4a0b2b4dbe
This allow to dynamically generate attributes and share show/store functions between attributes. Right now most attributes are generated by special macros and lots of duplicated code. With the attribute passed it's instead possible to attach some data to the attribute and then use that in shared low level functions to do different things. I need this for the dynamically generated bank attributes in the x86 machine check code, but it'll allow some further cleanups. I converted all users in tree to the new show/store prototype. It's a single huge patch to avoid unbisectable sections. Runtime tested: x86-32, x86-64 Compiled only: ia64, powerpc Not compile tested/only grep converted: sh, arm, avr32 Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
921 lines
22 KiB
C
921 lines
22 KiB
C
/*
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* Machine check handler.
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* K8 parts Copyright 2002,2003 Andi Kleen, SuSE Labs.
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* Rest from unknown author(s).
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* 2004 Andi Kleen. Rewrote most of it.
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*/
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#include <linux/init.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/smp_lock.h>
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#include <linux/string.h>
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#include <linux/rcupdate.h>
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#include <linux/kallsyms.h>
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#include <linux/sysdev.h>
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#include <linux/miscdevice.h>
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#include <linux/fs.h>
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#include <linux/capability.h>
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#include <linux/cpu.h>
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#include <linux/percpu.h>
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#include <linux/poll.h>
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#include <linux/thread_info.h>
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#include <linux/ctype.h>
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#include <linux/kmod.h>
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#include <linux/kdebug.h>
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#include <asm/processor.h>
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#include <asm/msr.h>
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#include <asm/mce.h>
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#include <asm/uaccess.h>
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#include <asm/smp.h>
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#include <asm/idle.h>
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#define MISC_MCELOG_MINOR 227
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#define NR_SYSFS_BANKS 6
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atomic_t mce_entry;
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static int mce_dont_init;
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/*
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* Tolerant levels:
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* 0: always panic on uncorrected errors, log corrected errors
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* 1: panic or SIGBUS on uncorrected errors, log corrected errors
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* 2: SIGBUS or log uncorrected errors (if possible), log corrected errors
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* 3: never panic or SIGBUS, log all errors (for testing only)
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*/
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static int tolerant = 1;
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static int banks;
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static unsigned long bank[NR_SYSFS_BANKS] = { [0 ... NR_SYSFS_BANKS-1] = ~0UL };
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static unsigned long notify_user;
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static int rip_msr;
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static int mce_bootlog = -1;
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static atomic_t mce_events;
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static char trigger[128];
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static char *trigger_argv[2] = { trigger, NULL };
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static DECLARE_WAIT_QUEUE_HEAD(mce_wait);
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/*
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* Lockless MCE logging infrastructure.
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* This avoids deadlocks on printk locks without having to break locks. Also
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* separate MCEs from kernel messages to avoid bogus bug reports.
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*/
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static struct mce_log mcelog = {
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MCE_LOG_SIGNATURE,
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MCE_LOG_LEN,
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};
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void mce_log(struct mce *mce)
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{
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unsigned next, entry;
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atomic_inc(&mce_events);
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mce->finished = 0;
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wmb();
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for (;;) {
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entry = rcu_dereference(mcelog.next);
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for (;;) {
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/* When the buffer fills up discard new entries. Assume
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that the earlier errors are the more interesting. */
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if (entry >= MCE_LOG_LEN) {
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set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog.flags);
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return;
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}
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/* Old left over entry. Skip. */
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if (mcelog.entry[entry].finished) {
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entry++;
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continue;
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}
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break;
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}
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smp_rmb();
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next = entry + 1;
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if (cmpxchg(&mcelog.next, entry, next) == entry)
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break;
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}
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memcpy(mcelog.entry + entry, mce, sizeof(struct mce));
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wmb();
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mcelog.entry[entry].finished = 1;
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wmb();
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set_bit(0, ¬ify_user);
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}
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static void print_mce(struct mce *m)
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{
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printk(KERN_EMERG "\n"
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KERN_EMERG "HARDWARE ERROR\n"
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KERN_EMERG
