1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Extended Error Log driver 4 * 5 * Copyright (C) 2013 Intel Corp. 6 * Author: Chen, Gong <gong.chen@intel.com> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/acpi.h> 11 #include <linux/cper.h> 12 #include <linux/ratelimit.h> 13 #include <linux/edac.h> 14 #include <linux/ras.h> 15 #include <acpi/ghes.h> 16 #include <asm/cpu.h> 17 #include <asm/mce.h> 18 19 #include "apei/apei-internal.h" 20 #include <ras/ras_event.h> 21 22 #define EXT_ELOG_ENTRY_MASK GENMASK_ULL(51, 0) /* elog entry address mask */ 23 24 #define EXTLOG_DSM_REV 0x0 25 #define EXTLOG_FN_ADDR 0x1 26 27 #define FLAG_OS_OPTIN BIT(0) 28 #define ELOG_ENTRY_VALID (1ULL<<63) 29 #define ELOG_ENTRY_LEN 0x1000 30 31 #define EMCA_BUG \ 32 "Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n" 33 34 struct extlog_l1_head { 35 u32 ver; /* Header Version */ 36 u32 hdr_len; /* Header Length */ 37 u64 total_len; /* entire L1 Directory length including this header */ 38 u64 elog_base; /* MCA Error Log Directory base address */ 39 u64 elog_len; /* MCA Error Log Directory length */ 40 u32 flags; /* bit 0 - OS/VMM Opt-in */ 41 u8 rev0[12]; 42 u32 entries; /* Valid L1 Directory entries per logical processor */ 43 u8 rev1[12]; 44 }; 45 46 static u8 extlog_dsm_uuid[] __initdata = "663E35AF-CC10-41A4-88EA-5470AF055295"; 47 48 /* L1 table related physical address */ 49 static u64 elog_base; 50 static size_t elog_size; 51 static u64 l1_dirbase; 52 static size_t l1_size; 53 54 /* L1 table related virtual address */ 55 static void __iomem *extlog_l1_addr; 56 static void __iomem *elog_addr; 57 58 static void *elog_buf; 59 60 static u64 *l1_entry_base; 61 static u32 l1_percpu_entry; 62 63 #define ELOG_IDX(cpu, bank) \ 64 (cpu_physical_id(cpu) * l1_percpu_entry + (bank)) 65 66 #define ELOG_ENTRY_DATA(idx) \ 67 (*(l1_entry_base + (idx))) 68 69 #define ELOG_ENTRY_ADDR(phyaddr) \ 70 (phyaddr - elog_base + (u8 *)elog_addr) 71 72 static struct acpi_hest_generic_status *extlog_elog_entry_check(int cpu, int bank) 73 { 74 int idx; 75 u64 data; 76 struct acpi_hest_generic_status *estatus; 77 78 WARN_ON(cpu < 0); 79 idx = ELOG_IDX(cpu, bank); 80 data = ELOG_ENTRY_DATA(idx); 81 if ((data & ELOG_ENTRY_VALID) == 0) 82 return NULL; 83 84 data &= EXT_ELOG_ENTRY_MASK; 85 estatus = (struct acpi_hest_generic_status *)ELOG_ENTRY_ADDR(data); 86 87 /* if no valid data in elog entry, just return */ 88 if (estatus->block_status == 0) 89 return NULL; 90 91 return estatus; 92 } 93 94 static void __print_extlog_rcd(const char *pfx, 95 struct acpi_hest_generic_status *estatus, int cpu) 96 { 97 static atomic_t seqno; 98 unsigned int curr_seqno; 99 char pfx_seq[64]; 100 101 if (!pfx) { 102 if (estatus->error_severity <= CPER_SEV_CORRECTED) 103 pfx = KERN_INFO; 104 else 105 pfx = KERN_ERR; 106 } 107 curr_seqno = atomic_inc_return(&seqno); 108 snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}", pfx, curr_seqno); 109 printk("%s""Hardware error detected on CPU%d\n", pfx_seq, cpu); 110 cper_estatus_print(pfx_seq, estatus); 111 } 112 113 static int print_extlog_rcd(const char *pfx, 114 struct acpi_hest_generic_status *estatus, int cpu) 115 { 116 /* Not more than 2 messages every 5 seconds */ 117 static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2); 118 static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2); 119 struct ratelimit_state *ratelimit; 120 121 if (estatus->error_severity == CPER_SEV_CORRECTED || 122 (estatus->error_severity == CPER_SEV_INFORMATIONAL)) 123 ratelimit = &ratelimit_corrected; 124 else 125 ratelimit = &ratelimit_uncorrected; 126 if (__ratelimit(ratelimit)) { 127 __print_extlog_rcd(pfx, estatus, cpu); 128 return 0; 129 } 130 131 return 1; 132 } 133 134 static int extlog_print(struct notifier_block *nb, unsigned long val, 135 void *data) 136 { 137 struct mce *mce = (struct mce *)data; 138 int bank = mce->bank; 139 int cpu = mce->extcpu; 140 struct acpi_hest_generic_status *estatus, *tmp; 141 struct acpi_hest_generic_data *gdata; 142 const guid_t *fru_id; 143 char *fru_text; 144 guid_t *sec_type; 145 static u32 err_seq; 146 147 estatus = extlog_elog_entry_check(cpu, bank); 148 if (!estatus) 149 return NOTIFY_DONE; 150 151 if (mce->kflags & MCE_HANDLED_CEC) { 152 estatus->block_status = 0; 153 return NOTIFY_DONE; 154 } 155 156 memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN); 157 /* clear record status to enable BIOS to update it again */ 158 estatus->block_status = 0; 159 160 tmp = (struct acpi_hest_generic_status *)elog_buf; 161 162 if (!ras_userspace_consumers()) { 163 print_extlog_rcd(NULL, tmp, cpu); 164 goto out; 165 } 166 167 /* log event via trace */ 168 err_seq++; 169 apei_estatus_for_each_section(tmp, gdata) { 170 if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID) 171 fru_id = (guid_t *)gdata->fru_id; 172 else 173 fru_id = &guid_null; 174 if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT) 175 fru_text = gdata->fru_text; 176 else 177 fru_text = ""; 178 sec_type = (guid_t *)gdata->section_type; 179 if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) { 180 struct cper_sec_mem_err *mem = acpi_hest_get_payload(gdata); 181 182 if (gdata->error_data_length >= sizeof(*mem)) 183 trace_extlog_mem_event(mem, err_seq, fru_id, fru_text, 184 (u8)gdata->error_severity); 185 } 186 } 187 188 out: 189 mce->kflags |= MCE_HANDLED_EXTLOG; 190 return NOTIFY_OK; 191 } 192 193 static bool __init extlog_get_l1addr(void) 194 { 195 guid_t guid; 196 acpi_handle handle; 197 union acpi_object *obj; 198 199 if (guid_parse(extlog_dsm_uuid, &guid)) 200 return false; 201 if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))) 202 return false; 203 if (!acpi_check_dsm(handle, &guid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR)) 204 return false; 205 obj = acpi_evaluate_dsm_typed(handle, &guid, EXTLOG_DSM_REV, 206 EXTLOG_FN_ADDR, NULL, ACPI_TYPE_INTEGER); 207 if (!obj) { 208 return false; 209 } else { 210 l1_dirbase = obj->integer.value; 211 ACPI_FREE(obj); 212 } 213 214 /* Spec says L1 directory must be 4K aligned, bail out if it isn't */ 215 if (l1_dirbase & ((1 << 12) - 1)) { 216 pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n", 217 l1_dirbase); 218 return false; 219 } 220 221 return true; 222 } 223 static struct notifier_block extlog_mce_dec = { 224 .notifier_call = extlog_print, 225 .priority = MCE_PRIO_EXTLOG, 226 }; 227 228 static int __init extlog_init(void) 229 { 230 struct extlog_l1_head *l1_head; 231 void __iomem *extlog_l1_hdr; 232 size_t l1_hdr_size; 233 struct resource *r; 234 u64 cap; 235 int rc; 236 237 if (rdmsrl_safe(MSR_IA32_MCG_CAP, &cap) || 238 !