1 /* 2 * Bridge between MCE and APEI 3 * 4 * On some machine, corrected memory errors are reported via APEI 5 * generic hardware error source (GHES) instead of corrected Machine 6 * Check. These corrected memory errors can be reported to user space 7 * through /dev/mcelog via faking a corrected Machine Check, so that 8 * the error memory page can be offlined by /sbin/mcelog if the error 9 * count for one page is beyond the threshold. 10 * 11 * For fatal MCE, save MCE record into persistent storage via ERST, so 12 * that the MCE record can be logged after reboot via ERST. 13 * 14 * Copyright 2010 Intel Corp. 15 * Author: Huang Ying <ying.huang@intel.com> 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License version 19 * 2 as published by the Free Software Foundation. 20 * 21 * This program is distributed in the hope that it will be useful, 22 * but WITHOUT ANY WARRANTY; without even the implied warranty of 23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 24 * GNU General Public License for more details. 25 * 26 * You should have received a copy of the GNU General Public License 27 * along with this program; if not, write to the Free Software 28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 29 */ 30 31 #include <linux/export.h> 32 #include <linux/kernel.h> 33 #include <linux/acpi.h> 34 #include <linux/cper.h> 35 #include <acpi/apei.h> 36 #include <acpi/ghes.h> 37 #include <asm/mce.h> 38 39 #include "internal.h" 40 41 void apei_mce_report_mem_error(int severity, struct cper_sec_mem_err *mem_err) 42 { 43 struct mce m; 44 45 if (!(mem_err->validation_bits & CPER_MEM_VALID_PA)) 46 return; 47 48 mce_setup(&m); 49 m.bank = -1; 50 /* Fake a memory read error with unknown channel */ 51 m.status = MCI_STATUS_VAL | MCI_STATUS_EN | MCI_STATUS_ADDRV | 0x9f; 52 53 if (severity >= GHES_SEV_RECOVERABLE) 54 m.status |= MCI_STATUS_UC; 55 56 if (severity >= GHES_SEV_PANIC) { 57 m.status |= MCI_STATUS_PCC; 58 m.tsc = rdtsc(); 59 } 60 61 m.addr = mem_err->physical_addr; 62 mce_log(&m); 63 } 64 EXPORT_SYMBOL_GPL(apei_mce_report_mem_error); 65 66 #define CPER_CREATOR_MCE \ 67 UUID_LE(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \ 68 0x64, 0x90, 0xb8, 0x9d) 69 #define CPER_SECTION_TYPE_MCE \ 70 UUID_LE(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \ 71 0x04, 0x4a, 0x38, 0xfc) 72 73 /* 74 * CPER specification (in UEFI specification 2.3 appendix N) requires 75 * byte-packed. 76 */ 77 struct cper_mce_record { 78 struct cper_record_header hdr; 79 struct cper_section_descriptor sec_hdr; 80 struct mce mce; 81 } __packed; 82 83 int apei_write_mce(struct mce *m) 84 { 85 struct cper_mce_record rcd; 86 87 memset(&rcd, 0, sizeof(rcd)); 88 memcpy(rcd.hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE); 89 rcd.hdr.revision = CPER_RECORD_REV; 90 rcd.hdr.signature_end = CPER_SIG_END; 91 rcd.hdr.section_count = 1; 92 rcd.hdr.error_severity = CPER_SEV_FATAL; 93 /* timestamp, platform_id, partition_id are all invalid */ 94 rcd.hdr.validation_bits = 0; 95 rcd.hdr.record_length = sizeof(rcd); 96 rcd.hdr.creator_id = CPER_CREATOR_MCE; 97 rcd.hdr.notification_type = CPER_NOTIFY_MCE; 98 rcd.hdr.record_id = cper_next_record_id(); 99 rcd.hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR; 100 101 rcd.sec_hdr.section_offset = (void *)&rcd.mce - (void *)&rcd; 102 rcd.sec_hdr.section_length = sizeof(rcd.mce); 103 rcd.sec_hdr.revision = CPER_SEC_REV; 104 /* fru_id and fru_text is invalid */ 105 rcd.sec_hdr.validation_bits = 0; 106 rcd.sec_hdr.flags = CPER_SEC_PRIMARY; 107 rcd.sec_hdr.section_type = CPER_SECTION_TYPE_MCE; 108 rcd.sec_hdr.section_severity = CPER_SEV_FATAL; 109 110 memcpy(&rcd.mce, m, sizeof(*m)); 111 112 return erst_write(&rcd.hdr); 113 } 114 115 ssize_t apei_read_mce(struct mce *m, u64 *record_id) 116 { 117 struct cper_mce_record rcd; 118 int rc, pos; 119 120 rc = erst_get_record_id_begin(&pos); 121 if (rc) 122 return rc; 123 retry: 124 rc = erst_get_record_id_next(&pos, record_id); 125 if (rc) 126 goto out; 127 /* no more record */ 128 if (*record_id == APEI_ERST_INVALID_RECORD_ID) 129 goto out; 130 rc = erst_read(*record_id, &rcd.hdr, sizeof(rcd)); 131 /* someone else has cleared the record, try next one */ 132 if (rc == -ENOENT) 133 goto retry; 134 else if (rc < 0) 135 goto out; 136 /* try to skip other type records in storage */ 137 else if (rc != sizeof(rcd) || 138 uuid_le_cmp(rcd.hdr.creator_id, CPER_CREATOR_MCE)) 139 goto retry; 140 memcpy(m, &rcd.mce, sizeof(*m)); 141 rc = sizeof(*m); 142 out: 143 erst_get_record_id_end(); 144 145 return rc; 146 } 147 148 /* Check whether there is record in ERST */ 149 int apei_check_mce(void) 150 { 151 return erst_get_record_count(); 152 } 153 154 int apei_clear_mce(u64 record_id) 155 { 156 return erst_clear(record_id); 157 } 158