1 /* 2 * APEI Generic Hardware Error Source support 3 * 4 * Generic Hardware Error Source provides a way to report platform 5 * hardware errors (such as that from chipset). It works in so called 6 * "Firmware First" mode, that is, hardware errors are reported to 7 * firmware firstly, then reported to Linux by firmware. This way, 8 * some non-standard hardware error registers or non-standard hardware 9 * link can be checked by firmware to produce more hardware error 10 * information for Linux. 11 * 12 * For more information about Generic Hardware Error Source, please 13 * refer to ACPI Specification version 4.0, section 17.3.2.6 14 * 15 * Copyright 2010,2011 Intel Corp. 16 * Author: Huang Ying <ying.huang@intel.com> 17 * 18 * This program is free software; you can redistribute it and/or 19 * modify it under the terms of the GNU General Public License version 20 * 2 as published by the Free Software Foundation; 21 * 22 * This program is distributed in the hope that it will be useful, 23 * but WITHOUT ANY WARRANTY; without even the implied warranty of 24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 25 * GNU General Public License for more details. 26 */ 27 28 #include <linux/kernel.h> 29 #include <linux/moduleparam.h> 30 #include <linux/init.h> 31 #include <linux/acpi.h> 32 #include <linux/io.h> 33 #include <linux/interrupt.h> 34 #include <linux/timer.h> 35 #include <linux/cper.h> 36 #include <linux/kdebug.h> 37 #include <linux/platform_device.h> 38 #include <linux/mutex.h> 39 #include <linux/ratelimit.h> 40 #include <linux/vmalloc.h> 41 #include <linux/irq_work.h> 42 #include <linux/llist.h> 43 #include <linux/genalloc.h> 44 #include <linux/pci.h> 45 #include <linux/aer.h> 46 #include <linux/nmi.h> 47 #include <linux/sched/clock.h> 48 #include <linux/uuid.h> 49 #include <linux/ras.h> 50 51 #include <acpi/actbl1.h> 52 #include <acpi/ghes.h> 53 #include <acpi/apei.h> 54 #include <asm/fixmap.h> 55 #include <asm/tlbflush.h> 56 #include <ras/ras_event.h> 57 58 #include "apei-internal.h" 59 60 #define GHES_PFX "GHES: " 61 62 #define GHES_ESTATUS_MAX_SIZE 65536 63 #define GHES_ESOURCE_PREALLOC_MAX_SIZE 65536 64 65 #define GHES_ESTATUS_POOL_MIN_ALLOC_ORDER 3 66 67 /* This is just an estimation for memory pool allocation */ 68 #define GHES_ESTATUS_CACHE_AVG_SIZE 512 69 70 #define GHES_ESTATUS_CACHES_SIZE 4 71 72 #define GHES_ESTATUS_IN_CACHE_MAX_NSEC 10000000000ULL 73 /* Prevent too many caches are allocated because of RCU */ 74 #define GHES_ESTATUS_CACHE_ALLOCED_MAX (GHES_ESTATUS_CACHES_SIZE * 3 / 2) 75 76 #define GHES_ESTATUS_CACHE_LEN(estatus_len) \ 77 (sizeof(struct ghes_estatus_cache) + (estatus_len)) 78 #define GHES_ESTATUS_FROM_CACHE(estatus_cache) \ 79 ((struct acpi_hest_generic_status *) \ 80 ((struct ghes_estatus_cache *)(estatus_cache) + 1)) 81 82 #define GHES_ESTATUS_NODE_LEN(estatus_len) \ 83 (sizeof(struct ghes_estatus_node) + (estatus_len)) 84 #define GHES_ESTATUS_FROM_NODE(estatus_node) \ 85 ((struct acpi_hest_generic_status *) \ 86 ((struct ghes_estatus_node *)(estatus_node) + 1)) 87 88 static inline bool is_hest_type_generic_v2(struct ghes *ghes) 89 { 90 return ghes->generic->header.type == ACPI_HEST_TYPE_GENERIC_ERROR_V2; 91 } 92 93 /* 94 * This driver isn't really modular, however for the time being, 95 * continuing to use module_param is the easiest way to remain 96 * compatible with existing boot arg use cases. 