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Diffstat (limited to 'arch/x86/kernel/cpu/mcheck/mce_64.c')
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce_64.c1187
1 files changed, 0 insertions, 1187 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c
deleted file mode 100644
index 6fb0b359d2a..00000000000
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ /dev/null
@@ -1,1187 +0,0 @@
-/*
- * Machine check handler.
- * 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/types.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/smp_lock.h>
-#include <linux/string.h>
-#include <linux/rcupdate.h>
-#include <linux/kallsyms.h>
-#include <linux/sysdev.h>
-#include <linux/miscdevice.h>
-#include <linux/fs.h>
-#include <linux/capability.h>
-#include <linux/cpu.h>
-#include <linux/percpu.h>
-#include <linux/poll.h>
-#include <linux/thread_info.h>
-#include <linux/ctype.h>
-#include <linux/kmod.h>
-#include <linux/kdebug.h>
-#include <linux/kobject.h>
-#include <linux/sysfs.h>
-#include <linux/ratelimit.h>
-#include <asm/processor.h>
-#include <asm/msr.h>
-#include <asm/mce.h>
-#include <asm/uaccess.h>
-#include <asm/smp.h>
-#include <asm/idle.h>
-
-#define MISC_MCELOG_MINOR 227
-
-atomic_t mce_entry;
-
-static int mce_dont_init;
-
-/*
- * Tolerant levels:
- * 0: always panic on uncorrected errors, log corrected errors
- * 1: panic or SIGBUS on uncorrected errors, log corrected errors
- * 2: SIGBUS or log uncorrected errors (if possible), log corrected errors
- * 3: never panic or SIGBUS, log all errors (for testing only)
- */
-static int tolerant = 1;
-static int banks;
-static u64 *bank;
-static unsigned long notify_user;
-static int rip_msr;
-static int mce_bootlog = -1;
-static atomic_t mce_events;
-
-static char trigger[128];
-static char *trigger_argv[2] = { trigger, NULL };
-
-static DECLARE_WAIT_QUEUE_HEAD(mce_wait);
-
-/* MCA banks polled by the period polling timer for corrected events */
-DEFINE_PER_CPU(mce_banks_t, mce_poll_banks) = {
- [0 ... BITS_TO_LONGS(MAX_NR_BANKS)-1] = ~0UL
-};
-
-/* 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
- * separate MCEs from kernel messages to avoid bogus bug reports.
- */
-
-static struct mce_log mcelog = {
- MCE_LOG_SIGNATURE,
- MCE_LOG_LEN,
-};
-
-void mce_log(struct mce *mce)
-{
- unsigned next, entry;
- atomic_inc(&mce_events);
- mce->finished = 0;
- wmb();
- for (;;) {
- entry = rcu_dereference(mcelog.next);
- for (;;) {
- /* When the buffer fills up discard new entries. Assume
- that the earlier errors are the more interesting. */
- if (entry >= MCE_LOG_LEN) {
- set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog.flags);
- return;
- }
- /* Old left over entry. Skip. */
- if (mcelog.entry[entry].finished) {
- entry++;
- continue;
- }
- break;
- }
- smp_rmb();
- next = entry + 1;
- if (cmpxchg(&mcelog.next, entry, next) == entry)
- break;
- }
- memcpy(mcelog.entry + entry, mce, sizeof(struct mce));
- wmb();
- mcelog.entry[entry].finished = 1;
- wmb();
-
- set_bit(0, &notify_user);
-}
-
-static void print_mce(struct mce *m)
-{
- printk(KERN_EMERG "\n"
- KERN_EMERG "HARDWARE ERROR\n"
- KERN_EMERG
- "CPU %d: Machine Check Exception: %16Lx Bank %d: %016Lx\n",
- m->cpu, m->mcgstatus, m->bank, m->status);
- if (m->ip) {
- printk(KERN_EMERG "RIP%s %02x:<%016Lx> ",
- !(m->mcgstatus & MCG_STATUS_EIPV) ? " !INEXACT!" : "",
- m->cs, m->ip);
- if (m->cs == __KERNEL_CS)
- print_symbol("{%s}", m->ip);
- printk("\n");
- }
- printk(KERN_EMERG "TSC %llx ", m->tsc);
- if (m->addr)
- printk("ADDR %llx ", m->addr);
- if (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 "
