Commit 7687b80a authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86/MCE update from Ingo Molnar:
 "Various MCE robustness enhancements.

  One of the changes adds CMCI (Corrected Machine Check Interrupt) poll
  mode on Intel Nehalem+ CPUs, which mode is automatically entered when
  the rate of messages is too high - and exited once the storm is over.

  An MCE events storm will roughly look like this:

   [ 5342.740616] mce: [Hardware Error]: Machine check events logged
   [ 5342.746501] mce: [Hardware Error]: Machine check events logged
   [ 5342.757971] CMCI storm detected: switching to poll mode
   [ 5372.674957] CMCI storm subsided: switching to interrupt mode

  This should make such events more survivable"

* 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Provide boot argument to honour bios-set CMCI threshold
  x86, MCE: Remove unused defines
  x86, mce: Enable MCA support by default
  x86/mce: Add CMCI poll mode
  x86/mce: Make cmci_discover() quiet
  x86: mce: Remove the frozen cases in the hotplug code
  x86: mce: Split timer init
  x86: mce: Serialize mce injection
  x86: mce: Disable preemption when calling raise_local()
parents ac07f5c3 39ba5010
......@@ -50,6 +50,13 @@ Machine check
monarchtimeout:
Sets the time in us to wait for other CPUs on machine checks. 0
to disable.
mce=bios_cmci_threshold
Don't overwrite the bios-set CMCI threshold. This boot option
prevents Linux from overwriting the CMCI threshold set by the
bios. Without this option, Linux always sets the CMCI
threshold to 1. Enabling this may make memory predictive failure
analysis less effective if the bios sets thresholds for memory
errors since we will not see details for all errors.
nomce (for compatibility with i386): same as mce=off
......
......@@ -874,6 +874,7 @@ config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
config X86_MCE
bool "Machine Check / overheating reporting"
default y
---help---
Machine Check support allows the processor to notify the
kernel if it detects a problem (e.g. overheating, data corruption).
......
......@@ -116,19 +116,9 @@ struct mce_log {
/* Software defined banks */
#define MCE_EXTENDED_BANK 128
#define MCE_THERMAL_BANK MCE_EXTENDED_BANK + 0
#define K8_MCE_THRESHOLD_BASE (MCE_EXTENDED_BANK + 1) /* MCE_AMD */
#define K8_MCE_THRESHOLD_BANK_0 (MCE_THRESHOLD_BASE + 0 * 9)
#define K8_MCE_THRESHOLD_BANK_1 (MCE_THRESHOLD_BASE + 1 * 9)
#define K8_MCE_THRESHOLD_BANK_2 (MCE_THRESHOLD_BASE + 2 * 9)
#define K8_MCE_THRESHOLD_BANK_3 (MCE_THRESHOLD_BASE + 3 * 9)
#define K8_MCE_THRESHOLD_BANK_4 (MCE_THRESHOLD_BASE + 4 * 9)
#define K8_MCE_THRESHOLD_BANK_5 (MCE_THRESHOLD_BASE + 5 * 9)
#define K8_MCE_THRESHOLD_DRAM_ECC (MCE_THRESHOLD_BANK_4 + 0)
#define K8_MCE_THRESHOLD_BASE (MCE_EXTENDED_BANK + 1)
#ifdef __KERNEL__
extern void mce_register_decode_chain(struct notifier_block *nb);
extern void mce_unregister_decode_chain(struct notifier_block *nb);
......@@ -171,6 +161,7 @@ DECLARE_PER_CPU(struct device *, mce_device);
#ifdef CONFIG_X86_MCE_INTEL
extern int mce_cmci_disabled;
extern int mce_ignore_ce;
extern int mce_bios_cmci_threshold;
void mce_intel_feature_init(struct cpuinfo_x86 *c);
void cmci_clear(void);
void cmci_reenable(void);
......
......@@ -78,6 +78,7 @@ static void raise_exception(struct mce *m, struct pt_regs *pregs)
}
static cpumask_var_t mce_inject_cpumask;
static DEFINE_MUTEX(mce_inject_mutex);
static int mce_raise_notify(unsigned int cmd, struct pt_regs *regs)
{
......@@ -194,7 +195,11 @@ static void raise_mce(struct mce *m)
put_online_cpus();
} else
#endif
{
preempt_disable();
raise_local();
preempt_enable();
}
}
/* Error injection interface */
......@@ -225,7 +230,10 @@ static ssize_t mce_write(struct file *filp, const char __user *ubuf,
* so do it a jiffie or two later everywhere.
