LXR linux/drivers/acpi/nfit/mce.c

   1/*
   2 * NFIT - Machine Check Handler
   3 *
   4 * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of version 2 of the GNU General Public License as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful, but
  11 * WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 * General Public License for more details.
  14 */
  15#include <linux/notifier.h>
  16#include <linux/acpi.h>
  17#include <linux/nd.h>
  18#include <asm/mce.h>
  19#include "nfit.h"
  20
  21static int nfit_handle_mce(struct notifier_block *nb, unsigned long val,
  22                        void *data)
  23{
  24        struct mce *mce = (struct mce *)data;
  25        struct acpi_nfit_desc *acpi_desc;
  26        struct nfit_spa *nfit_spa;
  27
  28        /* We only care about memory errors */
  29        if (!(mce->status & MCACOD))
  30                return NOTIFY_DONE;
  31
  32        /*
  33         * mce->addr contains the physical addr accessed that caused the
  34         * machine check. We need to walk through the list of NFITs, and see
  35         * if any of them matches that address, and only then start a scrub.
  36         */
  37        mutex_lock(&acpi_desc_lock);
  38        list_for_each_entry(acpi_desc, &acpi_descs, list) {
  39                struct device *dev = acpi_desc->dev;
  40                int found_match = 0;
  41
  42                mutex_lock(&acpi_desc->init_mutex);
  43                list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
  44                        struct acpi_nfit_system_address *spa = nfit_spa->spa;
  45
  46                        if (nfit_spa_type(spa) != NFIT_SPA_PM)
  47                                continue;
  48                        /* find the spa that covers the mce addr */
  49                        if (spa->address > mce->addr)
  50                                continue;
  51                        if ((spa->address + spa->length - 1) < mce->addr)
  52                                continue;
  53                        found_match = 1;
  54                        dev_dbg(dev, "%s: addr in SPA %d (0x%llx, 0x%llx)\n",
  55                                __func__, spa->range_index, spa->address,
  56                                spa->length);
  57                        /*
  58                         * We can break at the first match because we're going
  59                         * to rescan all the SPA ranges. There shouldn't be any
  60                         * aliasing anyway.
  61                         */
  62                        break;
  63                }
  64                mutex_unlock(&acpi_desc->init_mutex);
  65
  66                if (!found_match)
  67                        continue;
  68
  69                /* If this fails due to an -ENOMEM, there is little we can do */
  70                nvdimm_bus_add_poison(acpi_desc->nvdimm_bus,
  71                                ALIGN(mce->addr, L1_CACHE_BYTES),
  72                                L1_CACHE_BYTES);
  73                nvdimm_region_notify(nfit_spa->nd_region,
  74                                NVDIMM_REVALIDATE_POISON);
  75
  76                if (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON) {
  77                        /*
  78                         * We can ignore an -EBUSY here because if an ARS is
  79                         * already in progress, just let that be the last
  80                         * authoritative one
  81                         */
  82                        acpi_nfit_ars_rescan(acpi_desc);
  83                }
  84                break;
  85        }
  86
  87        mutex_unlock(&acpi_desc_lock);
  88        return NOTIFY_DONE;
  89}
  90
  91static struct notifier_block nfit_mce_dec = {
  92        .notifier_call  = nfit_handle_mce,
  93};
  94
  95void nfit_mce_register(void)
  96{
  97        mce_register_decode_chain(&nfit_mce_dec);
  98}
  99
 100void nfit_mce_unregister(void)
 101{
 102        mce_unregister_decode_chain(&nfit_mce_dec);
 103}
 104