97 */ 98 bool ghes_disable; 99 module_param_named(disable, ghes_disable, bool, 0); 100 101 /* 102 * All error sources notified with HED (Hardware Error Device) share a 103 * single notifier callback, so they need to be linked and checked one 104 * by one. This holds true for NMI too. 105 * 106 * RCU is used for these lists, so ghes_list_mutex is only used for 107 * list changing, not for traversing. 108 */ 109 static LIST_HEAD(ghes_hed); 110 static DEFINE_MUTEX(ghes_list_mutex); 111 112 /* 113 * Because the memory area used to transfer hardware error information 114 * from BIOS to Linux can be determined only in NMI, IRQ or timer 115 * handler, but general ioremap can not be used in atomic context, so 116 * the fixmap is used instead. 117 * 118 * These 2 spinlocks are used to prevent the fixmap entries from being used 119 * simultaneously. 120 */ 121 static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi); 122 static DEFINE_SPINLOCK(ghes_ioremap_lock_irq); 123 124 static struct gen_pool *ghes_estatus_pool; 125 static unsigned long ghes_estatus_pool_size_request; 126 127 static struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE]; 128 static atomic_t ghes_estatus_cache_alloced; 129 130 static int ghes_panic_timeout __read_mostly = 30; 131 132 static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn) 133 { 134 phys_addr_t paddr; 135 pgprot_t prot; 136 137 paddr = pfn << PAGE_SHIFT; 138 prot = arch_apei_get_mem_attribute(paddr); 139 __set_fixmap(FIX_APEI_GHES_NMI, paddr, prot); 140 141 return (void __iomem *) fix_to_virt(FIX_APEI_GHES_NMI); 142 } 143 144 static void __iomem *ghes_ioremap_pfn_irq(u64 pfn) 145 { 146 phys_addr_t paddr; 147 pgprot_t prot; 148 149 paddr = pfn << PAGE_SHIFT; 150 prot = arch_apei_get_mem_attribute(paddr); 151 __set_fixmap(FIX_APEI_GHES_IRQ, paddr, prot); 152 153 return (void __iomem *) fix_to_virt(FIX_APEI_GHES_IRQ); 154 } 155 156 static void ghes_iounmap_nmi(void) 157 { 158 clear_fixmap(FIX_APEI_GHES_NMI); 159 } 160 161 static void ghes_iounmap_irq(void) 162 { 163 clear_fixmap(FIX_APEI_GHES_IRQ); 164 } 165 166 static int ghes_estatus_pool_init(void) 167 { 168 ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1); 169 if (!ghes_estatus_pool) 170 return -ENOMEM; 171 return 0; 172 } 173 174 static void ghes_estatus_pool_free_chunk_page(struct gen_pool *pool, 175 struct gen_pool_chunk *chunk, 176 void *data) 177 { 178 free_page(chunk->start_addr); 179 } 180 181 static void ghes_estatus_pool_exit(void) 182 { 183 gen_pool_for_each_chunk(ghes_estatus_pool, 184 ghes_estatus_pool_free_chunk_page, NULL); 185 gen_pool_destroy(ghes_estatus_pool); 186 } 187 188 static int ghes_estatus_pool_expand(unsigned long len) 189 { 190 unsigned long i, pages, size, addr; 191 int ret; 192 193 ghes_estatus_pool_size_request += PAGE_ALIGN(len); 194 size = gen_pool_size(ghes_estatus_pool); 195 if (size >= ghes_estatus_pool_size_request) 196 return 0; 197 pages = (ghes_estatus_pool_size_request - size) / PAGE_SIZE; 198 for (i = 0; i < pages; i++) { 199 addr = __get_free_page(GFP_KERNEL); 200 if (!addr) 201 return -ENOMEM; 202 ret = gen_pool_add(ghes_estatus_pool, addr, PAGE_SIZE, -1); 203 if (ret) 204 return ret; 205 } 206 207 return 0; 208 } 209 210 static int map_gen_v2(struct ghes *ghes) 211 { 212 return apei_map_generic_address(&ghes->generic_v2->read_ack_register); 213 } 214 215 static void unmap_gen_v2(struct ghes *ghes) 216 { 217 apei_unmap_generic_address(&ghes->generic_v2->read_ack_register); 218 } 219 220 static struct ghes *ghes_new(struct acpi_hest_generic *generic) 221 { 222 struct ghes *ghes; 223 unsigned int error_block_length; 224 int rc; 225 226 ghes = kzalloc(sizeof(*ghes), GFP_KERNEL); 227 if (!ghes) 228 return ERR_PTR(-ENOMEM); 229 230 ghes->generic = generic; 231 if (is_hest_type_generic_v2(ghes)) { 232 rc = map_gen_v2(ghes); 233 if (rc) 234 goto err_free; 235 } 236 237 rc = apei_map_generic_address(&generic->error_status_address); 238 if (rc) 239 goto err_unmap_read_ack_addr; 240 error_block_length = generic->error_block_length; 241 if (error_block_length > GHES_ESTATUS_MAX_SIZE) { 242 pr_warning(FW_WARN GHES_PFX 243 "Error status block length is too long: %u for " 244 "generic hardware error source: %d.