff --git a/arch/x86/kernel/apic/Makefile b/arch/x86/kernel/apic/Makefile index 910f20b457c..3966b564ea4 100644 --- a/arch/x86/kernel/apic/Makefile +++ b/arch/x86/kernel/apic/Makefile | |||
| @@ -3,10 +3,7 @@ | |||
| 3 | # | 3 | # |
| 4 | 4 | ||
| 5 | obj-$(CONFIG_X86_LOCAL_APIC) += apic.o apic_noop.o probe_$(BITS).o ipi.o | 5 | obj-$(CONFIG_X86_LOCAL_APIC) += apic.o apic_noop.o probe_$(BITS).o ipi.o |
| 6 | ifneq ($(CONFIG_HARDLOCKUP_DETECTOR),y) | 6 | obj-y += hw_nmi.o |
| 7 | obj-$(CONFIG_X86_LOCAL_APIC) += nmi.o | ||
| 8 | endif | ||
| 9 | obj-$(CONFIG_HARDLOCKUP_DETECTOR) += hw_nmi.o | ||
| 10 | 7 | ||
| 11 | obj-$(CONFIG_X86_IO_APIC) += io_apic.o | 8 | obj-$(CONFIG_X86_IO_APIC) += io_apic.o |
| 12 | obj-$(CONFIG_SMP) += ipi.o | 9 | obj-$(CONFIG_SMP) += ipi.o |
diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c index cefd6942f0e..b68b1746001 100644 --- a/arch/x86/kernel/apic/hw_nmi.c +++ b/arch/x86/kernel/apic/hw_nmi.c | |||
| @@ -20,12 +20,14 @@ | |||
| 20 | /* For reliability, we're prepared to waste bits here. */ | 20 | /* For reliability, we're prepared to waste bits here. */ |
| 21 | static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly; | 21 | static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly; |
| 22 | 22 | ||
| 23 | #ifdef CONFIG_HARDLOCKUP_DETECTOR | ||
| 23 | u64 hw_nmi_get_sample_period(void) | 24 | u64 hw_nmi_get_sample_period(void) |
| 24 | { | 25 | { |
| 25 | return (u64)(cpu_khz) * 1000 * 60; | 26 | return (u64)(cpu_khz) * 1000 * 60; |
| 26 | } | 27 | } |
| 28 | #endif | ||
| 27 | 29 | ||
| 28 | #ifdef ARCH_HAS_NMI_WATCHDOG | 30 | #ifdef arch_trigger_all_cpu_backtrace |
| 29 | void arch_trigger_all_cpu_backtrace(void) | 31 | void arch_trigger_all_cpu_backtrace(void) |
| 30 | { | 32 | { |
| 31 | int i; | 33 | int i; |
| @@ -95,8 +97,6 @@ early_initcall(register_trigger_all_cpu_backtrace); | |||
| 95 | #if defined(CONFIG_X86_LOCAL_APIC) | 97 | #if defined(CONFIG_X86_LOCAL_APIC) |
| 96 | unsigned int nmi_watchdog = NMI_NONE; | 98 | unsigned int nmi_watchdog = NMI_NONE; |
| 97 | EXPORT_SYMBOL(nmi_watchdog); | 99 | EXPORT_SYMBOL(nmi_watchdog); |
| 98 | void acpi_nmi_enable(void) { return; } | ||
| 99 | void acpi_nmi_disable(void) { return; } | ||
| 100 | #endif | 100 | #endif |
| 101 | atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ | 101 | atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ |
| 102 | EXPORT_SYMBOL(nmi_active); | 102 | EXPORT_SYMBOL(nmi_active); |
diff --git a/arch/x86/kernel/apic/nmi.c b/arch/x86/kernel/apic/nmi.c deleted file mode 100644 index c90041ccb74..00000000000 --- a/arch/x86/kernel/apic/nmi.c +++ /dev/null | |||
| @@ -1,567 +0,0 @@ | |||
| 1 | /* | ||
| 2 | * NMI watchdog support on APIC systems | ||
| 3 | * | ||
| 4 | * Started by Ingo Molnar <mingo@redhat.com> | ||
| 5 | * | ||
| 6 | * Fixes: | ||
| 7 | * Mikael Pettersson : AMD K7 support for local APIC NMI watchdog. | ||
| 8 | * Mikael Pettersson : Power Management for local APIC NMI watchdog. | ||
| 9 | * Mikael Pettersson : Pentium 4 support for local APIC NMI watchdog. | ||
| 10 | * Pavel Machek and | ||
| 11 | * Mikael Pettersson : PM converted to driver model. Disable/enable API. | ||
| 12 | */ | ||
| 13 | |||
