* K8 parts Copyright 2002,2003 Andi Kleen, SuSE Labs.
* Rest from unknown author(s).
* 2004 Andi Kleen. Rewrote most of it.
+ * Copyright 2008 Intel Corporation
+ * Author: Andi Kleen
*/
#include <linux/init.h>
#include <linux/ctype.h>
#include <linux/kmod.h>
#include <linux/kdebug.h>
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/mce.h>
#include <asm/idle.h>
#define MISC_MCELOG_MINOR 227
-#define NR_SYSFS_BANKS 6
+
+/*
+ * To support more than 128 would need to escape the predefined
+ * Linux defined extended banks first.
+ */
+#define MAX_NR_BANKS (MCE_EXTENDED_BANK - 1)
atomic_t mce_entry;
*/
static int tolerant = 1;
static int banks;
-static unsigned long bank[NR_SYSFS_BANKS] = { [0 ... NR_SYSFS_BANKS-1] = ~0UL };
+static u64 *bank;
static unsigned long notify_user;
static int rip_msr;
static int mce_bootlog = -1;
static DECLARE_WAIT_QUEUE_HEAD(mce_wait);
+/* Do initial initialization of a struct mce */
+void mce_setup(struct mce *m)
+{
+ memset(m, 0, sizeof(struct mce));
+ m->cpu = smp_processor_id();
+ rdtscll(m->tsc);
+}
+
/*
* Lockless MCE logging infrastructure.
* This avoids deadlocks on printk locks without having to break locks. Also
print_symbol("{%s}", m->ip);
printk("\n");
}
- printk(KERN_EMERG "TSC %Lx ", m->tsc);
+ printk(KERN_EMERG "TSC %llx ", m->tsc);
if (m->addr)
- printk("ADDR %Lx ", m->addr);
+ printk("ADDR %llx ", m->addr);
if (m->misc)
- printk("MISC %Lx ", m->misc);
+ printk("MISC %llx ", m->misc);
printk("\n");
printk(KERN_EMERG "This is not a software problem!\n");
printk(KERN_EMERG "Run through mcelog --ascii to decode "
static int mce_available(struct cpuinfo_x86 *c)
{
+ if (mce_dont_init)
+ return 0;
return cpu_has(c, X86_FEATURE_MCE) && cpu_has(c, X86_FEATURE_MCA);
}
}
/*
- * The actual machine check handler
+ * Poll for corrected events or events that happened before reset.
+ * Those are just logged through /dev/mcelog.
+ *
+ * This is executed in standard interrupt context.
+ */
+void machine_check_poll(enum mcp_flags flags)
+{
+ struct mce m;
+ int i;
+
+ mce_setup(&m);
+
+ rdmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus);
+ for (i = 0; i < banks; i++) {
+ if (!bank[i])
+ continue;
+
+ m.misc = 0;
+ m.addr = 0;
+ m.bank = i;
+ m.tsc = 0;
+
+ barrier();
+ rdmsrl(MSR_IA32_MC0_STATUS + i*4, m.status);
+ if (!(m.status & MCI_STATUS_VAL))
+ continue;
+
+ /*
+ * Uncorrected events are handled by the exception handler
+ * when it is enabled. But when the exception is disabled log
+ * everything.
+ *
+ * TBD do the same check for MCI_STATUS_EN here?
+ */
+ if ((m.status & MCI_STATUS_UC) && !(flags & MCP_UC))
+ continue;
+
+ if (m.status & MCI_STATUS_MISCV)
+ rdmsrl(MSR_IA32_MC0_MISC + i*4, m.misc);
+ if (m.status & MCI_STATUS_ADDRV)
+ rdmsrl(MSR_IA32_MC0_ADDR + i*4, m.addr);
+
+ if (!(flags & MCP_TIMESTAMP))
+ m.tsc = 0;
+ /*
+ * Don't get the IP here because it's unlikely to
+ * have anything to do with the actual error location.
+ */
+
+ mce_log(&m);
+ add_taint(TAINT_MACHINE_CHECK);
+
+ /*
+ * Clear state for this bank.