\n", 245 error_block_length, generic->header.source_id); 246 error_block_length = GHES_ESTATUS_MAX_SIZE; 247 } 248 ghes->estatus = kmalloc(error_block_length, GFP_KERNEL); 249 if (!ghes->estatus) { 250 rc = -ENOMEM; 251 goto err_unmap_status_addr; 252 } 253 254 return ghes; 255 256 err_unmap_status_addr: 257 apei_unmap_generic_address(&generic->error_status_address); 258 err_unmap_read_ack_addr: 259 if (is_hest_type_generic_v2(ghes)) 260 unmap_gen_v2(ghes); 261 err_free: 262 kfree(ghes); 263 return ERR_PTR(rc); 264 } 265 266 static void ghes_fini(struct ghes *ghes) 267 { 268 kfree(ghes->estatus); 269 apei_unmap_generic_address(&ghes->generic->error_status_address); 270 if (is_hest_type_generic_v2(ghes)) 271 unmap_gen_v2(ghes); 272 } 273 274 static inline int ghes_severity(int severity) 275 { 276 switch (severity) { 277 case CPER_SEV_INFORMATIONAL: 278 return GHES_SEV_NO; 279 case CPER_SEV_CORRECTED: 280 return GHES_SEV_CORRECTED; 281 case CPER_SEV_RECOVERABLE: 282 return GHES_SEV_RECOVERABLE; 283 case CPER_SEV_FATAL: 284 return GHES_SEV_PANIC; 285 default: 286 /* Unknown, go panic */ 287 return GHES_SEV_PANIC; 288 } 289 } 290 291 static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, 292 int from_phys) 293 { 294 void __iomem *vaddr; 295 unsigned long flags = 0; 296 int in_nmi = in_nmi(); 297 u64 offset; 298 u32 trunk; 299 300 while (len > 0) { 301 offset = paddr - (paddr & PAGE_MASK); 302 if (in_nmi) { 303 raw_spin_lock(&ghes_ioremap_lock_nmi); 304 vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT); 305 } else { 306 spin_lock_irqsave(&ghes_ioremap_lock_irq, flags); 307 vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT); 308 } 309 trunk = PAGE_SIZE - offset; 310 trunk = min(trunk, len); 311 if (from_phys) 312 memcpy_fromio(buffer, vaddr + offset, trunk); 313 else 314 memcpy_toio(vaddr + offset, buffer, trunk); 315 len -= trunk; 316 paddr += trunk; 317 buffer += trunk; 318 if (in_nmi) { 319 ghes_iounmap_nmi(); 320 raw_spin_unlock(&ghes_ioremap_lock_nmi); 321 } else { 322 ghes_iounmap_irq(); 323 spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags); 324 } 325 } 326 } 327 328 static int ghes_read_estatus(struct ghes *ghes, int silent) 329 { 330 struct acpi_hest_generic *g = ghes->generic; 331 u64 buf_paddr; 332 u32 len; 333 int rc; 334 335 rc = apei_read(&buf_paddr, &g->error_status_address); 336 if (rc) { 337 if (!silent && printk_ratelimit()) 338 pr_warning(FW_WARN GHES_PFX 339 "Failed to read error status block address for hardware error source: %d.\n", 340 g->header.source_id); 341 return -EIO; 342 } 343 if (!buf_paddr) 344 return -ENOENT; 345 346 ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, 347 sizeof(*ghes->estatus), 1); 348 if (!ghes->estatus->block_status) 349 return -ENOENT; 350 351 ghes->buffer_paddr = buf_paddr; 352 ghes->flags |= GHES_TO_CLEAR; 353 354 rc = -EIO; 355 len = cper_estatus_len(ghes->estatus); 356 if (len < sizeof(*ghes->estatus)) 357 goto err_read_block; 358 if (len > ghes->generic->error_block_length) 359 goto err_read_block; 360 if (cper_estatus_check_header(ghes->estatus)) 361 goto err_read_block; 362 ghes_copy_tofrom_phys(ghes->estatus + 1, 363 buf_paddr + sizeof(*ghes->estatus), 364 len - sizeof(*ghes->estatus), 1); 365 if (cper_estatus_check(ghes->estatus)) 366 goto err_read_block; 367 rc = 0; 368 369 err_read_block: 370 if (rc && !silent && printk_ratelimit()) 371 pr_warning(FW_WARN GHES_PFX 372 "Failed to read error status block!