| 14 | #include <asm/apic.h> | ||
| 15 | |||
| 16 | #include <linux/nmi.h> | ||
| 17 | #include <linux/mm.h> | ||
| 18 | #include <linux/delay.h> | ||
| 19 | #include <linux/interrupt.h> | ||
| 20 | #include <linux/module.h> | ||
| 21 | #include <linux/slab.h> | ||
| 22 | #include <linux/sysdev.h> | ||
| 23 | #include <linux/sysctl.h> | ||
| 24 | #include <linux/percpu.h> | ||
| 25 | #include <linux/kprobes.h> | ||
| 26 | #include <linux/cpumask.h> | ||
| 27 | #include <linux/kernel_stat.h> | ||
| 28 | #include <linux/kdebug.h> | ||
| 29 | #include <linux/smp.h> | ||
| 30 | |||
| 31 | #include <asm/i8259.h> | ||
| 32 | #include <asm/io_apic.h> | ||
| 33 | #include <asm/proto.h> | ||
| 34 | #include <asm/timer.h> | ||
| 35 | |||
| 36 | #include <asm/mce.h> | ||
| 37 | |||
| 38 | #include <asm/mach_traps.h> | ||
| 39 | |||
| 40 | int unknown_nmi_panic; | ||
| 41 | int nmi_watchdog_enabled; | ||
| 42 | |||
| 43 | /* For reliability, we're prepared to waste bits here. */ | ||
| 44 | static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly; | ||
| 45 | |||
| 46 | /* nmi_active: | ||
| 47 | * >0: the lapic NMI watchdog is active, but can be disabled | ||
| 48 | * <0: the lapic NMI watchdog has not been set up, and cannot | ||
| 49 | * be enabled | ||
| 50 | * 0: the lapic NMI watchdog is disabled, but can be enabled | ||
| 51 | */ | ||
| 52 | atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ | ||
| 53 | EXPORT_SYMBOL(nmi_active); | ||
| 54 | |||
| 55 | unsigned int nmi_watchdog = NMI_NONE; | ||
| 56 | EXPORT_SYMBOL(nmi_watchdog); | ||
| 57 | |||
| 58 | static int panic_on_timeout; | ||
| 59 | |||
| 60 | static unsigned int nmi_hz = HZ; | ||
| 61 | static DEFINE_PER_CPU(short, wd_enabled); | ||
| 62 | static int endflag __initdata; | ||
| 63 | |||
| 64 | static inline unsigned int get_nmi_count(int cpu) | ||
| 65 | { | ||
| 66 | return per_cpu(irq_stat, cpu).__nmi_count; | ||
| 67 | } | ||
| 68 | |||
| 69 | static inline int mce_in_progress(void) | ||
| 70 | { | ||
| 71 | #if defined(CONFIG_X86_MCE) | ||
| 72 | return atomic_read(&mce_entry) > 0; | ||
| 73 | #endif | ||
| 74 | return 0; | ||
| 75 | } | ||
| 76 | |||
| 77 | /* | ||
| 78 | * Take the local apic timer and PIT/HPET into account. We don't | ||
| 79 | * know which one is active, when we have highres/dyntick on | ||
| 80 | */ | ||
| 81 | static inline unsigned int get_timer_irqs(int cpu) | ||
| 82 | { | ||
| 83 | return per_cpu(irq_stat, cpu).apic_timer_irqs + | ||
| 84 | per_cpu(irq_stat, cpu).irq0_irqs; | ||
| 85 | } | ||
| 86 | |||
| 87 | #ifdef CONFIG_SMP | ||
| 88 | /* | ||
| 89 | * The performance counters used by NMI_LOCAL_APIC don't trigger when | ||
| 90 | * the CPU is idle. To make sure the NMI watchdog really ticks on all | ||
| 91 | * CPUs during the test make them busy. | ||
| 92 | */ | ||
| 93 | static __init void nmi_cpu_busy(void *data) | ||
| 94 | { | ||
| 95 | local_irq_enable_in_hardirq(); | ||
| 96 | /* | ||
| 97 | * Intentionally don't use cpu_relax here. This is | ||
| 98 | * to make sure that the performance counter really ticks, | ||
| 99 | * even if there is a simulator or similar that catches the | ||
| 100 | * pause instruction. On a real HT machine this is fine because | ||