*/
schedule_timeout(2);
mutex_lock(&mce_inject_mutex);
raise_mce(&m);
mutex_unlock(&mce_inject_mutex);
return usize;
}
......
......@@ -28,6 +28,18 @@ extern int mce_ser;
extern struct mce_bank *mce_banks;
#ifdef CONFIG_X86_MCE_INTEL
unsigned long mce_intel_adjust_timer(unsigned long interval);
void mce_intel_cmci_poll(void);
void mce_intel_hcpu_update(unsigned long cpu);
#else
# define mce_intel_adjust_timer mce_adjust_timer_default
static inline void mce_intel_cmci_poll(void) { }
static inline void mce_intel_hcpu_update(unsigned long cpu) { }
#endif
void mce_timer_kick(unsigned long interval);
#ifdef CONFIG_ACPI_APEI
int apei_write_mce(struct mce *m);
ssize_t apei_read_mce(struct mce *m, u64 *record_id);
......
......@@ -83,6 +83,7 @@ static int mce_dont_log_ce __read_mostly;
int mce_cmci_disabled __read_mostly;
int mce_ignore_ce __read_mostly;
int mce_ser __read_mostly;
int mce_bios_cmci_threshold __read_mostly;
struct mce_bank *mce_banks __read_mostly;
......@@ -1266,6 +1267,14 @@ static unsigned long check_interval = 5 * 60; /* 5 minutes */
static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */
static DEFINE_PER_CPU(struct timer_list, mce_timer);
static unsigned long mce_adjust_timer_default(unsigned long interval)
{
return interval;
}
static unsigned long (*mce_adjust_timer)(unsigned long interval) =
mce_adjust_timer_default;
static void mce_timer_fn(unsigned long data)
{
struct timer_list *t = &__get_cpu_var(mce_timer);
......@@ -1276,6 +1285,7 @@ static void mce_timer_fn(unsigned long data)
if (mce_available(__this_cpu_ptr(&cpu_info))) {
machine_check_poll(MCP_TIMESTAMP,
&__get_cpu_var(mce_poll_banks));
mce_intel_cmci_poll();
}
/*
......@@ -1283,14 +1293,38 @@ static void mce_timer_fn(unsigned long data)
* polling interval, otherwise increase the polling interval.
*/
iv = __this_cpu_read(mce_next_interval);
if (mce_notify_irq())
if (mce_notify_irq()) {
iv = max(iv / 2, (unsigned long) HZ/100);
else
} else {
iv = min(iv * 2, round_jiffies_relative(check_interval * HZ));
iv = mce_adjust_timer(iv);
}
__this_cpu_write(mce_next_interval, iv);
/* Might have become 0 after CMCI storm subsided */
if (iv) {
t->expires = jiffies + iv;
add_timer_on(t, smp_processor_id());
}
}
t->expires = jiffies + iv;
add_timer_on(t, smp_processor_id());
/*
* Ensure that the timer is firing in @interval from now.
*/
void mce_timer_kick(unsigned long interval)
{
struct timer_list *t = &__get_cpu_var(mce_timer);
unsigned long when = jiffies + interval;
unsigned long iv = __this_cpu_read(mce_next_interval);
if (timer_pending(t)) {
if (time_before(when, t->expires))
mod_timer_pinned(t, when);
} else {
t->expires = round_jiffies(when);
add_timer_on(t, smp_processor_id());
}
if (interval < iv)
__this_cpu_write(mce_next_interval, interval);
}
/* Must not be called in IRQ context where del_timer_sync() can deadlock */
......@@ -1585,6 +1619,7 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
switch (c->x86_vendor) {
case X86_VENDOR_INTEL:
mce_intel_feature_init(c);
mce_adjust_timer = mce_intel_adjust_timer;
break;
case X86_VENDOR_AMD:
mce_amd_feature_init(c);
......@@ -1594,23 +1629,28 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
}
}
static void __mcheck_cpu_init_timer(void)
static void mce_start_timer(unsigned int cpu, struct timer_list *t)
{
struct timer_list *t = &__get_cpu_var(mce_timer);
unsigned long iv = check_interval * HZ;
unsigned long iv = mce_adjust_timer(check_interval * HZ);
setup_timer(t, mce_timer_fn, smp_processor_id());
__this_cpu_write(mce_next_interval, iv);
if (mce_ignore_ce)
if (mce_ignore_ce || !iv)
return;
__this_cpu_write(mce_next_interval, iv);
if (!iv)
return;
t->expires = round_jiffies(jiffies + iv);
add_timer_on(t, smp_processor_id());
}
static void __mcheck_cpu_init_timer(void)
{
struct timer_list *t = &__get_cpu_var(mce_timer);
unsigned int cpu = smp_processor_id();
setup_timer(t, mce_timer_fn, cpu);
mce_start_timer(cpu, t);
}
/* Handle unconfigured int18 (should never happen) */
static void unexpected_machine_check(struct pt_regs *regs, long error_code)
{
......@@ -1907,6 +1947,7 @@ static struct miscdevice mce_chrdev_device = {
* check, or 0 to not wait
* mce=bootlog Log MCEs from before booting. Disabled by default on AMD.