\n"); 373 return rc; 374 } 375 376 static void ghes_clear_estatus(struct ghes *ghes) 377 { 378 ghes->estatus->block_status = 0; 379 if (!(ghes->flags & GHES_TO_CLEAR)) 380 return; 381 ghes_copy_tofrom_phys(ghes->estatus, ghes->buffer_paddr, 382 sizeof(ghes->estatus->block_status), 0); 383 ghes->flags &= ~GHES_TO_CLEAR; 384 } 385 386 static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int sev) 387 { 388 #ifdef CONFIG_ACPI_APEI_MEMORY_FAILURE 389 unsigned long pfn; 390 int flags = -1; 391 int sec_sev = ghes_severity(gdata->error_severity); 392 struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata); 393 394 if (!(mem_err->validation_bits & CPER_MEM_VALID_PA)) 395 return; 396 397 pfn = mem_err->physical_addr >> PAGE_SHIFT; 398 if (!pfn_valid(pfn)) { 399 pr_warn_ratelimited(FW_WARN GHES_PFX 400 "Invalid address in generic error data: %#llx\n", 401 mem_err->physical_addr); 402 return; 403 } 404 405 /* iff following two events can be handled properly by now */ 406 if (sec_sev == GHES_SEV_CORRECTED && 407 (gdata->flags & CPER_SEC_ERROR_THRESHOLD_EXCEEDED)) 408 flags = MF_SOFT_OFFLINE; 409 if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE) 410 flags = 0; 411 412 if (flags != -1) 413 memory_failure_queue(pfn, 0, flags); 414 #endif 415 } 416 417 static void ghes_do_proc(struct ghes *ghes, 418 const struct acpi_hest_generic_status *estatus) 419 { 420 int sev, sec_sev; 421 struct acpi_hest_generic_data *gdata; 422 guid_t *sec_type; 423 guid_t *fru_id = &NULL_UUID_LE; 424 char *fru_text = ""; 425 426 sev = ghes_severity(estatus->error_severity); 427 apei_estatus_for_each_section(estatus, gdata) { 428 sec_type = (guid_t *)gdata->section_type; 429 sec_sev = ghes_severity(gdata->error_severity); 430 if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID) 431 fru_id = (guid_t *)gdata->fru_id; 432 433 if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT) 434 fru_text = gdata->fru_text; 435 436 if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) { 437 struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata); 438 439 ghes_edac_report_mem_error(ghes, sev, mem_err); 440 441 arch_apei_report_mem_error(sev, mem_err); 442 ghes_handle_memory_failure(gdata, sev); 443 } 444 #ifdef CONFIG_ACPI_APEI_PCIEAER 445 else if (guid_equal(sec_type, &CPER_SEC_PCIE)) { 446 struct cper_sec_pcie *pcie_err = acpi_hest_get_payload(gdata); 447 448 if (sev == GHES_SEV_RECOVERABLE && 449 sec_sev == GHES_SEV_RECOVERABLE && 450 pcie_err->validation_bits & CPER_PCIE_VALID_DEVICE_ID && 451 pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) { 452 unsigned int devfn; 453 int aer_severity; 454 455 devfn = PCI_DEVFN(pcie_err->device_id.device, 456 pcie_err->device_id.function); 457 aer_severity = cper_severity_to_aer(gdata->error_severity); 458 459 /* 460 * If firmware reset the component to contain 461 * the error, we must reinitialize it before 462 * use, so treat it as a fatal AER error. 