| 101 | * all other CPUs are busy with "useless" delay loops and don't | ||
| 102 | * care if they get somewhat less cycles. | ||
| 103 | */ | ||
| 104 | while (endflag == 0) | ||
| 105 | mb(); | ||
| 106 | } | ||
| 107 | #endif | ||
| 108 | |||
| 109 | static void report_broken_nmi(int cpu, unsigned int *prev_nmi_count) | ||
| 110 | { | ||
| 111 | printk(KERN_CONT "\n"); | ||
| 112 | |||
| 113 | printk(KERN_WARNING | ||
| 114 | "WARNING: CPU#%d: NMI appears to be stuck (%d->%d)!\n", | ||
| 115 | cpu, prev_nmi_count[cpu], get_nmi_count(cpu)); | ||
| 116 | |||
| 117 | printk(KERN_WARNING | ||
| 118 | "Please report this to bugzilla.kernel.org,\n"); | ||
| 119 | printk(KERN_WARNING | ||
| 120 | "and attach the output of the 'dmesg' command.\n"); | ||
| 121 | |||
| 122 | per_cpu(wd_enabled, cpu) = 0; | ||
| 123 | atomic_dec(&nmi_active); | ||
| 124 | } | ||
| 125 | |||
| 126 | static void __acpi_nmi_disable(void *__unused) | ||
| 127 | { | ||
| 128 | apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); | ||
| 129 | } | ||
| 130 | |||
| 131 | int __init check_nmi_watchdog(void) | ||
| 132 | { | ||
| 133 | unsigned int *prev_nmi_count; | ||
| 134 | int cpu; | ||
| 135 | |||
| 136 | if (!nmi_watchdog_active() || !atomic_read(&nmi_active)) | ||
| 137 | return 0; | ||
| 138 | |||
| 139 | prev_nmi_count = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); | ||
| 140 | if (!prev_nmi_count) | ||
| 141 | goto error; | ||
| 142 | |||
| 143 | printk(KERN_INFO "Testing NMI watchdog ... "); | ||
| 144 | |||
| 145 | #ifdef CONFIG_SMP | ||
| 146 | if (nmi_watchdog == NMI_LOCAL_APIC) | ||
| 147 | smp_call_function(nmi_cpu_busy, (void *)&endflag, 0); | ||
| 148 | #endif | ||
| 149 | |||
| 150 | for_each_possible_cpu(cpu) | ||
| 151 | prev_nmi_count[cpu] = get_nmi_count(cpu); | ||
| 152 | local_irq_enable(); | ||
| 153 | mdelay((20 * 1000) / nmi_hz); /* wait 20 ticks */ | ||
| 154 | |||
| 155 | for_each_online_cpu(cpu) { | ||
| 156 | if (!per_cpu(wd_enabled, cpu)) | ||
| 157 | continue; | ||
| 158 | if (get_nmi_count(cpu) - prev_nmi_count[cpu] <= 5) | ||
| 159 | report_broken_nmi(cpu, prev_nmi_count); | ||
| 160 | } | ||
| 161 | endflag = 1; | ||
| 162 | if (!atomic_read(&nmi_active)) { | ||
| 163 | kfree(prev_nmi_count); | ||
| 164 | atomic_set(&nmi_active, -1); | ||
| 165 | goto error; | ||
| 166 | } | ||
| 167 | printk("OK.\n"); | ||
| 168 | |||
| 169 | /* | ||
| 170 | * now that we know it works we can reduce NMI frequency to | ||
| 171 | * something more reasonable; makes a difference in some configs | ||
| 172 | */ | ||
| 173 | if (nmi_watchdog == NMI_LOCAL_APIC) | ||
| 174 | nmi_hz = lapic_adjust_nmi_hz(1); | ||
| 175 | |||
| 176 | kfree(prev_nmi_count); | ||
| 177 | return 0; | ||
| 178 | error: | ||
| 179 | if (nmi_watchdog == NMI_IO_APIC) { | ||
| 180 | if (!timer_through_8259) | ||
| 181 | legacy_pic->mask(0); | ||
| 182 | on_each_cpu(__acpi_nmi_disable, NULL, 1); | ||
| 183 | } | ||
| 184 | |||
| 185 | #ifdef CONFIG_X86_32 | ||
| 186 | timer_ack = 0; | ||
| 187 | #endif | ||
| 188 | return -1; | ||
| 189 | } | ||
| 190 | |||
| 191 | static int __init setup_nmi_watchdog(char *str) | ||
| 192 | { | ||
| 193 | unsigned int nmi; | ||
| 194 | |||
| 195 | if (!strncmp(str, "panic", 5)) { | ||