- "and contact your hardware vendor\n");
-}
-
-static void mce_panic(char *msg, struct mce *backup, unsigned long start)
-{
- int i;
-
- oops_begin();
- for (i = 0; i < MCE_LOG_LEN; i++) {
- unsigned long tsc = mcelog.entry[i].tsc;
-
- if (time_before(tsc, start))
- continue;
- print_mce(&mcelog.entry[i]);
- if (backup && mcelog.entry[i].tsc == backup->tsc)
- backup = NULL;
- }
- if (backup)
- print_mce(backup);
- panic(msg);
-}
-
-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);
-}
-
-static inline void mce_get_rip(struct mce *m, struct pt_regs *regs)
-{
- if (regs && (m->mcgstatus & MCG_STATUS_RIPV)) {
- m->ip = regs->ip;
- m->cs = regs->cs;
- } else {
- m->ip = 0;
- m->cs = 0;
- }
- if (rip_msr) {
- /* Assume the RIP in the MSR is exact. Is this true? */
- m->mcgstatus |= MCG_STATUS_EIPV;
- rdmsrl(rip_msr, m->ip);
- m->cs = 0;
- }
-}
-
-/*
- * 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, mce_banks_t *b)
-{
- struct mce m;
- int i;
-
- mce_setup(&m);
-
- rdmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus);
- for (i = 0; i < banks; i++) {
- if (!bank[i] || !test_bit(i, *b))
- 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.
- */
- if (!(flags & MCP_DONTLOG)) {
- 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)
-{
- struct mce m, panicm;
- u64 mcestart = 0;
- int i;
- int panicm_found = 0;
- /*
- * If no_way_out gets set, there is no safe way to recover from this
- * MCE. If tolerant is cranked up, we'll try anyway.
- */
- int no_way_out = 0;
- /*
- * If kill_it gets set, there might be a way to recover from this
- * error.
- */
- int kill_it = 0;
- DECLARE_BITMAP(toclear, MAX_NR_BANKS);
-
- atomic_inc(&mce_entry);
-
- if (notify_die(DIE_NMI, "machine check", regs, error_code,
- 18, SIGKILL) == NOTIFY_STOP)
- goto out2;
- if (!banks)
- goto out2;
-
- mce_setup(&m);
-
- rdmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus);
- /* if the restart IP is not valid, we're done for */
- if (!(m.mcgstatus & MCG_STATUS_RIPV))
- no_way_out = 1;
-
- rdtscll(mcestart);
- barrier();
-
- for (i = 0; i < banks; i++) {
- __clear_bit(i, toclear);
- if (!bank[i])
- continue;
-
- m.misc = 0;
- m.addr = 0;
- m.bank = i;
-
- 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);
- /*
- * If this error was uncorrectable and there was
- * an overflow, we're in trouble. If no overflow,
- * we might get away with just killing a task.
- */
- if (m.status & MCI_STATUS_UC) {
- if (tolerant < 1 || m.status & MCI_STATUS_OVER)
- 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_MISC + i*4, m.misc);
- if (m.status & MCI_STATUS_ADDRV)
- rdmsrl(MSR_IA32_MC0_ADDR + i*4, m.addr);
-
- mce_get_rip(&m, regs);
- mce_log(&m);
-
- /* Did this bank cause the exception? */
- /* Assume that the bank with uncorrectable errors did it,
- and that there is only a single one. */
- if ((m.status & MCI_STATUS_UC) && (m.status & MCI_STATUS_EN)) {
- panicm = m;
- panicm_found = 1;
- }
- }
-
- /* If we didn't find an uncorrectable error, pick
- the last one (shouldn't happen, just being safe). */
- if (!panicm_found)
- panicm = m;
-
- /*
- * If we have decided that we just CAN'T continue, and the user
- * has not set tolerant to an insane level, give up and die.
- */
- if (no_way_out && tolerant < 3)
- mce_panic("Machine check", &panicm, mcestart);
-
- /*
- * If the error seems to be unrecoverable, something should be
- * done. Try to kill as little as possible. If we can kill just
- * one task, do that. If the user has set the tolerance very
- * high, don't try to do anything at all.
