diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mcheck/mce_64.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce_64.c | 1187 |
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 6fb0b359d2a5..000000000000 --- 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, ¬ify_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(¤t_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, ¬ify_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(¤t_cpu_data); - 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) -{ - 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(¤t_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(¤t_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); |