| 196 | panic_on_timeout = 1; | ||
| 197 | str = strchr(str, ','); | ||
| 198 | if (!str) | ||
| 199 | return 1; | ||
| 200 | ++str; | ||
| 201 | } | ||
| 202 | |||
| 203 | if (!strncmp(str, "lapic", 5)) | ||
| 204 | nmi_watchdog = NMI_LOCAL_APIC; | ||
| 205 | else if (!strncmp(str, "ioapic", 6)) | ||
| 206 | nmi_watchdog = NMI_IO_APIC; | ||
| 207 | else { | ||
| 208 | get_option(&str, &nmi); | ||
| 209 | if (nmi >= NMI_INVALID) | ||
| 210 | return 0; | ||
| 211 | nmi_watchdog = nmi; | ||
| 212 | } | ||
| 213 | |||
| 214 | return 1; | ||
| 215 | } | ||
| 216 | __setup("nmi_watchdog=", setup_nmi_watchdog); | ||
| 217 | |||
| 218 | /* | ||
| 219 | * Suspend/resume support | ||
| 220 | */ | ||
| 221 | #ifdef CONFIG_PM | ||
| 222 | |||
| 223 | static int nmi_pm_active; /* nmi_active before suspend */ | ||
| 224 | |||
| 225 | static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state) | ||
| 226 | { | ||
| 227 | /* only CPU0 goes here, other CPUs should be offline */ | ||
| 228 | nmi_pm_active = atomic_read(&nmi_active); | ||
| 229 | stop_apic_nmi_watchdog(NULL); | ||
| 230 | BUG_ON(atomic_read(&nmi_active) != 0); | ||
| 231 | return 0; | ||
| 232 | } | ||
| 233 | |||
| 234 | static int lapic_nmi_resume(struct sys_device *dev) | ||
| 235 | { | ||
| 236 | /* only CPU0 goes here, other CPUs should be offline */ | ||
| 237 | if (nmi_pm_active > 0) { | ||
| 238 | setup_apic_nmi_watchdog(NULL); | ||
| 239 | touch_nmi_watchdog(); | ||
| 240 | } | ||
| 241 | return 0; | ||
| 242 | } | ||
| 243 | |||
| 244 | static struct sysdev_class nmi_sysclass = { | ||
| 245 | .name = "lapic_nmi", | ||
| 246 | .resume = lapic_nmi_resume, | ||
| 247 | .suspend = lapic_nmi_suspend, | ||
| 248 | }; | ||
| 249 | |||
| 250 | static struct sys_device device_lapic_nmi = { | ||
| 251 | .id = 0, | ||
| 252 | .cls = &nmi_sysclass, | ||
| 253 | }; | ||
| 254 | |||
| 255 | static int __init init_lapic_nmi_sysfs(void) | ||
| 256 | { | ||
| 257 | int error; | ||
| 258 | |||
| 259 | /* | ||
| 260 | * should really be a BUG_ON but b/c this is an | ||
| 261 | * init call, it just doesn't work. -dcz | ||
| 262 | */ | ||
| 263 | if (nmi_watchdog != NMI_LOCAL_APIC) | ||
| 264 | return 0; | ||
| 265 | |||
| 266 | if (atomic_read(&nmi_active) < 0) | ||
| 267 | return 0; | ||
| 268 | |||
| 269 | error = sysdev_class_register(&nmi_sysclass); | ||
| 270 | if (!error) | ||
| 271 | error = sysdev_register(&device_lapic_nmi); | ||
| 272 | return error; | ||
| 273 | } | ||
| 274 | |||
| 275 | /* must come after the local APIC's device_initcall() */ | ||
| 276 | late_initcall(init_lapic_nmi_sysfs); | ||
| 277 | |||
| 278 | #endif /* CONFIG_PM */ | ||
| 279 | |||
| 280 | static void __acpi_nmi_enable(void *__unused) | ||
| 281 | { | ||
| 282 | apic_write(APIC_LVT0, APIC_DM_NMI); | ||
| 283 | } | ||
| 284 | |||
| 285 | /* | ||
| 286 | * Enable timer based NMIs on all CPUs: | ||
| 287 | */ | ||
| 288 | void acpi_nmi_enable(void) | ||
| 289 | { | ||
| 290 | if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) | ||
| 291 | on_each_cpu(__acpi_nmi_enable, NULL, 1); | ||
| 292 | } | ||
| 293 | |||
| 294 | /* | ||
| 295 | * Disable timer based NMIs on all CPUs: | ||
| 296 | */ | ||