- */
- if (kill_it && tolerant < 3) {
- int user_space = 0;
-
- /*
- * If the EIPV bit is set, it means the saved IP is the
- * instruction which caused the MCE.
- */
- if (m.mcgstatus & MCG_STATUS_EIPV)
- user_space = panicm.ip && (panicm.cs & 3);
-
- /*
- * If we know that the error was in user space, send a
- * SIGBUS. Otherwise, panic if tolerance is low.
- *
- * force_sig() takes an awful lot of locks and has a slight
- * risk of deadlocking.
- */
- if (user_space) {
- force_sig(SIGBUS, current);
- } else if (panic_on_oops || tolerant < 2) {
- mce_panic("Uncorrected machine check",
- &panicm, mcestart);
- }
- }
-
- /* notify userspace ASAP */
- set_thread_flag(TIF_MCE_NOTIFY);
-
- /* the last thing we do is clear state */
- 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);
-}
-
-#ifdef CONFIG_X86_MCE_INTEL
-/***
- * mce_log_therm_throt_event - Logs the thermal throttling event to mcelog
- * @cpu: The CPU on which the event occurred.
- * @status: Event status information
- *
- * This function should be called by the thermal interrupt after the
- * event has been processed and the decision was made to log the event
- * further.
- *
- * The status parameter will be saved to the 'status' field of 'struct mce'
- * and historically has been the register value of the
- * MSR_IA32_THERMAL_STATUS (Intel) msr.
- */
-void mce_log_therm_throt_event(__u64 status)
-{
- struct mce m;
-
- mce_setup(&m);
- m.bank = MCE_THERMAL_BANK;
- m.status = status;
- mce_log(&m);
-}
-#endif /* CONFIG_X86_MCE_INTEL */
-
-/*
- * Periodic polling timer for "silent" machine check errors. If the
- * poller finds an MCE, poll 2x faster. When the poller finds no more
- * errors, poll 2x slower (up to check_interval seconds).
- */
-
-static int check_interval = 5 * 60; /* 5 minutes */
-static DEFINE_PER_CPU(int, next_interval); /* in jiffies */
-static void mcheck_timer(unsigned long);
-static DEFINE_PER_CPU(struct timer_list, mce_timer);
-
-static void mcheck_timer(unsigned long data)
-{
- struct timer_list *t = &per_cpu(mce_timer, data);
- int *n;
-
- WARN_ON(smp_processor_id() != data);
-
- if (mce_available(&current_cpu_data))
- machine_check_poll(MCP_TIMESTAMP,
- &__get_cpu_var(mce_poll_banks));
-
- /*
- * Alert userspace if needed. If we logged an MCE, reduce the
- * polling interval, otherwise increase the polling interval.
- */
- n = &__get_cpu_var(next_interval);
- if (mce_notify_user()) {
- *n = max(*n/2, HZ/100);
- } else {
- *n = min(*n*2, (int)round_jiffies_relative(check_interval*HZ));
- }
-
- t->expires = jiffies + *n;
- 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);
-
-/*
- * 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)
-{
- /* Not more than two messages every minute */
- static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2);
-
- clear_thread_flag(TIF_MCE_NOTIFY);
- if (test_and_clear_bit(0, &notify_user)) {
- wake_up_interruptible(&mce_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 (__ratelimit(&ratelimit))
- printk(KERN_INFO "Machine check events logged\n");
-
- return 1;
- }
- return 0;
-}
-
-/* see if the idle task needs to notify userspace */
-static int
-mce_idle_callback(struct notifier_block *nfb, unsigned long action, void *junk)
-{
- /* IDLE_END should be safe - interrupts are back on */
- if (action == IDLE_END && test_thread_flag(TIF_MCE_NOTIFY))
- mce_notify_user();
-
- return NOTIFY_OK;
-}
-
-static struct notifier_block mce_idle_notifier = {
- .notifier_call = mce_idle_callback,
-};
-
-static __init int periodic_mcheck_init(void)
-{
- idle_notifier_register(&mce_idle_notifier);
- return 0;
-}
-__initcall(periodic_mcheck_init);
-
-/*
- * Initialize Machine Checks for a CPU.