+ */
+ wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
+ }
+
+ /*
+ * Don't clear MCG_STATUS here because it's only defined for
+ * exceptions.
+ */
+}
+
+/*
+ * The actual machine check handler. This only handles real
+ * exceptions when something got corrupted coming in through int 18.
+ *
+ * This is executed in NMI context not subject to normal locking rules. This
+ * implies that most kernel services cannot be safely used. Don't even
+ * think about putting a printk in there!
*/
void do_machine_check(struct pt_regs * regs, long error_code)
{
* error.
*/
int kill_it = 0;
+ DECLARE_BITMAP(toclear, MAX_NR_BANKS);
atomic_inc(&mce_entry);
- if ((regs
- && notify_die(DIE_NMI, "machine check", regs, error_code,
+ if (notify_die(DIE_NMI, "machine check", regs, error_code,
18, SIGKILL) == NOTIFY_STOP)
- || !banks)
goto out2;
+ if (!banks)
+ goto out2;
+
+ mce_setup(&m);
- memset(&m, 0, sizeof(struct mce));
- m.cpu = smp_processor_id();
rdmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus);
/* if the restart IP is not valid, we're done for */
if (!(m.mcgstatus & MCG_STATUS_RIPV))
barrier();
for (i = 0; i < banks; i++) {
- if (i < NR_SYSFS_BANKS && !bank[i])
+ __clear_bit(i, toclear);
+ if (!bank[i])
continue;
m.misc = 0;
m.addr = 0;
m.bank = i;
- m.tsc = 0;
rdmsrl(MSR_IA32_MC0_STATUS + i*4, m.status);
if ((m.status & MCI_STATUS_VAL) == 0)
continue;
+ /*
+ * Non uncorrected errors are handled by machine_check_poll
+ * Leave them alone.
+ */
+ if ((m.status & MCI_STATUS_UC) == 0)
+ continue;
+
+ /*
+ * Set taint even when machine check was not enabled.
+ */
+ add_taint(TAINT_MACHINE_CHECK);
+
+ __set_bit(i, toclear);
+
if (m.status & MCI_STATUS_EN) {
/* if PCC was set, there's no way out */
no_way_out |= !!(m.status & MCI_STATUS_PCC);
no_way_out = 1;
kill_it = 1;
}
+ } else {
+ /*
+ * Machine check event was not enabled. Clear, but
+ * ignore.
+ */
+ continue;
}
if (m.status & MCI_STATUS_MISCV)
rdmsrl(MSR_IA32_MC0_ADDR + i*4, m.addr);
mce_get_rip(&m, regs);
- if (error_code >= 0)
- rdtscll(m.tsc);
- if (error_code != -2)
- mce_log(&m);
+ mce_log(&m);
/* Did this bank cause the exception? */
/* Assume that the bank with uncorrectable errors did it,
panicm = m;
panicm_found = 1;
}
-
- add_taint(TAINT_MACHINE_CHECK);
}
- /* Never do anything final in the polling timer */
- if (!regs)
- goto out;
-
/* If we didn't find an uncorrectable error, pick
the last one (shouldn't happen, just being safe). */
if (!panicm_found)
/* notify userspace ASAP */
set_thread_flag(TIF_MCE_NOTIFY);
- out:
/* the last thing we do is clear state */
- for (i = 0; i < banks; i++)
- wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
+ for (i = 0; i < banks; i++) {
+ if (test_bit(i, toclear))
+ wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
+ }
wrmsrl(MSR_IA32_MCG_STATUS, 0);
out2:
atomic_dec(&mce_entry);
* and historically has been the register value of the
* MSR_IA32_THERMAL_STATUS (Intel) msr.