| 297 | void acpi_nmi_disable(void) | ||
| 298 | { | ||
| 299 | if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) | ||
| 300 | on_each_cpu(__acpi_nmi_disable, NULL, 1); | ||
| 301 | } | ||
| 302 | |||
| 303 | /* | ||
| 304 | * This function is called as soon the LAPIC NMI watchdog driver has everything | ||
| 305 | * in place and it's ready to check if the NMIs belong to the NMI watchdog | ||
| 306 | */ | ||
| 307 | void cpu_nmi_set_wd_enabled(void) | ||
| 308 | { | ||
| 309 | __get_cpu_var(wd_enabled) = 1; | ||
| 310 | } | ||
| 311 | |||
| 312 | void setup_apic_nmi_watchdog(void *unused) | ||
| 313 | { | ||
| 314 | if (__get_cpu_var(wd_enabled)) | ||
| 315 | return; | ||
| 316 | |||
| 317 | /* cheap hack to support suspend/resume */ | ||
| 318 | /* if cpu0 is not active neither should the other cpus */ | ||
| 319 | if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0) | ||
| 320 | return; | ||
| 321 | |||
| 322 | switch (nmi_watchdog) { | ||
| 323 | case NMI_LOCAL_APIC: | ||
| 324 | if (lapic_watchdog_init(nmi_hz) < 0) { | ||
| 325 | __get_cpu_var(wd_enabled) = 0; | ||
| 326 | return; | ||
| 327 | } | ||
| 328 | /* FALL THROUGH */ | ||
| 329 | case NMI_IO_APIC: | ||
| 330 | __get_cpu_var(wd_enabled) = 1; | ||
| 331 | atomic_inc(&nmi_active); | ||
| 332 | } | ||
| 333 | } | ||
| 334 | |||
| 335 | void stop_apic_nmi_watchdog(void *unused) | ||
| 336 | { | ||
| 337 | /* only support LOCAL and IO APICs for now */ | ||
| 338 | if (!nmi_watchdog_active()) | ||
| 339 | return; | ||
| 340 | if (__get_cpu_var(wd_enabled) == 0) | ||
| 341 | return; | ||
| 342 | if (nmi_watchdog == NMI_LOCAL_APIC) | ||
| 343 | lapic_watchdog_stop(); | ||
| 344 | else | ||
| 345 | __acpi_nmi_disable(NULL); | ||
| 346 | __get_cpu_var(wd_enabled) = 0; | ||
| 347 | atomic_dec(&nmi_active); | ||
| 348 | } | ||
| 349 | |||
| 350 | /* | ||
| 351 | * the best way to detect whether a CPU has a 'hard lockup' problem | ||
| 352 | * is to check it's local APIC timer IRQ counts. If they are not | ||
| 353 | * changing then that CPU has some problem. | ||
| 354 | * | ||
| 355 | * as these watchdog NMI IRQs are generated on every CPU, we only | ||
| 356 | * have to check the current processor. | ||
| 357 | * | ||
| 358 | * since NMIs don't listen to _any_ locks, we have to be extremely | ||
| 359 | * careful not to rely on unsafe variables. The printk might lock | ||
| 360 | * up though, so we have to break up any console locks first ... | ||
| 361 | * [when there will be more tty-related locks, break them up here too!] | ||
| 362 | */ | ||
| 363 | |||
| 364 | static DEFINE_PER_CPU(unsigned, last_irq_sum); | ||
| 365 | static DEFINE_PER_CPU(long, alert_counter); | ||
| 366 | static DEFINE_PER_CPU(int, nmi_touch); | ||
| 367 | |||
| 368 | void touch_nmi_watchdog(void) | ||
| 369 | { | ||
| 370 | if (nmi_watchdog_active()) { | ||
| 371 | unsigned cpu; | ||
| 372 | |||
| 373 | /* | ||
| 374 | * Tell other CPUs to reset their alert counters. We cannot | ||
| 375 | * do it ourselves because the alert count increase is not | ||
| 376 | * atomic. | ||
| 377 | */ | ||
| 378 | for_each_present_cpu(cpu) { | ||
| 379 | if (per_cpu(nmi_touch, cpu) != 1) | ||
| 380 | per_cpu(nmi_touch, cpu) = 1; | ||
| 381 | } | ||