- */
-static int mce_cap_init(void)
-{
- u64 cap;
- unsigned b;
-
- rdmsrl(MSR_IA32_MCG_CAP, cap);
- 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;
-
- return 0;
-}
-
-static void mce_init(void *dummy)
-{
- u64 cap;
- int i;
- mce_banks_t all_banks;
-
- /*
- * Log the machine checks left over from the previous reset.
- */
- bitmap_fill(all_banks, MAX_NR_BANKS);
- machine_check_poll(MCP_UC|(!mce_bootlog ? MCP_DONTLOG : 0), &all_banks);
-
- 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++) {
- 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 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 && banks > 4)
- /* disable GART TBL walk error reporting, which trips off
- incorrectly with the IOMMU & 3ware & Cerberus. */
- 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. */
- mce_bootlog = 0;
- }
-
-}
-
-static void mce_cpu_features(struct cpuinfo_x86 *c)
-{
- switch (c->x86_vendor) {
- case X86_VENDOR_INTEL:
- mce_intel_feature_init(c);
- break;
- case X86_VENDOR_AMD:
- mce_amd_feature_init(c);
- break;
- default:
- break;
- }
-}
-
-static void mce_init_timer(void)
-{
- struct timer_list *t = &__get_cpu_var(mce_timer);
- int *n = &__get_cpu_var(next_interval);
-
- *n = check_interval * HZ;
- if (!*n)
- return;
- setup_timer(t, mcheck_timer, smp_processor_id());
- t->expires = round_jiffies(jiffies + *n);
- 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)
-{
- if (!mce_available(c))
- return;
-
- if (mce_cap_init() < 0) {
- mce_dont_init = 1;
- return;
- }
- mce_cpu_quirks(c);
-
- mce_init(NULL);
- mce_cpu_features(c);
- mce_init_timer();
-}
-
-/*
- * Character device to read and clear the MCE log.
- */
-
-static DEFINE_SPINLOCK(mce_state_lock);
-static int open_count; /* #times opened */
-static int open_exclu; /* already open exclusive? */
-
-static int mce_open(struct inode *inode, struct file *file)
-{
- lock_kernel();
- spin_lock(&mce_state_lock);
-
- if (open_exclu || (open_count && (file->f_flags & O_EXCL))) {
- spin_unlock(&mce_state_lock);
- unlock_kernel();
- return -EBUSY;
- }
-
- if (file->f_flags & O_EXCL)
- open_exclu = 1;
- open_count++;
-
- spin_unlock(&mce_state_lock);
- unlock_kernel();
-
- return nonseekable_open(inode, file);
-}
-
-static int mce_release(struct inode *inode, struct file *file)
-{
- spin_lock(&mce_state_lock);
-
- open_count--;
- open_exclu = 0;
-
- spin_unlock(&mce_state_lock);
-
- return 0;
-}
-
-static void collect_tscs(void *data)
-{
- unsigned long *cpu_tsc = (unsigned long *)data;
-
- rdtscll(cpu_tsc[smp_processor_id()]);
-}
-
-static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize,
- loff_t *off)
-{
- unsigned long *cpu_tsc;
- static DEFINE_MUTEX(mce_read_mutex);
- unsigned prev, next;
- char __user *buf = ubuf;
- int i, err;
-
- cpu_tsc = kmalloc(nr_cpu_ids * sizeof(long), GFP_KERNEL);
- if (!cpu_tsc)
- return -ENOMEM;
-
- mutex_lock(&mce_read_mutex);
- next = rcu_dereference(mcelog.next);
-
- /* Only supports full reads right now */
- if (*off != 0 || usize < MCE_LOG_LEN*sizeof(struct mce)) {
- mutex_unlock(&mce_read_mutex);
- kfree(cpu_tsc);
- return -EINVAL;
- }
-
- err = 0;
- 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();
- }
- smp_rmb();
- err |= copy_to_user(buf, mcelog.entry + i,
- sizeof(struct mce));
- buf += sizeof(struct mce);
-timeout:
- ;
- }
-
- memset(mcelog.entry + prev, 0,
- (next - prev) * sizeof(struct mce));
- prev = next;
- next = cmpxchg(&mcelog.next, prev, 0);
- } while (next != prev);
-
- synchronize_sched();
-
- /*
- * Collect entries that were still getting written before the
- * synchronize.