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"CPU %d: Machine Check Exception: %16Lx Bank %d: %016Lx\n",
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m->cpu, m->mcgstatus, m->bank, m->status);
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if (m->ip) {
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printk(KERN_EMERG "RIP%s %02x:<%016Lx> ",
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!(m->mcgstatus & MCG_STATUS_EIPV) ? " !INEXACT!" : "",
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m->cs, m->ip);
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if (m->cs == __KERNEL_CS)
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print_symbol("{%s}", m->ip);
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printk("\n");
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}
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printk(KERN_EMERG "TSC %Lx ", m->tsc);
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if (m->addr)
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printk("ADDR %Lx ", m->addr);
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if (m->misc)
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printk("MISC %Lx ", m->misc);
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printk("\n");
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printk(KERN_EMERG "This is not a software problem!\n");
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printk(KERN_EMERG "Run through mcelog --ascii to decode "
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"and contact your hardware vendor\n");
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}
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static void mce_panic(char *msg, struct mce *backup, unsigned long start)
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{
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int i;
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oops_begin();
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for (i = 0; i < MCE_LOG_LEN; i++) {
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unsigned long tsc = mcelog.entry[i].tsc;
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if (time_before(tsc, start))
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continue;
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print_mce(&mcelog.entry[i]);
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if (backup && mcelog.entry[i].tsc == backup->tsc)
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backup = NULL;
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}
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if (backup)
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print_mce(backup);
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panic(msg);
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}
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static int mce_available(struct cpuinfo_x86 *c)
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{
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return cpu_has(c, X86_FEATURE_MCE) && cpu_has(c, X86_FEATURE_MCA);
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}
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static inline void mce_get_rip(struct mce *m, struct pt_regs *regs)
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{
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if (regs && (m->mcgstatus & MCG_STATUS_RIPV)) {
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m->ip = regs->ip;
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m->cs = regs->cs;
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} else {
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m->ip = 0;
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m->cs = 0;
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}
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if (rip_msr) {
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/* Assume the RIP in the MSR is exact. Is this true? */
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m->mcgstatus |= MCG_STATUS_EIPV;
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rdmsrl(rip_msr, m->ip);
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m->cs = 0;
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}
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}
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/*
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* The actual machine check handler
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*/
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void do_machine_check(struct pt_regs * regs, long error_code)
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{
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struct mce m, panicm;
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u64 mcestart = 0;
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int i;
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int panicm_found = 0;
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/*
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* If no_way_out gets set, there is no safe way to recover from this
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* MCE. If tolerant is cranked up, we'll try anyway.
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*/
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int no_way_out = 0;
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/*
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* If kill_it gets set, there might be a way to recover from this
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* error.
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*/
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int kill_it = 0;
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atomic_inc(&mce_entry);
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if ((regs
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&& notify_die(DIE_NMI, "machine check", regs, error_code,
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18, SIGKILL) == NOTIFY_STOP)
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|| !banks)
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goto out2;
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memset(&m, 0, sizeof(struct mce));
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m.cpu = smp_processor_id();
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rdmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus);
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/* if the restart IP is not valid, we're done for */
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if (!(m.mcgstatus & MCG_STATUS_RIPV))
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no_way_out = 1;
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rdtscll(mcestart);
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barrier();
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for (i = 0; i < banks; i++) {
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if (i < NR_SYSFS_BANKS && !bank[i])
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continue;
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m.misc = 0;
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m.addr = 0;
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m.bank = i;
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m.tsc = 0;
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rdmsrl(MSR_IA32_MC0_STATUS + i*4, m.status);
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if ((m.status & MCI_STATUS_VAL) == 0)
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continue;
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if (m.status & MCI_STATUS_EN) {
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/* if PCC was set, there's no way out */
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no_way_out |= !!(m.status & MCI_STATUS_PCC);
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/*
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* If this error was uncorrectable and there was
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* an overflow, we're in trouble. If no overflow,
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* we might get away with just killing a task.
