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
  21 static 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 uncorrectable memory errors */
  29         if (!mce_is_memory_error(mce) || mce_is_correctable(mce))
  30                 return NOTIFY_DONE;
  31
  32         /* Verify the address reported in the MCE is valid. */
  33         if (!mce_usable_address(mce))
  34                 return NOTIFY_DONE;
  35
  36         /*
  37          * mce->addr contains the physical addr accessed that caused the
  38          * machine check. We need to walk through the list of NFITs, and see
  39          * if any of them matches that address, and only then start a scrub.
  40          */
  41         mutex_lock(&acpi_desc_lock);
  42         list_for_each_entry(acpi_desc, &acpi_descs, list) {
  43                 struct device *dev = acpi_desc->dev;
  44                 int found_match = 0;
  45
  46                 mutex_lock(&acpi_desc->init_mutex);
  47                 list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
  48                         struct acpi_nfit_system_address *spa = nfit_spa->spa;
  49
  50                         if (nfit_spa_type(spa) != NFIT_SPA_PM)
  51                                 continue;
  52                         /* find the spa that covers the mce addr */
  53                         if (spa->address > mce->addr)
  54                                 continue;
  55                         if ((spa->address + spa->length - 1) < mce->addr)
  56                                 continue;
  57                         found_match = 1;
  58                         dev_dbg(dev, "addr in SPA %d (0x%llx, 0x%llx)\n",
  59                                 spa->range_index, spa->address, spa->length);
  60                         /*
  61                          * We can break at the first match because we're going
  62                          * to rescan all the SPA ranges. There shouldn't be any
  63                          * aliasing anyway.
  64                          */
  65                         break;
  66                 }
  67                 mutex_unlock(&acpi_desc->init_mutex);
  68
  69                 if (!found_match)
  70                         continue;
  71
  72                 /* If this fails due to an -ENOMEM, there is little we can do */
  73                 nvdimm_bus_add_badrange(acpi_desc->nvdimm_bus,
  74                                 ALIGN(mce->addr, L1_CACHE_BYTES),
  75                                 L1_CACHE_BYTES);
  76                 nvdimm_region_notify(nfit_spa->nd_region,
  77                                 NVDIMM_REVALIDATE_POISON);
  78
  79                 if (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON) {
  80                         /*
  81                          * We can ignore an -EBUSY here because if an ARS is
  82                          * already in progress, just let that be the last
  83                          * authoritative one
  84                          */
  85                         acpi_nfit_ars_rescan(acpi_desc, 0);
  86                 }
  87                 break;
  88         }
  89
  90         mutex_unlock(&acpi_desc_lock);
  91         return NOTIFY_DONE;
  92 }
  93
  94 static struct notifier_block nfit_mce_dec = {
  95         .notifier_call  = nfit_handle_mce,
  96         .priority       = MCE_PRIO_NFIT,
  97 };
  98
  99 void nfit_mce_register(void)
 100 {
 101         mce_register_decode_chain(&nfit_mce_dec);
 102 }
 103
 104 void nfit_mce_unregister(void)
 105 {
 106         mce_unregister_decode_chain(&nfit_mce_dec);
 107 }