- */
- on_each_cpu(collect_tscs, cpu_tsc, 1);
- for (i = next; i < MCE_LOG_LEN; i++) {
- if (mcelog.entry[i].finished &&
- mcelog.entry[i].tsc < cpu_tsc[mcelog.entry[i].cpu]) {
- err |= copy_to_user(buf, mcelog.entry+i,
- sizeof(struct mce));
- smp_rmb();
- buf += sizeof(struct mce);
- memset(&mcelog.entry[i], 0, sizeof(struct mce));
- }
- }
- mutex_unlock(&mce_read_mutex);
- kfree(cpu_tsc);
- return err ? -EFAULT : buf - ubuf;
-}
-
-static unsigned int mce_poll(struct file *file, poll_table *wait)
-{
- poll_wait(file, &mce_wait, wait);
- if (rcu_dereference(mcelog.next))
- return POLLIN | POLLRDNORM;
- return 0;
-}
-
-static long mce_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
-{
- int __user *p = (int __user *)arg;
-
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
- switch (cmd) {
- case MCE_GET_RECORD_LEN:
- return put_user(sizeof(struct mce), p);
- case MCE_GET_LOG_LEN:
- return put_user(MCE_LOG_LEN, p);
- case MCE_GETCLEAR_FLAGS: {
- unsigned flags;
-
- do {
- flags = mcelog.flags;
- } while (cmpxchg(&mcelog.flags, flags, 0) != flags);
- return put_user(flags, p);
- }
- default:
- return -ENOTTY;
- }
-}
-
-static const struct file_operations mce_chrdev_ops = {
- .open = mce_open,
- .release = mce_release,
- .read = mce_read,
- .poll = mce_poll,
- .unlocked_ioctl = mce_ioctl,
-};
-
-static struct miscdevice mce_log_device = {
- MISC_MCELOG_MINOR,
- "mcelog",
- &mce_chrdev_ops,
-};
-
-/*
- * Old style boot options parsing. Only for compatibility.
- */
-static int __init mcheck_disable(char *str)
-{
- mce_dont_init = 1;
- return 1;
-}
-
-/* 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. */
-static int __init mcheck_enable(char *str)
-{
- if (!strcmp(str, "off"))
- mce_dont_init = 1;
- else if (!strcmp(str, "bootlog") || !strcmp(str,"nobootlog"))
- mce_bootlog = str[0] == 'b';
- else if (isdigit(str[0]))
- get_option(&str, &tolerant);
- else
- printk("mce= argument %s ignored. Please use /sys", str);
- return 1;
-}
-
-__setup("nomce", mcheck_disable);
-__setup("mce=", mcheck_enable);
-
-/*
- * 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. */
-static int mce_resume(struct sys_device *dev)
-{
- mce_init(NULL);
- mce_cpu_features(&current_cpu_data);
- return 0;
-}
-
-static void mce_cpu_restart(void *data)
-{
- del_timer_sync(&__get_cpu_var(mce_timer));
- if (mce_available(&current_cpu_data))
- mce_init(NULL);
- mce_init_timer();
-}
-
-/* Reinit MCEs after user configuration changes */
-static void mce_restart(void)
-{
- 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",
-};
-
-DEFINE_PER_CPU(struct sys_device, device_mce);
-void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu) __cpuinitdata;
-
-/* Why are there no generic functions for this? */
-#define ACCESSOR(name, var, start) \
- static ssize_t show_ ## name(struct sys_device *s, \
- struct sysdev_attribute *attr, \
- char *buf) { \
- return sprintf(buf, "%lx\n", (unsigned long)var); \
- } \
- static ssize_t set_ ## name(struct sys_device *s, \
- struct sysdev_attribute *attr, \
- const char *buf, size_t siz) { \
- char *end; \
- unsigned long new = simple_strtoul(buf, &end, 0); \
- if (end == buf) return -EINVAL; \
- var = new; \
- start; \
- return end-buf; \
- } \
- static SYSDEV_ATTR(name, 0644, show_ ## name, set_ ## name);
-
-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)
-{
- strcpy(buf, trigger);
- strcat(buf, "\n");
- return strlen(trigger) + 1;
-}
-
-static ssize_t set_trigger(struct sys_device *s, struct sysdev_attribute *attr,