| 382 | } | ||
| 383 | |||
| 384 | /* | ||
| 385 | * Tickle the softlockup detector too: | ||
| 386 | */ | ||
| 387 | touch_softlockup_watchdog(); | ||
| 388 | } | ||
| 389 | EXPORT_SYMBOL(touch_nmi_watchdog); | ||
| 390 | |||
| 391 | notrace __kprobes int | ||
| 392 | nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) | ||
| 393 | { | ||
| 394 | /* | ||
| 395 | * Since current_thread_info()-> is always on the stack, and we | ||
| 396 | * always switch the stack NMI-atomically, it's safe to use | ||
| 397 | * smp_processor_id(). | ||
| 398 | */ | ||
| 399 | unsigned int sum; | ||
| 400 | int touched = 0; | ||
| 401 | int cpu = smp_processor_id(); | ||
| 402 | int rc = 0; | ||
| 403 | |||
| 404 | sum = get_timer_irqs(cpu); | ||
| 405 | |||
| 406 | if (__get_cpu_var(nmi_touch)) { | ||
| 407 | __get_cpu_var(nmi_touch) = 0; | ||
| 408 | touched = 1; | ||
| 409 | } | ||
| 410 | |||
| 411 | /* We can be called before check_nmi_watchdog, hence NULL check. */ | ||
| 412 | if (cpumask_test_cpu(cpu, to_cpumask(backtrace_mask))) { | ||
| 413 | static DEFINE_RAW_SPINLOCK(lock); /* Serialise the printks */ | ||
| 414 | |||
| 415 | raw_spin_lock(&lock); | ||
| 416 | printk(KERN_WARNING "NMI backtrace for cpu %d\n", cpu); | ||
| 417 | show_regs(regs); | ||
| 418 | dump_stack(); | ||
| 419 | raw_spin_unlock(&lock); | ||
| 420 | cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask)); | ||
| 421 | |||
| 422 | rc = 1; | ||
| 423 | } | ||
| 424 | |||
| 425 | /* Could check oops_in_progress here too, but it's safer not to */ | ||
| 426 | if (mce_in_progress()) | ||
| 427 | touched = 1; | ||
| 428 | |||
| 429 | /* if the none of the timers isn't firing, this cpu isn't doing much */ | ||
| 430 | if (!touched && __get_cpu_var(last_irq_sum) == sum) { | ||
| 431 | /* | ||
| 432 | * Ayiee, looks like this CPU is stuck ... | ||
| 433 | * wait a few IRQs (5 seconds) before doing the oops ... | ||
| 434 | */ | ||
| 435 | __this_cpu_inc(alert_counter); | ||
| 436 | if (__this_cpu_read(alert_counter) == 5 * nmi_hz) | ||
| 437 | /* | ||
| 438 | * die_nmi will return ONLY if NOTIFY_STOP happens.. | ||
| 439 | */ | ||
| 440 | die_nmi("BUG: NMI Watchdog detected LOCKUP", | ||
| 441 | regs, panic_on_timeout); | ||
| 442 | } else { | ||
| 443 | __get_cpu_var(last_irq_sum) = sum; | ||
| 444 | __this_cpu_write(alert_counter, 0); | ||
| 445 | } | ||
| 446 | |||
| 447 | /* see if the nmi watchdog went off */ | ||
| 448 | if (!__get_cpu_var(wd_enabled)) | ||
| 449 | return rc; | ||
| 450 | switch (nmi_watchdog) { | ||
| 451 | case NMI_LOCAL_APIC: | ||
| 452 | rc |= lapic_wd_event(nmi_hz); | ||
| 453 | break; | ||
| 454 | case NMI_IO_APIC: | ||
| 455 | /* | ||
| 456 | * don't know how to accurately check for this. | ||
| 457 | * just assume it was a watchdog timer interrupt | ||
| 458 | * This matches the old behaviour. | ||
| 459 | */ | ||
| 460 | rc = 1; | ||
| 461 | break; | ||
| 462 | } | ||
| 463 | return rc; | ||
| 464 | } | ||
| 465 | |||
| 466 | #ifdef CONFIG_SYSCTL | ||
| 467 | |||
| 468 | static void enable_ioapic_nmi_watchdog_single(void *unused) | ||
| 469 | { | ||
| 470 | __get_cpu_var(wd_enabled) = 1; | ||
| 471 | atomic_inc(&nmi_active); | ||
| 472 | __acpi_nmi_enable(NULL); | ||