* mce=nobootlog Don't log MCEs from before booting.
* mce=bios_cmci_threshold Don't program the CMCI threshold
*/
static int __init mcheck_enable(char *str)
{
......@@ -1926,6 +1967,8 @@ static int __init mcheck_enable(char *str)
mce_ignore_ce = 1;
else if (!strcmp(str, "bootlog") || !strcmp(str, "nobootlog"))
mce_bootlog = (str[0] == 'b');
else if (!strcmp(str, "bios_cmci_threshold"))
mce_bios_cmci_threshold = 1;
else if (isdigit(str[0])) {
get_option(&str, &tolerant);
if (*str == ',') {
......@@ -2166,6 +2209,11 @@ static struct dev_ext_attribute dev_attr_cmci_disabled = {
&mce_cmci_disabled
};
static struct dev_ext_attribute dev_attr_bios_cmci_threshold = {
__ATTR(bios_cmci_threshold, 0444, device_show_int, NULL),
&mce_bios_cmci_threshold
};
static struct device_attribute *mce_device_attrs[] = {
&dev_attr_tolerant.attr,
&dev_attr_check_interval.attr,
......@@ -2174,6 +2222,7 @@ static struct device_attribute *mce_device_attrs[] = {
&dev_attr_dont_log_ce.attr,
&dev_attr_ignore_ce.attr,
&dev_attr_cmci_disabled.attr,
&dev_attr_bios_cmci_threshold.attr,
NULL
};
......@@ -2294,38 +2343,33 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
unsigned int cpu = (unsigned long)hcpu;
struct timer_list *t = &per_cpu(mce_timer, cpu);
switch (action) {
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
mce_device_create(cpu);
if (threshold_cpu_callback)
threshold_cpu_callback(action, cpu);
break;
case CPU_DEAD:
case CPU_DEAD_FROZEN:
if (threshold_cpu_callback)
threshold_cpu_callback(action, cpu);
mce_device_remove(cpu);
mce_intel_hcpu_update(cpu);
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
del_timer_sync(t);
smp_call_function_single(cpu, mce_disable_cpu, &action, 1);
del_timer_sync(t);
break;
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
if (!mce_ignore_ce && check_interval) {
t->expires = round_jiffies(jiffies +
per_cpu(mce_next_interval, cpu));
add_timer_on(t, cpu);
}
smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
mce_start_timer(cpu, t);
break;
case CPU_POST_DEAD:
}
if (action == CPU_POST_DEAD) {
/* intentionally ignoring frozen here */
cmci_rediscover(cpu);
break;
}
return NOTIFY_OK;
}
......
......@@ -15,6 +15,8 @@
#include <asm/msr.h>
#include <asm/mce.h>
#include "mce-internal.h"
/*
* Support for Intel Correct Machine Check Interrupts. This allows
* the CPU to raise an interrupt when a corrected machine check happened.