- const char *buf,size_t siz)
-{
- char *p;
- int len;
- strncpy(trigger, buf, sizeof(trigger));
- trigger[sizeof(trigger)-1] = 0;
- len = strlen(trigger);
- p = strchr(trigger, '\n');
- if (*p) *p = 0;
- return len;
-}
-
-static SYSDEV_ATTR(trigger, 0644, show_trigger, set_trigger);
-static SYSDEV_INT_ATTR(tolerant, 0644, tolerant);
-ACCESSOR(check_interval,check_interval,mce_restart())
-static struct sysdev_attribute *mce_attributes[] = {
- &attr_tolerant.attr, &attr_check_interval, &attr_trigger,
- NULL
-};
-
-static cpumask_var_t mce_device_initialized;
-
-/* Per cpu sysdev init. All of the cpus still share the same ctl bank */
-static __cpuinit int mce_create_device(unsigned int cpu)
-{
- int err;
- int i;
-
- if (!mce_available(&boot_cpu_data))
- return -EIO;
-
- memset(&per_cpu(device_mce, cpu).kobj, 0, sizeof(struct kobject));
- per_cpu(device_mce,cpu).id = cpu;
- per_cpu(device_mce,cpu).cls = &mce_sysclass;
-
- err = sysdev_register(&per_cpu(device_mce,cpu));
- if (err)
- return err;
-
- for (i = 0; mce_attributes[i]; i++) {
- err = sysdev_create_file(&per_cpu(device_mce,cpu),
- mce_attributes[i]);
- 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;
- }
- cpumask_set_cpu(cpu, mce_device_initialized);
-
- return 0;
-error2:
- while (--i >= 0) {
- sysdev_remove_file(&per_cpu(device_mce, cpu),
- &bank_attrs[i]);
- }
-error:
- while (--i >= 0) {
- sysdev_remove_file(&per_cpu(device_mce,cpu),
- mce_attributes[i]);
- }
- sysdev_unregister(&per_cpu(device_mce,cpu));
-
- return err;
-}
-
-static __cpuinit void mce_remove_device(unsigned int cpu)
-{
- int i;
-
- if (!cpumask_test_cpu(cpu, mce_device_initialized))
- return;
-
- 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));
- cpumask_clear_cpu(cpu, mce_device_initialized);
-}
-
-/* Make sure there are no machine checks on offlined CPUs. */
-static void mce_disable_cpu(void *h)
-{
- int i;
- unsigned long action = *(unsigned long *)h;
-
- if (!mce_available(&current_cpu_data))
- return;
- if (!(action & CPU_TASKS_FROZEN))
- cmci_clear();
- for (i = 0; i < banks; i++)
- wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
-}
-
-static void mce_reenable_cpu(void *h)
-{
- int i;
- unsigned long action = *(unsigned long *)h;
-
- if (!mce_available(&current_cpu_data))
- return;
- if (!(action & CPU_TASKS_FROZEN))
- cmci_reenable();
- 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:
- case CPU_ONLINE_FROZEN:
- mce_create_device(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_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, &action, 1);
- break;
- case CPU_DOWN_FAILED:
- case CPU_DOWN_FAILED_FROZEN:
- t->expires = round_jiffies(jiffies +
- __get_cpu_var(next_interval));
- add_timer_on(t, cpu);
- smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
- break;
- case CPU_POST_DEAD:
- /* intentionally ignoring frozen here */
- cmci_rediscover(cpu);
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block mce_cpu_notifier __cpuinitdata = {
- .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;
- int i = 0;
-
- if (!mce_available(&boot_cpu_data))
- return -EIO;
-
- alloc_cpumask_var(&mce_device_initialized, GFP_KERNEL);
-
- err = mce_init_banks();
- if (err)
- return err;
-
- err = sysdev_class_register(&mce_sysclass);
- if (err)
- return err;
-
- for_each_online_cpu(i) {
- err = mce_create_device(i);
- if (err)
- return err;
- }
-
- register_hotcpu_notifier(&mce_cpu_notifier);
- misc_register(&mce_log_device);
- return err;
-}
-
-device_initcall(mce_init_device);