| 473 | } | ||
| 474 | |||
| 475 | static void enable_ioapic_nmi_watchdog(void) | ||
| 476 | { | ||
| 477 | on_each_cpu(enable_ioapic_nmi_watchdog_single, NULL, 1); | ||
| 478 | touch_nmi_watchdog(); | ||
| 479 | } | ||
| 480 | |||
| 481 | static void disable_ioapic_nmi_watchdog(void) | ||
| 482 | { | ||
| 483 | on_each_cpu(stop_apic_nmi_watchdog, NULL, 1); | ||
| 484 | } | ||
| 485 | |||
| 486 | static int __init setup_unknown_nmi_panic(char *str) | ||
| 487 | { | ||
| 488 | unknown_nmi_panic = 1; | ||
| 489 | return 1; | ||
| 490 | } | ||
| 491 | __setup("unknown_nmi_panic", setup_unknown_nmi_panic); | ||
| 492 | |||
| 493 | static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) | ||
| 494 | { | ||
| 495 | unsigned char reason = get_nmi_reason(); | ||
| 496 | char buf[64]; | ||
| 497 | |||
| 498 | sprintf(buf, "NMI received for unknown reason %02x\n", reason); | ||
| 499 | die_nmi(buf, regs, 1); /* Always panic here */ | ||
| 500 | return 0; | ||
| 501 | } | ||
| 502 | |||
| 503 | /* | ||
| 504 | * proc handler for /proc/sys/kernel/nmi | ||
| 505 | */ | ||
| 506 | int proc_nmi_enabled(struct ctl_table *table, int write, | ||
| 507 | void __user *buffer, size_t *length, loff_t *ppos) | ||
| 508 | { | ||
| 509 | int old_state; | ||
| 510 | |||
| 511 | nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0; | ||
| 512 | old_state = nmi_watchdog_enabled; | ||
| 513 | proc_dointvec(table, write, buffer, length, ppos); | ||
| 514 | if (!!old_state == !!nmi_watchdog_enabled) | ||
| 515 | return 0; | ||
| 516 | |||
| 517 | if (atomic_read(&nmi_active) < 0 || !nmi_watchdog_active()) { | ||
| 518 | printk(KERN_WARNING | ||
| 519 | "NMI watchdog is permanently disabled\n"); | ||
| 520 | return -EIO; | ||
| 521 | } | ||
| 522 | |||
| 523 | if (nmi_watchdog == NMI_LOCAL_APIC) { | ||
| 524 | if (nmi_watchdog_enabled) | ||
| 525 | enable_lapic_nmi_watchdog(); | ||
| 526 | else | ||
| 527 | disable_lapic_nmi_watchdog(); | ||
| 528 | } else if (nmi_watchdog == NMI_IO_APIC) { | ||
| 529 | if (nmi_watchdog_enabled) | ||
| 530 | enable_ioapic_nmi_watchdog(); | ||
| 531 | else | ||
| 532 | disable_ioapic_nmi_watchdog(); | ||
| 533 | } else { | ||
| 534 | printk(KERN_WARNING | ||
| 535 | "NMI watchdog doesn't know what hardware to touch\n"); | ||
| 536 | return -EIO; | ||
| 537 | } | ||
| 538 | return 0; | ||
| 539 | } | ||
| 540 | |||
| 541 | #endif /* CONFIG_SYSCTL */ | ||
| 542 | |||
| 543 | int do_nmi_callback(struct pt_regs *regs, int cpu) | ||
| 544 | { | ||
| 545 | #ifdef CONFIG_SYSCTL | ||
| 546 | if (unknown_nmi_panic) | ||
| 547 | return unknown_nmi_panic_callback(regs, cpu); | ||
| 548 | #endif | ||
| 549 | return 0; | ||
| 550 | } | ||
| 551 | |||
| 552 | void arch_trigger_all_cpu_backtrace(void) | ||
| 553 | { | ||
| 554 | int i; | ||
| 555 | |||
| 556 | cpumask_copy(to_cpumask(backtrace_mask), cpu_online_mask); | ||
| 557 | |||
| 558 | printk(KERN_INFO "sending NMI to all CPUs:\n"); | ||
| 559 | apic->send_IPI_all(NMI_VECTOR); | ||
| 560 | |||
| 561 | /* Wait for up to 10 seconds for all CPUs to do the backtrace */ | ||
| 562 | for (i = 0; i < 10 * 1000; i++) { | ||
| 563 | if (cpumask_empty(to_cpumask(backtrace_mask))) | ||
| 564 | break; | ||
| 565 | mdelay(1); | ||