463 */ 464 if (gdata->flags & CPER_SEC_RESET) 465 aer_severity = AER_FATAL; 466 467 aer_recover_queue(pcie_err->device_id.segment, 468 pcie_err->device_id.bus, 469 devfn, aer_severity, 470 (struct aer_capability_regs *) 471 pcie_err->aer_info); 472 } 473 474 } 475 #endif 476 else if (guid_equal(sec_type, &CPER_SEC_PROC_ARM)) { 477 struct cper_sec_proc_arm *err = acpi_hest_get_payload(gdata); 478 479 log_arm_hw_error(err); 480 } else { 481 void *err = acpi_hest_get_payload(gdata); 482 483 log_non_standard_event(sec_type, fru_id, fru_text, 484 sec_sev, err, 485 gdata->error_data_length); 486 } 487 } 488 } 489 490 static void __ghes_print_estatus(const char *pfx, 491 const struct acpi_hest_generic *generic, 492 const struct acpi_hest_generic_status *estatus) 493 { 494 static atomic_t seqno; 495 unsigned int curr_seqno; 496 char pfx_seq[64]; 497 498 if (pfx == NULL) { 499 if (ghes_severity(estatus->error_severity) <= 500 GHES_SEV_CORRECTED) 501 pfx = KERN_WARNING; 502 else 503 pfx = KERN_ERR; 504 } 505 curr_seqno = atomic_inc_return(&seqno); 506 snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}" HW_ERR, pfx, curr_seqno); 507 printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n", 508 pfx_seq, generic->header.source_id); 509 cper_estatus_print(pfx_seq, estatus); 510 } 511 512 static int ghes_print_estatus(const char *pfx, 513 const struct acpi_hest_generic *generic, 514 const struct acpi_hest_generic_status *estatus) 515 { 516 /* Not more than 2 messages every 5 seconds */ 517 static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2); 518 static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2); 519 struct ratelimit_state *ratelimit; 520 521 if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED) 522 ratelimit = &ratelimit_corrected; 523 else 524 ratelimit = &ratelimit_uncorrected; 525 if (__ratelimit(ratelimit)) { 526 __ghes_print_estatus(pfx, generic, estatus); 527 return 1; 528 } 529 return 0; 530 } 531 532 /* 533 * GHES error status reporting throttle, to report more kinds of 534 * errors, instead of just most frequently occurred errors. 535 */ 536 static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus) 537 { 538 u32 len; 539 int i, cached = 0; 540 unsigned long long now; 541 struct ghes_estatus_cache *cache; 542 struct acpi_hest_generic_status *cache_estatus; 543 544 len = cper_estatus_len(estatus); 545 rcu_read_lock(); 546 for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { 547 cache = rcu_dereference(ghes_estatus_caches[i]); 548 if (cache == NULL) 549 continue; 550 if (len != cache->estatus_len) 551 continue; 552 cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); 553 if (memcmp(estatus, cache_estatus, len)) 554 continue; 555 atomic_inc(&cache->count); 556 now = sched_clock(); 557 if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC) 558 cached = 1; 559 break; 560 } 561 rcu_read_unlock(); 562 return cached; 563 } 564 565 static struct ghes_estatus_cache *ghes_estatus_cache_alloc( 566 struct acpi_hest_generic *generic, 567 struct acpi_hest_generic_status *estatus) 568 { 569 int alloced; 570 u32 len, cache_len; 571 struct ghes_estatus_cache *cache; 572 struct acpi_hest_generic_status *cache_estatus; 573 574 alloced = atomic_add_return(1, &ghes_estatus_cache_alloced); 575 if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) { 576 atomic_dec(&ghes_estatus_cache_alloced); 577 return NULL; 578 } 579 len = cper_estatus_len(estatus); 580 cache_len = GHES_ESTATUS_CACHE_LEN(len); 581 cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len); 582 if (!cache) { 583 atomic_dec(&ghes_estatus_cache_alloced); 584 return NULL; 585 } 586 cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); 587 memcpy(cache_estatus, estatus, len); 588 cache->estatus_len = len; 589 