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 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
  91 static struct notifier_block nfit_mce_dec = {
  92         .notifier_call  = nfit_handle_mce,
  93 };
  94
  95 void nfit_mce_register(void)
  96 {
  97         mce_register_decode_chain(&nfit_mce_dec);
  98 }
  99
 100 void nfit_mce_unregister(void)
 101 {
 102         mce_unregister_decode_chain(&nfit_mce_dec);
 103 }