x86, mce: unify

move mce_64.c => mce.c and glue it up in the Makefile.
Remove mce_32.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 0 insertions, 1311 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 2e2c3d2..0000000
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ /dev/null
@@ -1,1311 +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/thread_info.h>
-#include <linux/capability.h>
-#include <linux/miscdevice.h>
-#include <linux/ratelimit.h>
-#include <linux/kallsyms.h>
-#include <linux/rcupdate.h>
-#include <linux/smp_lock.h>
-#include <linux/kobject.h>
-#include <linux/kdebug.h>
-#include <linux/kernel.h>
-#include <linux/percpu.h>
-#include <linux/string.h>
-#include <linux/sysdev.h>
-#include <linux/ctype.h>
-#include <linux/sched.h>
-#include <linux/sysfs.h>
-#include <linux/types.h>
-#include <linux/init.h>
-#include <linux/kmod.h>
-#include <linux/poll.h>
-#include <linux/cpu.h>
-#include <linux/fs.h>
-
-#include <asm/processor.h>
-#include <asm/uaccess.h>
-#include <asm/idle.h>
-#include <asm/mce.h>
-#include <asm/msr.h>
-#include <asm/smp.h>
-
-#include "mce.h"
-
-#ifdef CONFIG_X86_64
-
-#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 ones:
-			 */
-			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;
-	int panicm_found = 0;
-	u64 mcestart = 0;
-	int i;
-	/*
-	 * 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 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 *unused)
-{
-	/* 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)
-{
-	unsigned b;
-	u64 cap;
-
-	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)
-{
-	mce_banks_t all_banks;
-	u64 cap;
-	int i;
-
-	/*
-	 * 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 DEFINE_MUTEX(mce_read_mutex);
-
-static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize,
-			loff_t *off)
-{
-	char __user *buf = ubuf;
-	unsigned long *cpu_tsc;
-	unsigned prev, next;
-	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;
-}
-__setup("nomce", mcheck_disable);
-
-/*
- * 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(KERN_INFO "mce= argument %s ignored. Please use /sys\n",
-		       str);
-		return 0;
-	}
-	return 1;
-}
-__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 re-added 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);
-
-__cpuinitdata
-void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
-
-/* 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 ctrl 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)
-{
-	unsigned long action = *(unsigned long *)h;
-	int i;
-
-	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);
-
-#else /* CONFIG_X86_32: */
-
-int mce_disabled;
-
-int nr_mce_banks;
-EXPORT_SYMBOL_GPL(nr_mce_banks);	/* non-fatal.o */
-
-/* Handle unconfigured int18 (should never happen) */
-static void unexpected_machine_check(struct pt_regs *regs, long error_code)
-{
-	printk(KERN_ERR "CPU#%d: Unexpected int18 (Machine Check).\n",
-	       smp_processor_id());
-}
-
-/* Call the installed machine check handler for this CPU setup. */
-void (*machine_check_vector)(struct pt_regs *, long error_code) =
-						unexpected_machine_check;
-
-/* This has to be run for each processor */
-void mcheck_init(struct cpuinfo_x86 *c)
-{
-	if (mce_disabled == 1)
-		return;
-
-	switch (c->x86_vendor) {
-	case X86_VENDOR_AMD:
-		amd_mcheck_init(c);
-		break;
-
-	case X86_VENDOR_INTEL:
-		if (c->x86 == 5)
-			intel_p5_mcheck_init(c);
-		if (c->x86 == 6)
-			intel_p6_mcheck_init(c);
-		if (c->x86 == 15)
-			intel_p4_mcheck_init(c);
-		break;
-
-	case X86_VENDOR_CENTAUR:
-		if (c->x86 == 5)
-			winchip_mcheck_init(c);
-		break;
-
-	default:
-		break;
-	}
-}
-
-static int __init mcheck_disable(char *str)
-{
-	mce_disabled = 1;
-	return 1;
-}
-
-static int __init mcheck_enable(char *str)
-{
-	mce_disabled = -1;
-	return 1;
-}
-
-__setup("nomce", mcheck_disable);
-__setup("mce", mcheck_enable);
-
-#endif /* CONFIG_X86_32 */