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 .priority = MCE_PRIO_NFIT, 94 }; 95 96 void nfit_mce_register(void) 97 { 98 mce_register_decode_chain(&nfit_mce_dec); 99 } 100 101 void nfit_mce_unregister(void) 102 { 103 mce_unregister_decode_chain(&nfit_mce_dec); 104 } 105