*/
-void mce_log_therm_throt_event(unsigned int cpu, __u64 status)
+void mce_log_therm_throt_event(__u64 status)
{
struct mce m;
- memset(&m, 0, sizeof(m));
- m.cpu = cpu;
+ mce_setup(&m);
m.bank = MCE_THERMAL_BANK;
m.status = status;
- rdtscll(m.tsc);
mce_log(&m);
}
#endif /* CONFIG_X86_MCE_INTEL */
static int check_interval = 5 * 60; /* 5 minutes */
static int next_interval; /* in jiffies */
-static void mcheck_timer(struct work_struct *work);
-static DECLARE_DELAYED_WORK(mcheck_work, mcheck_timer);
+static void mcheck_timer(unsigned long);
+static DEFINE_PER_CPU(struct timer_list, mce_timer);
-static void mcheck_check_cpu(void *info)
+static void mcheck_timer(unsigned long data)
{
- if (mce_available(¤t_cpu_data))
- do_machine_check(NULL, 0);
-}
+ struct timer_list *t = &per_cpu(mce_timer, data);
-static void mcheck_timer(struct work_struct *work)
-{
- on_each_cpu(mcheck_check_cpu, NULL, 1);
+ WARN_ON(smp_processor_id() != data);
+
+ if (mce_available(¤t_cpu_data))
+ machine_check_poll(MCP_TIMESTAMP);
/*
* Alert userspace if needed. If we logged an MCE, reduce the
(int)round_jiffies_relative(check_interval*HZ));
}
- schedule_delayed_work(&mcheck_work, next_interval);
+ t->expires = jiffies + next_interval;
+ add_timer(t);
}
+static void mce_do_trigger(struct work_struct *work)
+{
+ call_usermodehelper(trigger, trigger_argv, NULL, UMH_NO_WAIT);
+}
+
+static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
+
/*
- * This is only called from process context. This is where we do
- * anything we need to alert userspace about new MCEs. This is called
- * directly from the poller and also from entry.S and idle, thanks to
- * TIF_MCE_NOTIFY.
+ * Notify the user(s) about new machine check events.
+ * Can be called from interrupt context, but not from machine check/NMI
+ * context.
*/
int mce_notify_user(void)
{
unsigned long now = jiffies;
wake_up_interruptible(&mce_wait);
- if (trigger[0])
- call_usermodehelper(trigger, trigger_argv, NULL,
- UMH_NO_WAIT);
+
+ /*
+ * There is no risk of missing notifications because
+ * work_pending is always cleared before the function is
+ * executed.
+ */
+ if (trigger[0] && !work_pending(&mce_trigger_work))
+ schedule_work(&mce_trigger_work);
if (time_after_eq(now, last_print + (check_interval*HZ))) {
last_print = now;
static __init int periodic_mcheck_init(void)
{
- next_interval = check_interval * HZ;
- if (next_interval)
- schedule_delayed_work(&mcheck_work,
- round_jiffies_relative(next_interval));
- idle_notifier_register(&mce_idle_notifier);
- return 0;
+ idle_notifier_register(&mce_idle_notifier);
+ return 0;
}
__initcall(periodic_mcheck_init);
-
/*
* Initialize Machine Checks for a CPU.
*/
-static void mce_init(void *dummy)
+static int mce_cap_init(void)
{
u64 cap;
- int i;
+ unsigned b;
rdmsrl(MSR_IA32_MCG_CAP, cap);
- banks = cap & 0xff;
- if (banks > MCE_EXTENDED_BANK) {
- banks = MCE_EXTENDED_BANK;
- printk(KERN_INFO "MCE: warning: using only %d banks\n",
- MCE_EXTENDED_BANK);
+ b = cap & 0xff;
+ if (b > MAX_NR_BANKS) {
+ printk(KERN_WARNING
+ "MCE: Using only %u machine check banks out of %u\n",
+ MAX_NR_BANKS, b);
+ b = MAX_NR_BANKS;
}
+
+ /* Don't support asymmetric configurations today */
+ WARN_ON(banks != 0 && b != banks);
+ banks = b;
+ if (!bank) {
+ bank = kmalloc(banks * sizeof(u64), GFP_KERNEL);
+ if (!bank)
+ return -ENOMEM;
+ memset(bank, 0xff, banks * sizeof(u64));
+ }
+
/* Use accurate RIP reporting if available. */
if ((cap & (1<<9)) && ((cap >> 16) & 0xff) >= 9)
rip_msr = MSR_IA32_MCG_EIP;
- /* Log the machine checks left over from the previous reset.