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*/
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if (m.status & MCI_STATUS_UC) {
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if (tolerant < 1 || m.status & MCI_STATUS_OVER)
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no_way_out = 1;
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kill_it = 1;
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}
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}
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if (m.status & MCI_STATUS_MISCV)
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rdmsrl(MSR_IA32_MC0_MISC + i*4, m.misc);
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if (m.status & MCI_STATUS_ADDRV)
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rdmsrl(MSR_IA32_MC0_ADDR + i*4, m.addr);
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mce_get_rip(&m, regs);
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if (error_code >= 0)
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rdtscll(m.tsc);
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if (error_code != -2)
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mce_log(&m);
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/* Did this bank cause the exception? */
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/* Assume that the bank with uncorrectable errors did it,
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and that there is only a single one. */
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if ((m.status & MCI_STATUS_UC) && (m.status & MCI_STATUS_EN)) {
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panicm = m;
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panicm_found = 1;
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}
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add_taint(TAINT_MACHINE_CHECK);
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}
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/* Never do anything final in the polling timer */
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if (!regs)
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goto out;
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/* If we didn't find an uncorrectable error, pick
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the last one (shouldn't happen, just being safe). */
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if (!panicm_found)
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panicm = m;
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/*
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* If we have decided that we just CAN'T continue, and the user
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* has not set tolerant to an insane level, give up and die.
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*/
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if (no_way_out && tolerant < 3)
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mce_panic("Machine check", &panicm, mcestart);
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/*
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* If the error seems to be unrecoverable, something should be
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* done. Try to kill as little as possible. If we can kill just
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* one task, do that. If the user has set the tolerance very
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* high, don't try to do anything at all.
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*/
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if (kill_it && tolerant < 3) {
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int user_space = 0;
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/*
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* If the EIPV bit is set, it means the saved IP is the
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* instruction which caused the MCE.
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*/
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if (m.mcgstatus & MCG_STATUS_EIPV)
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user_space = panicm.ip && (panicm.cs & 3);
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/*
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* If we know that the error was in user space, send a
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* SIGBUS. Otherwise, panic if tolerance is low.
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*
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* do_exit() takes an awful lot of locks and has a slight
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* risk of deadlocking.
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*/
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if (user_space) {
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do_exit(SIGBUS);
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} else if (panic_on_oops || tolerant < 2) {
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mce_panic("Uncorrected machine check",
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&panicm, mcestart);
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}
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}
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/* notify userspace ASAP */
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set_thread_flag(TIF_MCE_NOTIFY);
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out:
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/* the last thing we do is clear state */
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for (i = 0; i < banks; i++)
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wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
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wrmsrl(MSR_IA32_MCG_STATUS, 0);
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out2:
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atomic_dec(&mce_entry);
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}
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#ifdef CONFIG_X86_MCE_INTEL
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/***
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* mce_log_therm_throt_event - Logs the thermal throttling event to mcelog
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* @cpu: The CPU on which the event occurred.
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* @status: Event status information
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*
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* This function should be called by the thermal interrupt after the
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* event has been processed and the decision was made to log the event
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* further.
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*
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* The status parameter will be saved to the 'status' field of 'struct mce'
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* and historically has been the register value of the
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* MSR_IA32_THERMAL_STATUS (Intel) msr.
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*/
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void mce_log_therm_throt_event(unsigned int cpu, __u64 status)
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{
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struct mce m;
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memset(&m, 0, sizeof(m));
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m.cpu = cpu;
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m.bank = MCE_THERMAL_BANK;
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m.status = status;
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rdtscll(m.tsc);
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mce_log(&m);
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}
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#endif /* CONFIG_X86_MCE_INTEL */
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/*
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* Periodic polling timer for "silent" machine check errors. If the
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* poller finds an MCE, poll 2x faster. When the poller finds no more
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* errors, poll 2x slower (up to check_interval seconds).
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*/
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static int check_interval = 5 * 60; /* 5 minutes */
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static int next_interval; /* in jiffies */
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static void mcheck_timer(struct work_struct *work);
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static DECLARE_DELAYED_WORK(mcheck_work, mcheck_timer);
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static void mcheck_check_cpu(void *info)
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{
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if (mce_available(¤t_cpu_data))
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do_machine_check(NULL, 0);
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}
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static void mcheck_timer(struct work_struct *work)
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{
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on_each_cpu(mcheck_check_cpu, NULL, 1);
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/*
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* Alert userspace if needed. If we logged an MCE, reduce the
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* polling interval, otherwise increase the polling interval.
