root/arch/x86/kernel/cpu/mcheck/non-fatal.c

DEFINITIONS

1. mce_checkregs
2. mce_work_fn
3. init_nonfatal_mce_checker

/*
 * Non Fatal Machine Check Exception Reporting
 *
 * (C) Copyright 2002 Dave Jones. <davej@codemonkey.org.uk>
 *
 * This file contains routines to check for non-fatal MCEs every 15s
 *
 */

#include <linux/init.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/workqueue.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/module.h>

#include <asm/processor.h>
#include <asm/system.h>
#include <asm/msr.h>

#include "mce.h"

static int firstbank;

#define MCE_RATE        15*HZ   /* timer rate is 15s */

static void mce_checkregs(void *info)
{
        u32 low, high;
        int i;

        for (i = firstbank; i < nr_mce_banks; i++) {
                rdmsr(MSR_IA32_MC0_STATUS+i*4, low, high);

                if (high & (1<<31)) {
                        printk(KERN_INFO "MCE: The hardware reports a non "
                                "fatal, correctable incident occurred on "
                                "CPU %d.\n",
                                smp_processor_id());
                        printk(KERN_INFO "Bank %d: %08x%08x\n", i, high, low);

                        /*
                         * Scrub the error so we don't pick it up in MCE_RATE
                         * seconds time.
                         */
                        wrmsr(MSR_IA32_MC0_STATUS+i*4, 0UL, 0UL);

                        /* Serialize */
                        wmb();
                        add_taint(TAINT_MACHINE_CHECK);
                }
        }
}

static void mce_work_fn(struct work_struct *work);
static DECLARE_DELAYED_WORK(mce_work, mce_work_fn);

static void mce_work_fn(struct work_struct *work)
{
        on_each_cpu(mce_checkregs, NULL, 1);
        schedule_delayed_work(&mce_work, round_jiffies_relative(MCE_RATE));
}

static int __init init_nonfatal_mce_checker(void)
{
        struct cpuinfo_x86 *c = &boot_cpu_data;

        /* Check for MCE support */
        if (!cpu_has(c, X86_FEATURE_MCE))
                return -ENODEV;

        /* Check for PPro style MCA */
        if (!cpu_has(c, X86_FEATURE_MCA))
                return -ENODEV;

        /* Some Athlons misbehave when we frob bank 0 */
        if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
                boot_cpu_data.x86 == 6)
                        firstbank = 1;
        else
                        firstbank = 0;

        /*
         * Check for non-fatal errors every MCE_RATE s
         */
        schedule_delayed_work(&mce_work, round_jiffies_relative(MCE_RATE));
        printk(KERN_INFO "Machine check exception polling timer started.\n");
        return 0;
}
module_init(init_nonfatal_mce_checker);

MODULE_LICENSE("GPL");