......@@ -30,7 +32,22 @@ static DEFINE_PER_CPU(mce_banks_t, mce_banks_owned);
*/
static DEFINE_RAW_SPINLOCK(cmci_discover_lock);
#define CMCI_THRESHOLD 1
#define CMCI_THRESHOLD 1
#define CMCI_POLL_INTERVAL (30 * HZ)
#define CMCI_STORM_INTERVAL (1 * HZ)
#define CMCI_STORM_THRESHOLD 15
static DEFINE_PER_CPU(unsigned long, cmci_time_stamp);
static DEFINE_PER_CPU(unsigned int, cmci_storm_cnt);
static DEFINE_PER_CPU(unsigned int, cmci_storm_state);
enum {
CMCI_STORM_NONE,
CMCI_STORM_ACTIVE,
CMCI_STORM_SUBSIDED,
};
static atomic_t cmci_storm_on_cpus;
static int cmci_supported(int *banks)
{
......@@ -53,6 +70,93 @@ static int cmci_supported(int *banks)
return !!(cap & MCG_CMCI_P);
}
void mce_intel_cmci_poll(void)
{
if (__this_cpu_read(cmci_storm_state) == CMCI_STORM_NONE)
return;
machine_check_poll(MCP_TIMESTAMP, &__get_cpu_var(mce_banks_owned));
}
void mce_intel_hcpu_update(unsigned long cpu)
{
if (per_cpu(cmci_storm_state, cpu) == CMCI_STORM_ACTIVE)
atomic_dec(&cmci_storm_on_cpus);
per_cpu(cmci_storm_state, cpu) = CMCI_STORM_NONE;
}
unsigned long mce_intel_adjust_timer(unsigned long interval)
{
int r;
if (interval < CMCI_POLL_INTERVAL)
return interval;
switch (__this_cpu_read(cmci_storm_state)) {
case CMCI_STORM_ACTIVE:
/*
* We switch back to interrupt mode once the poll timer has
* silenced itself. That means no events recorded and the
* timer interval is back to our poll interval.
*/
__this_cpu_write(cmci_storm_state, CMCI_STORM_SUBSIDED);
r = atomic_sub_return(1, &cmci_storm_on_cpus);
if (r == 0)
pr_notice("CMCI storm subsided: switching to interrupt mode\n");
/* FALLTHROUGH */
case CMCI_STORM_SUBSIDED:
/*
* We wait for all cpus to go back to SUBSIDED
* state. When that happens we switch back to
* interrupt mode.
*/
if (!atomic_read(&cmci_storm_on_cpus)) {
__this_cpu_write(cmci_storm_state, CMCI_STORM_NONE);
cmci_reenable();
cmci_recheck();
}
return CMCI_POLL_INTERVAL;
default:
/*
* We have shiny weather. Let the poll do whatever it
* thinks.
*/
return interval;
}
}
static bool cmci_storm_detect(void)
{
unsigned int cnt = __this_cpu_read(cmci_storm_cnt);
unsigned long ts = __this_cpu_read(cmci_time_stamp);
unsigned long now = jiffies;
int r;
if (__this_cpu_read(cmci_storm_state) != CMCI_STORM_NONE)
return true;
if (time_before_eq(now, ts + CMCI_STORM_INTERVAL)) {
cnt++;
} else {
cnt = 1;
__this_cpu_write(cmci_time_stamp, now);
}
__this_cpu_write(cmci_storm_cnt, cnt);
if (cnt <= CMCI_STORM_THRESHOLD)
return false;
cmci_clear();
__this_cpu_write(cmci_storm_state, CMCI_STORM_ACTIVE);
r = atomic_add_return(1, &cmci_storm_on_cpus);
mce_timer_kick(CMCI_POLL_INTERVAL);
if (r == 1)
pr_notice("CMCI storm detected: switching to poll mode\n");
return true;
}
/*
* The interrupt handler. This is called on every event.
* Just call the poller directly to log any events.
......@@ -61,33 +165,28 @@ static int cmci_supported(int *banks)
*/
static void intel_threshold_interrupt(void)
{
if (cmci_storm_detect())
return;
machine_check_poll(MCP_TIMESTAMP, &__get_cpu_var(mce_banks_owned));
mce_notify_irq();
}
static void print_update(char *type, int *hdr, int num)
{
if (*hdr == 0)
printk(KERN_INFO "CPU %d MCA banks", smp_processor_id());
*hdr = 1;
printk(KERN_CONT " %s:%d", type, num);
}
/*
* Enable CMCI (Corrected Machine Check Interrupt) for available MCE banks
* on this CPU. Use the algorithm recommended in the SDM to discover shared
* banks.