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*/
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if (mce_notify_user()) {
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next_interval = max(next_interval/2, HZ/100);
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} else {
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next_interval = min(next_interval * 2,
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(int)round_jiffies_relative(check_interval*HZ));
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}
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schedule_delayed_work(&mcheck_work, next_interval);
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}
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/*
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* This is only called from process context. This is where we do
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* anything we need to alert userspace about new MCEs. This is called
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* directly from the poller and also from entry.S and idle, thanks to
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* TIF_MCE_NOTIFY.
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*/
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int mce_notify_user(void)
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{
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clear_thread_flag(TIF_MCE_NOTIFY);
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if (test_and_clear_bit(0, ¬ify_user)) {
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static unsigned long last_print;
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unsigned long now = jiffies;
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wake_up_interruptible(&mce_wait);
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if (trigger[0])
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call_usermodehelper(trigger, trigger_argv, NULL,
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UMH_NO_WAIT);
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if (time_after_eq(now, last_print + (check_interval*HZ))) {
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last_print = now;
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printk(KERN_INFO "Machine check events logged\n");
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}
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return 1;
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}
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return 0;
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}
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/* see if the idle task needs to notify userspace */
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static int
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mce_idle_callback(struct notifier_block *nfb, unsigned long action, void *junk)
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{
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/* IDLE_END should be safe - interrupts are back on */
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if (action == IDLE_END && test_thread_flag(TIF_MCE_NOTIFY))
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mce_notify_user();
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return NOTIFY_OK;
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}
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static struct notifier_block mce_idle_notifier = {
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.notifier_call = mce_idle_callback,
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};
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static __init int periodic_mcheck_init(void)
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{
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next_interval = check_interval * HZ;
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if (next_interval)
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schedule_delayed_work(&mcheck_work,
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round_jiffies_relative(next_interval));
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idle_notifier_register(&mce_idle_notifier);
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return 0;
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}
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__initcall(periodic_mcheck_init);
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/*
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* Initialize Machine Checks for a CPU.
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*/
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static void mce_init(void *dummy)
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{
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u64 cap;
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int i;
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rdmsrl(MSR_IA32_MCG_CAP, cap);
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banks = cap & 0xff;
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if (banks > MCE_EXTENDED_BANK) {
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banks = MCE_EXTENDED_BANK;
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printk(KERN_INFO "MCE: warning: using only %d banks\n",
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MCE_EXTENDED_BANK);
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}
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/* Use accurate RIP reporting if available. */
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if ((cap & (1<<9)) && ((cap >> 16) & 0xff) >= 9)
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rip_msr = MSR_IA32_MCG_EIP;
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/* Log the machine checks left over from the previous reset.
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This also clears all registers */
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do_machine_check(NULL, mce_bootlog ? -1 : -2);
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set_in_cr4(X86_CR4_MCE);
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if (cap & MCG_CTL_P)
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wrmsr(MSR_IA32_MCG_CTL, 0xffffffff, 0xffffffff);
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for (i = 0; i < banks; i++) {
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if (i < NR_SYSFS_BANKS)
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wrmsrl(MSR_IA32_MC0_CTL+4*i, bank[i]);
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else
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wrmsrl(MSR_IA32_MC0_CTL+4*i, ~0UL);
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wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
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}
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}
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/* Add per CPU specific workarounds here */
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static void __cpuinit mce_cpu_quirks(struct cpuinfo_x86 *c)
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{
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/* This should be disabled by the BIOS, but isn't always */
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if (c->x86_vendor == X86_VENDOR_AMD) {
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if(c->x86 == 15)
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/* disable GART TBL walk error reporting, which trips off
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incorrectly with the IOMMU & 3ware & Cerberus. */
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clear_bit(10, &bank[4]);
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if(c->x86 <= 17 && mce_bootlog < 0)
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/* Lots of broken BIOS around that don't clear them
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by default and leave crap in there. Don't log. */
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mce_bootlog = 0;
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}
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}
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static void __cpuinit mce_cpu_features(struct cpuinfo_x86 *c)
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{
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switch (c->x86_vendor) {
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case X86_VENDOR_INTEL:
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mce_intel_feature_init(c);
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break;
|
|
case X86_VENDOR_AMD:
|
|
mce_amd_feature_init(c);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Called for each booted CPU to set up machine checks.