- This also clears all registers */
- do_machine_check(NULL, mce_bootlog ? -1 : -2);
+ return 0;
+}
+
+static void mce_init(void *dummy)
+{
+ u64 cap;
+ int i;
+
+ /*
+ * Log the machine checks left over from the previous reset.
+ */
+ machine_check_poll(MCP_UC);
set_in_cr4(X86_CR4_MCE);
+ rdmsrl(MSR_IA32_MCG_CAP, cap);
if (cap & MCG_CTL_P)
wrmsr(MSR_IA32_MCG_CTL, 0xffffffff, 0xffffffff);
for (i = 0; i < banks; i++) {
- if (i < NR_SYSFS_BANKS)
- wrmsrl(MSR_IA32_MC0_CTL+4*i, bank[i]);
- else
- wrmsrl(MSR_IA32_MC0_CTL+4*i, ~0UL);
-
+ wrmsrl(MSR_IA32_MC0_CTL+4*i, bank[i]);
wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
}
}
/* Add per CPU specific workarounds here */
-static void __cpuinit mce_cpu_quirks(struct cpuinfo_x86 *c)
+static void mce_cpu_quirks(struct cpuinfo_x86 *c)
{
/* This should be disabled by the BIOS, but isn't always */
if (c->x86_vendor == X86_VENDOR_AMD) {
- if(c->x86 == 15)
+ if (c->x86 == 15 && banks > 4)
/* disable GART TBL walk error reporting, which trips off
incorrectly with the IOMMU & 3ware & Cerberus. */
- clear_bit(10, &bank[4]);
+ clear_bit(10, (unsigned long *)&bank[4]);
if(c->x86 <= 17 && mce_bootlog < 0)
/* Lots of broken BIOS around that don't clear them
by default and leave crap in there. Don't log. */
}
}
+static void mce_init_timer(void)
+{
+ struct timer_list *t = &__get_cpu_var(mce_timer);
+
+ /* data race harmless because everyone sets to the same value */
+ if (!next_interval)
+ next_interval = check_interval * HZ;
+ if (!next_interval)
+ return;
+ setup_timer(t, mcheck_timer, smp_processor_id());
+ t->expires = round_jiffies_relative(jiffies + next_interval);
+ add_timer(t);
+}
+
/*
* Called for each booted CPU to set up machine checks.
* Must be called with preempt off.
*/
void __cpuinit mcheck_init(struct cpuinfo_x86 *c)
{
- mce_cpu_quirks(c);
+ if (!mce_available(c))
+ return;
- if (mce_dont_init ||
- !mce_available(c))
+ if (mce_cap_init() < 0) {
+ mce_dont_init = 1;
return;
+ }
+ mce_cpu_quirks(c);
mce_init(NULL);
mce_cpu_features(c);
+ mce_init_timer();
}
/*
{
unsigned long *cpu_tsc;
static DEFINE_MUTEX(mce_read_mutex);
- unsigned next;
+ unsigned prev, next;
char __user *buf = ubuf;
int i, err;
}
err = 0;
- for (i = 0; i < next; i++) {
- unsigned long start = jiffies;
-
- while (!mcelog.entry[i].finished) {
- if (time_after_eq(jiffies, start + 2)) {
- memset(mcelog.entry + i,0, sizeof(struct mce));
- goto timeout;
+ prev = 0;
+ do {
+ for (i = prev; i < next; i++) {
+ unsigned long start = jiffies;
+
+ while (!mcelog.entry[i].finished) {
+ if (time_after_eq(jiffies, start + 2)) {
+ memset(mcelog.entry + i, 0,
+ sizeof(struct mce));
+ goto timeout;
+ }
+ cpu_relax();
}
- cpu_relax();
+ smp_rmb();
+ err |= copy_to_user(buf, mcelog.entry + i,
+ sizeof(struct mce));
+ buf += sizeof(struct mce);
+timeout:
+ ;
}
- smp_rmb();
- err |= copy_to_user(buf, mcelog.entry + i, sizeof(struct mce));
- buf += sizeof(struct mce);
- timeout:
- ;
- }
- memset(mcelog.entry, 0, next * sizeof(struct mce));
- mcelog.next = 0;
+ memset(mcelog.entry + prev, 0,
+ (next - prev) * sizeof(struct mce));
+ prev = next;
+ next = cmpxchg(&mcelog.next, prev, 0);
+ } while (next != prev);
synchronize_sched();
&mce_chrdev_ops,
};
-static unsigned long old_cr4 __initdata;
-
-void __init stop_mce(void)
-{
- old_cr4 = read_cr4();
- clear_in_cr4(X86_CR4_MCE);
-}
-
-void __init restart_mce(void)
-{
- if (old_cr4 & X86_CR4_MCE)
- set_in_cr4(X86_CR4_MCE);
-}
-
/*
* Old style boot options parsing. Only for compatibility.