atomic_set(&cache->count, 0); 590 cache->generic = generic; 591 cache->time_in = sched_clock(); 592 return cache; 593 } 594 595 static void ghes_estatus_cache_free(struct ghes_estatus_cache *cache) 596 { 597 u32 len; 598 599 len = cper_estatus_len(GHES_ESTATUS_FROM_CACHE(cache)); 600 len = GHES_ESTATUS_CACHE_LEN(len); 601 gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len); 602 atomic_dec(&ghes_estatus_cache_alloced); 603 } 604 605 static void ghes_estatus_cache_rcu_free(struct rcu_head *head) 606 { 607 struct ghes_estatus_cache *cache; 608 609 cache = container_of(head, struct ghes_estatus_cache, rcu); 610 ghes_estatus_cache_free(cache); 611 } 612 613 static void ghes_estatus_cache_add( 614 struct acpi_hest_generic *generic, 615 struct acpi_hest_generic_status *estatus) 616 { 617 int i, slot = -1, count; 618 unsigned long long now, duration, period, max_period = 0; 619 struct ghes_estatus_cache *cache, *slot_cache = NULL, *new_cache; 620 621 new_cache = ghes_estatus_cache_alloc(generic, estatus); 622 if (new_cache == NULL) 623 return; 624 rcu_read_lock(); 625 now = sched_clock(); 626 for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { 627 cache = rcu_dereference(ghes_estatus_caches[i]); 628 if (cache == NULL) { 629 slot = i; 630 slot_cache = NULL; 631 break; 632 } 633 duration = now - cache->time_in; 634 if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) { 635 slot = i; 636 slot_cache = cache; 637 break; 638 } 639 count = atomic_read(&cache->count); 640 period = duration; 641 do_div(period, (count + 1)); 642 if (period > max_period) { 643 max_period = period; 644 slot = i; 645 slot_cache = cache; 646 } 647 } 648 /* new_cache must be put into array after its contents are written */ 649 smp_wmb(); 650 if (slot != -1 && cmpxchg(ghes_estatus_caches + slot, 651 slot_cache, new_cache) == slot_cache) { 652 if (slot_cache) 653 call_rcu(&slot_cache->rcu, ghes_estatus_cache_rcu_free); 654 } else 655 ghes_estatus_cache_free(new_cache); 656 rcu_read_unlock(); 657 } 658 659 static int ghes_ack_error(struct acpi_hest_generic_v2 *gv2) 660 { 661 int rc; 662 u64 val = 0; 663 664 rc = apei_read(&val, &gv2->read_ack_register); 665 if (rc) 666 return rc; 667 668 val &= gv2->read_ack_preserve << gv2->read_ack_register.bit_offset; 669 val |= gv2->read_ack_write << gv2->read_ack_register.bit_offset; 670 671 return apei_write(val, &gv2->read_ack_register); 672 } 673 674 static void __ghes_panic(struct ghes *ghes) 675 { 676 __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); 677 678 /* reboot to log the error! */ 679 if (!panic_timeout) 680 panic_timeout = ghes_panic_timeout; 681 panic("Fatal hardware error!"); 682 } 683 684 static int ghes_proc(struct ghes *ghes) 685 { 686 int rc; 687 688 rc = ghes_read_estatus(ghes, 0); 689 if (rc) 690 goto out; 691 692 if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) { 693 __ghes_panic(ghes); 694 } 695 696 if (!ghes_estatus_cached(ghes->estatus)) { 697 if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) 698 ghes_estatus_cache_add(ghes->generic, ghes->estatus); 699 } 700 ghes_do_proc(ghes, ghes->estatus); 701 702 out: 703 ghes_clear_estatus(ghes); 704 705 if (rc == -ENOENT) 706 return rc; 707 708 /* 709 * GHESv2 type HEST entries introduce support for error acknowledgment, 710 * so only acknowledge the error if this support is present. 