(cap & MCG_ELOG_P) || 239 !extlog_get_l1addr()) 240 return -ENODEV; 241 242 rc = -EINVAL; 243 /* get L1 header to fetch necessary information */ 244 l1_hdr_size = sizeof(struct extlog_l1_head); 245 r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR"); 246 if (!r) { 247 pr_warn(FW_BUG EMCA_BUG, 248 (unsigned long long)l1_dirbase, 249 (unsigned long long)l1_dirbase + l1_hdr_size); 250 goto err; 251 } 252 253 extlog_l1_hdr = acpi_os_map_iomem(l1_dirbase, l1_hdr_size); 254 l1_head = (struct extlog_l1_head *)extlog_l1_hdr; 255 l1_size = l1_head->total_len; 256 l1_percpu_entry = l1_head->entries; 257 elog_base = l1_head->elog_base; 258 elog_size = l1_head->elog_len; 259 acpi_os_unmap_iomem(extlog_l1_hdr, l1_hdr_size); 260 release_mem_region(l1_dirbase, l1_hdr_size); 261 262 /* remap L1 header again based on completed information */ 263 r = request_mem_region(l1_dirbase, l1_size, "L1 Table"); 264 if (!r) { 265 pr_warn(FW_BUG EMCA_BUG, 266 (unsigned long long)l1_dirbase, 267 (unsigned long long)l1_dirbase + l1_size); 268 goto err; 269 } 270 extlog_l1_addr = acpi_os_map_iomem(l1_dirbase, l1_size); 271 l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size); 272 273 /* remap elog table */ 274 r = request_mem_region(elog_base, elog_size, "Elog Table"); 275 if (!r) { 276 pr_warn(FW_BUG EMCA_BUG, 277 (unsigned long long)elog_base, 278 (unsigned long long)elog_base + elog_size); 279 goto err_release_l1_dir; 280 } 281 elog_addr = acpi_os_map_iomem(elog_base, elog_size); 282 283 rc = -ENOMEM; 284 /* allocate buffer to save elog record */ 285 elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL); 286 if (elog_buf == NULL) 287 goto err_release_elog; 288 289 mce_register_decode_chain(&extlog_mce_dec); 290 /* enable OS to be involved to take over management from BIOS */ 291 ((struct extlog_l1_head *)extlog_l1_addr)->flags |= FLAG_OS_OPTIN; 292 293 return 0; 294 295 err_release_elog: 296 if (elog_addr) 297 acpi_os_unmap_iomem(elog_addr, elog_size); 298 release_mem_region(elog_base, elog_size); 299 err_release_l1_dir: 300 if (extlog_l1_addr) 301 acpi_os_unmap_iomem(extlog_l1_addr, l1_size); 302 release_mem_region(l1_dirbase, l1_size); 303 err: 304 pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n"); 305 return rc; 306 } 307 308 static void __exit extlog_exit(void) 309 { 310 mce_unregister_decode_chain(&extlog_mce_dec); 311 if (extlog_l1_addr) { 312 ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; 313 acpi_os_unmap_iomem(extlog_l1_addr, l1_size); 314 } 315 if (elog_addr) 316 acpi_os_unmap_iomem(elog_addr, elog_size); 317 release_mem_region(elog_base, elog_size); 318 release_mem_region(l1_dirbase, l1_size); 319 kfree(elog_buf); 320 } 321 322 module_init(extlog_init); 323 module_exit(extlog_exit); 324 325 MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>"); 326 MODULE_DESCRIPTION("Extended MCA Error Log Driver"); 327 MODULE_LICENSE("GPL"); 328