|
|
* Must be called with preempt off.
|
|
*/
|
|
void __cpuinit mcheck_init(struct cpuinfo_x86 *c)
|
|
{
|
|
static cpumask_t mce_cpus = CPU_MASK_NONE;
|
|
|
|
mce_cpu_quirks(c);
|
|
|
|
if (mce_dont_init ||
|
|
cpu_test_and_set(smp_processor_id(), mce_cpus) ||
|
|
!mce_available(c))
|
|
return;
|
|
|
|
mce_init(NULL);
|
|
mce_cpu_features(c);
|
|
}
|
|
|
|
/*
|
|
* 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 next;
|
|
char __user *buf = ubuf;
|
|
int i, err;
|
|
|
|
cpu_tsc = kmalloc(NR_CPUS * 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;
|
|
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;
|
|
}
|
|
cpu_relax();
|
|
}
|
|
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;
|
|
|
|
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,
|
|
};
|
|
|
|
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.
|
|
*/
|
|
static int __init mcheck_disable(char *str)
|
|
{
|
|
mce_dont_init = 1;
|
|
return 1;
|
|
}
|
|
|
|
/* mce=off disables machine check. Note you can re-enable it later
|
|
using sysfs.
|
|
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
|
|
*/
|
|
|
|
/* 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);
|
|
return 0;
|
|
}
|
|
|
|
/* 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));
|
|
}
|
|
|
|
static struct sysdev_class mce_sysclass = {
|
|
.resume = mce_resume,
|
|
.name = "machinecheck",
|
|
};
|
|
|
|
DEFINE_PER_CPU(struct sys_device, device_mce);
|
|
|
|
/* 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);
|
|
|
|
/*
|
|
* 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 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);
|
|
ACCESSOR(tolerant,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_check_interval, &attr_trigger,
|
|
NULL
|
|
};
|
|
|
|
static cpumask_t mce_device_initialized = CPU_MASK_NONE;
|
|
|
|
/* 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;
|
|
}
|
|
cpu_set(cpu, mce_device_initialized);
|
|
|
|
return 0;
|
|
error:
|
|
while (i--) {
|
|
sysdev_remove_file(&per_cpu(device_mce,cpu),
|
|
mce_attributes[i]);
|
|
}
|
|
sysdev_unregister(&per_cpu(device_mce,cpu));
|
|
|
|
return err;
|
|
}
|
|
|
|
static void mce_remove_device(unsigned int cpu)
|
|
{
|
|
int i;
|
|
|
|
if (!cpu_isset(cpu, mce_device_initialized))
|
|
return;
|
|
|
|
for (i = 0; mce_attributes[i]; i++)
|
|
sysdev_remove_file(&per_cpu(device_mce,cpu),
|
|
mce_attributes[i]);
|
|
sysdev_unregister(&per_cpu(device_mce,cpu));
|
|
cpu_clear(cpu, mce_device_initialized);
|
|
}
|
|
|
|
/* 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;
|
|
|
|
switch (action) {
|
|
case CPU_ONLINE:
|
|
case CPU_ONLINE_FROZEN:
|
|
mce_create_device(cpu);
|
|
break;
|
|
case CPU_DEAD:
|
|
case CPU_DEAD_FROZEN:
|
|
mce_remove_device(cpu);
|
|
break;
|
|
}
|
|
return NOTIFY_OK;
|
|
}
|
|
|
|
static struct notifier_block mce_cpu_notifier __cpuinitdata = {
|
|
.notifier_call = mce_cpu_callback,
|
|
};
|
|
|
|
static __init int mce_init_device(void)
|
|
{
|
|
int err;
|
|
int i = 0;
|
|
|
|
if (!mce_available(&boot_cpu_data))
|
|
return -EIO;
|
|
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);
|