drivers/acpi/nfit/mce.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * NFIT - Machine Check Handler
   4  *
   5  * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
   6  */
   7 #include <linux/notifier.h>
   8 #include <linux/acpi.h>
   9 #include <linux/nd.h>
  10 #include <asm/mce.h>
  11 #include "nfit.h"
  12
  13 static int nfit_handle_mce(struct notifier_block *nb, unsigned long val,
  14                         void *data)
  15 {
  16         struct mce *mce = (struct mce *)data;
  17         struct acpi_nfit_desc *acpi_desc;
  18         struct nfit_spa *nfit_spa;
  19
  20         /* We only care about uncorrectable memory errors */
  21         if (!mce_is_memory_error(mce) || mce_is_correctable(mce))
  22                 return NOTIFY_DONE;
  23
  24         /* Verify the address reported in the MCE is valid. */
  25         if (!mce_usable_address(mce))
  26                 return NOTIFY_DONE;
  27
  28         /*
  29          * mce->addr contains the physical addr accessed that caused the
  30          * machine check. We need to walk through the list of NFITs, and see
  31          * if any of them matches that address, and only then start a scrub.
  32          */
  33         mutex_lock(&acpi_desc_lock);
  34         list_for_each_entry(acpi_desc, &acpi_descs, list) {
  35                 struct device *dev = acpi_desc->dev;
  36                 int found_match = 0;
  37
  38                 mutex_lock(&acpi_desc->init_mutex);
  39                 list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
  40                         struct acpi_nfit_system_address *spa = nfit_spa->spa;
  41
  42                         if (nfit_spa_type(spa) != NFIT_SPA_PM)
  43                                 continue;
  44                         /* find the spa that covers the mce addr */
  45                         if (spa->address > mce->addr)
  46                                 continue;
  47                         if ((spa->address + spa->length - 1) < mce->addr)
  48                                 continue;
  49                         found_match = 1;
  50                         dev_dbg(dev, "addr in SPA %d (0x%llx, 0x%llx)\n",
  51                                 spa->range_index, spa->address, spa->length);
  52                         /*
  53                          * We can break at the first match because we're going
  54                          * to rescan all the SPA ranges. There shouldn't be any
  55                          * aliasing anyway.
  56                          */
  57                         break;
  58                 }
  59                 mutex_unlock(&acpi_desc->init_mutex);
  60
  61                 if (!found_match)
  62                         continue;
  63
  64                 /* If this fails due to an -ENOMEM, there is little we can do */
  65                 nvdimm_bus_add_badrange(acpi_desc->nvdimm_bus,
  66                                 ALIGN(mce->addr, L1_CACHE_BYTES),
  67                                 L1_CACHE_BYTES);
  68                 nvdimm_region_notify(nfit_spa->nd_region,
  69                                 NVDIMM_REVALIDATE_POISON);
  70
  71                 if (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON) {
  72                         /*
  73                          * We can ignore an -EBUSY here because if an ARS is
  74                          * already in progress, just let that be the last
  75                          * authoritative one
  76                          */
  77                         acpi_nfit_ars_rescan(acpi_desc, 0);
  78                 }
  79                 mce->kflags |= MCE_HANDLED_NFIT;
  80                 break;
  81         }
  82
  83         mutex_unlock(&acpi_desc_lock);
  84         return NOTIFY_DONE;
  85 }
  86
  87 static struct notifier_block nfit_mce_dec = {
  88         .notifier_call  = nfit_handle_mce,
  89         .priority       = MCE_PRIO_NFIT,
  90 };
  91
  92 void nfit_mce_register(void)
  93 {
  94         mce_register_decode_chain(&nfit_mce_dec);
  95 }
  96
  97 void nfit_mce_unregister(void)
  98 {
  99         mce_unregister_decode_chain(&nfit_mce_dec);
 100 }