| 566 | } | ||
| 567 | } | ||
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index cb838ca42c9..db30d9cb9dd 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c | |||
| @@ -398,15 +398,6 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) | |||
| 398 | == NOTIFY_STOP) | 398 | == NOTIFY_STOP) |
| 399 | return; | 399 | return; |
| 400 | 400 | ||
| 401 | #ifndef CONFIG_LOCKUP_DETECTOR | ||
| 402 | /* | ||
| 403 | * Ok, so this is none of the documented NMI sources, | ||
| 404 | * so it must be the NMI watchdog. | ||
| 405 | */ | ||
| 406 | if (nmi_watchdog_tick(regs, reason)) | ||
| 407 | return; | ||
| 408 | if (!do_nmi_callback(regs, cpu)) | ||
| 409 | #endif /* !CONFIG_LOCKUP_DETECTOR */ | ||
| 410 | unknown_nmi_error(reason, regs); | 401 | unknown_nmi_error(reason, regs); |
| 411 | #else | 402 | #else |
| 412 | unknown_nmi_error(reason, regs); | 403 | unknown_nmi_error(reason, regs); |
diff --git a/include/linux/nmi.h b/include/linux/nmi.h index 06aab5eee13..0cb3e5c246d 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h | |||
| @@ -16,10 +16,7 @@ | |||
| 16 | */ | 16 | */ |
| 17 | #ifdef ARCH_HAS_NMI_WATCHDOG | 17 | #ifdef ARCH_HAS_NMI_WATCHDOG |
| 18 | #include <asm/nmi.h> | 18 | #include <asm/nmi.h> |
| 19 | extern void touch_nmi_watchdog(void); | 19 | #endif |
| 20 | extern void acpi_nmi_disable(void); | ||
| 21 | extern void acpi_nmi_enable(void); | ||
| 22 | #else | ||
| 23 | #ifndef CONFIG_HARDLOCKUP_DETECTOR | 20 | #ifndef CONFIG_HARDLOCKUP_DETECTOR |
| 24 | static inline void touch_nmi_watchdog(void) | 21 | static inline void touch_nmi_watchdog(void) |
| 25 | { | 22 | { |
| @@ -30,7 +27,6 @@ extern void touch_nmi_watchdog(void); | |||
| 30 | #endif | 27 | #endif |
| 31 | static inline void acpi_nmi_disable(void) { } | 28 | static inline void acpi_nmi_disable(void) { } |
| 32 | static inline void acpi_nmi_enable(void) { } | 29 | static inline void acpi_nmi_enable(void) { } |
| 33 | #endif | ||
| 34 | 30 | ||
| 35 | /* | 31 | /* |
| 36 | * Create trigger_all_cpu_backtrace() out of the arch-provided | 32 | * Create trigger_all_cpu_backtrace() out of the arch-provided |
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index b65bf634035..ce33e2a2afe 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c | |||
| @@ -746,22 +746,6 @@ static struct ctl_table kern_table[] = { | |||
| 746 | .extra2 = &one, | 746 | .extra2 = &one, |
| 747 | }, | 747 | }, |
| 748 | #endif | 748 | #endif |
| 749 | #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) && !defined(CONFIG_LOCKUP_DETECTOR) | ||
| 750 | { | ||
| 751 | .procname = "unknown_nmi_panic", | ||
| 752 | .data = &unknown_nmi_panic, | ||
| 753 | .maxlen = sizeof (int), | ||
| 754 | .mode = 0644, | ||
| 755 | .proc_handler = proc_dointvec, | ||
| 756 | }, | ||
| 757 | { | ||
| 758 | .procname = "nmi_watchdog", | ||
| 759 | .data = &nmi_watchdog_enabled, | ||
| 760 | .maxlen = sizeof (int), | ||
| 761 | .mode = 0644, | ||
| 762 | .proc_handler = proc_nmi_enabled, | ||
| 763 | }, | ||
| 764 | #endif | ||
| 765 | #if defined(CONFIG_X86) | 749 | #if defined(CONFIG_X86) |
| 766 | { | 750 | { |
| 767 | .procname = "panic_on_unrecovered_nmi", | 751 | .procname = "panic_on_unrecovered_nmi", |