*/
static void cmci_discover(int banks, int boot)
static void cmci_discover(int banks)
{
unsigned long *owned = (void *)&__get_cpu_var(mce_banks_owned);
unsigned long flags;
int hdr = 0;
int i;
int bios_wrong_thresh = 0;
raw_spin_lock_irqsave(&cmci_discover_lock, flags);
for (i = 0; i < banks; i++) {
u64 val;
int bios_zero_thresh = 0;
if (test_bit(i, owned))
continue;
......@@ -96,29 +195,52 @@ static void cmci_discover(int banks, int boot)
/* Already owned by someone else? */
if (val & MCI_CTL2_CMCI_EN) {
if (test_and_clear_bit(i, owned) && !boot)
print_update("SHD", &hdr, i);
clear_bit(i, owned);
__clear_bit(i, __get_cpu_var(mce_poll_banks));
continue;
}
val &= ~MCI_CTL2_CMCI_THRESHOLD_MASK;
val |= MCI_CTL2_CMCI_EN | CMCI_THRESHOLD;
if (!mce_bios_cmci_threshold) {
val &= ~MCI_CTL2_CMCI_THRESHOLD_MASK;
val |= CMCI_THRESHOLD;
} else if (!(val & MCI_CTL2_CMCI_THRESHOLD_MASK)) {
/*
* If bios_cmci_threshold boot option was specified
* but the threshold is zero, we'll try to initialize
* it to 1.
*/
bios_zero_thresh = 1;
val |= CMCI_THRESHOLD;
}
val |= MCI_CTL2_CMCI_EN;
wrmsrl(MSR_IA32_MCx_CTL2(i), val);
rdmsrl(MSR_IA32_MCx_CTL2(i), val);
/* Did the enable bit stick? -- the bank supports CMCI */
if (val & MCI_CTL2_CMCI_EN) {
if (!test_and_set_bit(i, owned) && !boot)
print_update("CMCI", &hdr, i);
set_bit(i, owned);
__clear_bit(i, __get_cpu_var(mce_poll_banks));
/*
* We are able to set thresholds for some banks that
* had a threshold of 0. This means the BIOS has not
* set the thresholds properly or does not work with
* this boot option. Note down now and report later.
*/
if (mce_bios_cmci_threshold && bios_zero_thresh &&
(val & MCI_CTL2_CMCI_THRESHOLD_MASK))
bios_wrong_thresh = 1;
} else {
WARN_ON(!test_bit(i, __get_cpu_var(mce_poll_banks)));
}
}
raw_spin_unlock_irqrestore(&cmci_discover_lock, flags);
if (hdr)
printk(KERN_CONT "\n");
if (mce_bios_cmci_threshold && bios_wrong_thresh) {
pr_info_once(
"bios_cmci_threshold: Some banks do not have valid thresholds set\n");
pr_info_once(
"bios_cmci_threshold: Make sure your BIOS supports this boot option\n");
}
}
/*
......@@ -156,7 +278,7 @@ void cmci_clear(void)
continue;
/* Disable CMCI */
rdmsrl(MSR_IA32_MCx_CTL2(i), val);
val &= ~(MCI_CTL2_CMCI_EN|MCI_CTL2_CMCI_THRESHOLD_MASK);
val &= ~MCI_CTL2_CMCI_EN;
wrmsrl(MSR_IA32_MCx_CTL2(i), val);
__clear_bit(i, __get_cpu_var(mce_banks_owned));
}
......@@ -186,7 +308,7 @@ void cmci_rediscover(int dying)
continue;
/* Recheck banks in case CPUs don't all have the same */
if (cmci_supported(&banks))
cmci_discover(banks, 0);
cmci_discover(banks);
}
set_cpus_allowed_ptr(current, old);
......@@ -200,7 +322,7 @@ void cmci_reenable(void)
{
int banks;
if (cmci_supported(&banks))
cmci_discover(banks, 0);
cmci_discover(banks);
}
static void intel_init_cmci(void)
......@@ -211,7 +333,7 @@ static void intel_init_cmci(void)
return;
mce_threshold_vector = intel_threshold_interrupt;
cmci_discover(banks, 1);
cmci_discover(banks);
/*
* For CPU #0 this runs with still disabled APIC, but that's
* ok because only the vector is set up. We still do another
......
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