*/
return 1;
}
-/* mce=off disables machine check. Note you can re-enable it later
- using sysfs.
+/* mce=off disables machine check.
mce=TOLERANCELEVEL (number, see above)
mce=bootlog Log MCEs from before booting. Disabled by default on AMD.
mce=nobootlog Don't log MCEs from before booting. */
* Sysfs support
*/
+/*
+ * Disable machine checks on suspend and shutdown. We can't really handle
+ * them later.
+ */
+static int mce_disable(void)
+{
+ int i;
+
+ for (i = 0; i < banks; i++)
+ wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+ return 0;
+}
+
+static int mce_suspend(struct sys_device *dev, pm_message_t state)
+{
+ return mce_disable();
+}
+
+static int mce_shutdown(struct sys_device *dev)
+{
+ return mce_disable();
+}
+
/* On resume clear all MCE state. Don't want to see leftovers from the BIOS.
Only one CPU is active at this time, the others get readded later using
CPU hotplug. */
return 0;
}
+static void mce_cpu_restart(void *data)
+{
+ del_timer_sync(&__get_cpu_var(mce_timer));
+ if (mce_available(¤t_cpu_data))
+ mce_init(NULL);
+ mce_init_timer();
+}
+
/* Reinit MCEs after user configuration changes */
static void mce_restart(void)
{
- if (next_interval)
- cancel_delayed_work(&mcheck_work);
- /* Timer race is harmless here */
- on_each_cpu(mce_init, NULL, 1);
next_interval = check_interval * HZ;
- if (next_interval)
- schedule_delayed_work(&mcheck_work,
- round_jiffies_relative(next_interval));
+ on_each_cpu(mce_cpu_restart, NULL, 1);
}
static struct sysdev_class mce_sysclass = {
+ .suspend = mce_suspend,
+ .shutdown = mce_shutdown,
.resume = mce_resume,
.name = "machinecheck",
};
} \
static SYSDEV_ATTR(name, 0644, show_ ## name, set_ ## name);
-/*
- * TBD should generate these dynamically based on number of available banks.
- * Have only 6 contol banks in /sysfs until then.