711 */ 712 if (is_hest_type_generic_v2(ghes)) 713 return ghes_ack_error(ghes->generic_v2); 714 715 return rc; 716 } 717 718 static void ghes_add_timer(struct ghes *ghes) 719 { 720 struct acpi_hest_generic *g = ghes->generic; 721 unsigned long expire; 722 723 if (!g->notify.poll_interval) { 724 pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n", 725 g->header.source_id); 726 return; 727 } 728 expire = jiffies + msecs_to_jiffies(g->notify.poll_interval); 729 ghes->timer.expires = round_jiffies_relative(expire); 730 add_timer(&ghes->timer); 731 } 732 733 static void ghes_poll_func(struct timer_list *t) 734 { 735 struct ghes *ghes = from_timer(ghes, t, timer); 736 737 ghes_proc(ghes); 738 if (!(ghes->flags & GHES_EXITING)) 739 ghes_add_timer(ghes); 740 } 741 742 static irqreturn_t ghes_irq_func(int irq, void *data) 743 { 744 struct ghes *ghes = data; 745 int rc; 746 747 rc = ghes_proc(ghes); 748 if (rc) 749 return IRQ_NONE; 750 751 return IRQ_HANDLED; 752 } 753 754 static int ghes_notify_hed(struct notifier_block *this, unsigned long event, 755 void *data) 756 { 757 struct ghes *ghes; 758 int ret = NOTIFY_DONE; 759 760 rcu_read_lock(); 761 list_for_each_entry_rcu(ghes, &ghes_hed, list) { 762 if (!ghes_proc(ghes)) 763 ret = NOTIFY_OK; 764 } 765 rcu_read_unlock(); 766 767 return ret; 768 } 769 770 static struct notifier_block ghes_notifier_hed = { 771 .notifier_call = ghes_notify_hed, 772 }; 773 774 #ifdef CONFIG_ACPI_APEI_SEA 775 static LIST_HEAD(ghes_sea); 776 777 /* 778 * Return 0 only if one of the SEA error sources successfully reported an error 779 * record sent from the firmware. 780 */ 781 int ghes_notify_sea(void) 782 { 783 struct ghes *ghes; 784 int ret = -ENOENT; 785 786 rcu_read_lock(); 787 list_for_each_entry_rcu(ghes, &ghes_sea, list) { 788 if (!ghes_proc(ghes)) 789 ret = 0; 790 } 791 rcu_read_unlock(); 792 return ret; 793 } 794 795 static void ghes_sea_add(struct ghes *ghes) 796 { 797 mutex_lock(&ghes_list_mutex); 798 list_add_rcu(&ghes->list, &ghes_sea); 799 mutex_unlock(&ghes_list_mutex); 800 } 801 802 static void ghes_sea_remove(struct ghes *ghes) 803 { 804 mutex_lock(&ghes_list_mutex); 805 list_del_rcu(&ghes->list); 806 mutex_unlock(&ghes_list_mutex); 807 synchronize_rcu(); 808 } 809 #else /* CONFIG_ACPI_APEI_SEA */ 810 static inline void ghes_sea_add(struct ghes *ghes) { } 811 static inline void ghes_sea_remove(struct ghes *ghes) { } 812 #endif /* CONFIG_ACPI_APEI_SEA */ 813 814 #ifdef CONFIG_HAVE_ACPI_APEI_NMI 815 /* 816 * printk is not safe in NMI context. So in NMI handler, we allocate 817 * required memory from lock-less memory allocator 818 * (ghes_estatus_pool), save estatus into it, put them into lock-less 819 * list (ghes_estatus_llist), then delay printk into IRQ context via 820 * irq_work (ghes_proc_irq_work). ghes_estatus_size_request record 821 * required pool size by all NMI error source. 822 */ 823 static struct llist_head ghes_estatus_llist; 824 static struct irq_work ghes_proc_irq_work; 825 826 /* 827 * NMI may be triggered on any CPU, so ghes_in_nmi is used for 828 * having only one concurrent reader. 829 */ 830 static atomic_t ghes_in_nmi = ATOMIC_INIT(0); 831 832 static LIST_HEAD(ghes_nmi); 833 834 static void ghes_proc_in_irq(struct irq_work *irq_work) 835 { 836 struct llist_node *llnode, *next; 837 struct ghes_estatus_node *estatus_node; 838 struct acpi_hest_generic *generic; 839 struct acpi_hest_generic_status *estatus; 840 u32 len, node_len; 841 842 llnode = llist_del_all(&ghes_estatus_llist); 843 /* 844 * Because the time order of estatus in list is reversed, 845 * revert it back to proper order. 