- */
-ACCESSOR(bank0ctl,bank[0],mce_restart())
-ACCESSOR(bank1ctl,bank[1],mce_restart())
-ACCESSOR(bank2ctl,bank[2],mce_restart())
-ACCESSOR(bank3ctl,bank[3],mce_restart())
-ACCESSOR(bank4ctl,bank[4],mce_restart())
-ACCESSOR(bank5ctl,bank[5],mce_restart())
+static struct sysdev_attribute *bank_attrs;
+
+static ssize_t show_bank(struct sys_device *s, struct sysdev_attribute *attr,
+ char *buf)
+{
+ u64 b = bank[attr - bank_attrs];
+ return sprintf(buf, "%llx\n", b);
+}
+
+static ssize_t set_bank(struct sys_device *s, struct sysdev_attribute *attr,
+ const char *buf, size_t siz)
+{
+ char *end;
+ u64 new = simple_strtoull(buf, &end, 0);
+ if (end == buf)
+ return -EINVAL;
+ bank[attr - bank_attrs] = new;
+ mce_restart();
+ return end-buf;
+}
static ssize_t show_trigger(struct sys_device *s, struct sysdev_attribute *attr,
char *buf)
static SYSDEV_INT_ATTR(tolerant, 0644, tolerant);
ACCESSOR(check_interval,check_interval,mce_restart())
static struct sysdev_attribute *mce_attributes[] = {
- &attr_bank0ctl, &attr_bank1ctl, &attr_bank2ctl,
- &attr_bank3ctl, &attr_bank4ctl, &attr_bank5ctl,
&attr_tolerant.attr, &attr_check_interval, &attr_trigger,
NULL
};
if (err)
goto error;
}
+ for (i = 0; i < banks; i++) {
+ err = sysdev_create_file(&per_cpu(device_mce, cpu),
+ &bank_attrs[i]);
+ if (err)
+ goto error2;
+ }
cpu_set(cpu, mce_device_initialized);
return 0;
+error2:
+ while (--i >= 0) {
+ sysdev_remove_file(&per_cpu(device_mce, cpu),
+ &bank_attrs[i]);
+ }
error:
- while (i--) {
+ while (--i >= 0) {
sysdev_remove_file(&per_cpu(device_mce,cpu),
mce_attributes[i]);
}
for (i = 0; mce_attributes[i]; i++)
sysdev_remove_file(&per_cpu(device_mce,cpu),
mce_attributes[i]);
+ for (i = 0; i < banks; i++)
+ sysdev_remove_file(&per_cpu(device_mce, cpu),
+ &bank_attrs[i]);
sysdev_unregister(&per_cpu(device_mce,cpu));
cpu_clear(cpu, mce_device_initialized);
}
+/* Make sure there are no machine checks on offlined CPUs. */
+static void mce_disable_cpu(void *h)
+{
+ int i;
+
+ if (!mce_available(¤t_cpu_data))
+ return;
+ for (i = 0; i < banks; i++)
+ wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+}
+
+static void mce_reenable_cpu(void *h)
+{
+ int i;
+
+ if (!mce_available(¤t_cpu_data))
+ return;
+ for (i = 0; i < banks; i++)
+ wrmsrl(MSR_IA32_MC0_CTL + i*4, bank[i]);
+}
+
/* Get notified when a cpu comes on/off. Be hotplug friendly. */
static int __cpuinit 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) {
case CPU_ONLINE:
threshold_cpu_callback(action, cpu);
mce_remove_device(cpu);
break;
+ case CPU_DOWN_PREPARE:
+ case CPU_DOWN_PREPARE_FROZEN:
+ del_timer_sync(t);
+ smp_call_function_single(cpu, mce_disable_cpu, NULL, 1);
+ break;
+ case CPU_DOWN_FAILED:
+ case CPU_DOWN_FAILED_FROZEN:
+ t->expires = round_jiffies_relative(jiffies + next_interval);
+ add_timer_on(t, cpu);
+ smp_call_function_single(cpu, mce_reenable_cpu, NULL, 1);
+ break;
}
return NOTIFY_OK;
}
.notifier_call = mce_cpu_callback,
};
+static __init int mce_init_banks(void)
+{
+ int i;
+
+ bank_attrs = kzalloc(sizeof(struct sysdev_attribute) * banks,
+ GFP_KERNEL);
+ if (!bank_attrs)
+ return -ENOMEM;
+
+ for (i = 0; i < banks; i++) {
+ struct sysdev_attribute *a = &bank_attrs[i];
+ a->attr.name = kasprintf(GFP_KERNEL, "bank%d", i);
+ if (!a->attr.name)
+ goto nomem;
+ a->attr.mode = 0644;
+ a->show = show_bank;
+ a->store = set_bank;
+ }
+ return 0;
+
+nomem:
+ while (--i >= 0)
+ kfree(bank_attrs[i].attr.name);
+ kfree(bank_attrs);
+ bank_attrs = NULL;
+ return -ENOMEM;
+}
+
static __init int mce_init_device(void)
{
int err;
if (!mce_available(&boot_cpu_data))
return -EIO;
+
+ err = mce_init_banks();
+ if (err)
+ return err;
+
err = sysdev_class_register(&mce_sysclass);
if (err)
return err;
projects / linux-2.6-omap-h63xx.git / commitdiff