846 */ 847 llnode = llist_reverse_order(llnode); 848 while (llnode) { 849 next = llnode->next; 850 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 851 llnode); 852 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 853 len = cper_estatus_len(estatus); 854 node_len = GHES_ESTATUS_NODE_LEN(len); 855 ghes_do_proc(estatus_node->ghes, estatus); 856 if (!ghes_estatus_cached(estatus)) { 857 generic = estatus_node->generic; 858 if (ghes_print_estatus(NULL, generic, estatus)) 859 ghes_estatus_cache_add(generic, estatus); 860 } 861 gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, 862 node_len); 863 llnode = next; 864 } 865 } 866 867 static void ghes_print_queued_estatus(void) 868 { 869 struct llist_node *llnode; 870 struct ghes_estatus_node *estatus_node; 871 struct acpi_hest_generic *generic; 872 struct acpi_hest_generic_status *estatus; 873 u32 len, node_len; 874 875 llnode = llist_del_all(&ghes_estatus_llist); 876 /* 877 * Because the time order of estatus in list is reversed, 878 * revert it back to proper order. 879 */ 880 llnode = llist_reverse_order(llnode); 881 while (llnode) { 882 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 883 llnode); 884 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 885 len = cper_estatus_len(estatus); 886 node_len = GHES_ESTATUS_NODE_LEN(len); 887 generic = estatus_node->generic; 888 ghes_print_estatus(NULL, generic, estatus); 889 llnode = llnode->next; 890 } 891 } 892 893 /* Save estatus for further processing in IRQ context */ 894 static void __process_error(struct ghes *ghes) 895 { 896 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 897 u32 len, node_len; 898 struct ghes_estatus_node *estatus_node; 899 struct acpi_hest_generic_status *estatus; 900 901 if (ghes_estatus_cached(ghes->estatus)) 902 return; 903 904 len = cper_estatus_len(ghes->estatus); 905 node_len = GHES_ESTATUS_NODE_LEN(len); 906 907 estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); 908 if (!estatus_node) 909 return; 910 911 estatus_node->ghes = ghes; 912 estatus_node->generic = ghes->generic; 913 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 914 memcpy(estatus, ghes->estatus, len); 915 llist_add(&estatus_node->llnode, &ghes_estatus_llist); 916 #endif 917 } 918 919 static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) 920 { 921 struct ghes *ghes; 922 int sev, ret = NMI_DONE; 923 924 if (!atomic_add_unless(&ghes_in_nmi, 1, 1)) 925 return ret; 926 927 list_for_each_entry_rcu(ghes, &ghes_nmi, list) { 928 if (ghes_read_estatus(ghes, 1)) { 929 ghes_clear_estatus(ghes); 930 continue; 931 } else { 932 ret = NMI_HANDLED; 933 } 934 935 sev = ghes_severity(ghes->estatus->error_severity); 936 if (sev >= GHES_SEV_PANIC) { 937 oops_begin(); 938 ghes_print_queued_estatus(); 939 __ghes_panic(ghes); 940 } 941 942 if (!(ghes->flags & GHES_TO_CLEAR)) 943 continue; 944 945 __process_error(ghes); 946 ghes_clear_estatus(ghes); 947 } 948 949 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 950 if (ret == NMI_HANDLED) 951 irq_work_queue(&ghes_proc_irq_work); 952 #endif 953 atomic_dec(&ghes_in_nmi); 954 return ret; 955 } 956 957 static unsigned long ghes_esource_prealloc_size( 958 const struct acpi_hest_generic *generic) 959 { 960 unsigned long block_length, prealloc_records, prealloc_size; 961 962 block_length = min_t(unsigned long, generic->error_block_length, 963 GHES_ESTATUS_MAX_SIZE); 964 prealloc_records = max_t(unsigned long, 965 generic->records_to_preallocate, 1); 966 prealloc_size = min_t(unsigned long, block_length * prealloc_records, 967 GHES_ESOURCE_PREALLOC_MAX_SIZE); 968 969 return prealloc_size; 970 } 971 972 static void ghes_estatus_pool_shrink(unsigned long len) 973 { 974 ghes_estatus_pool_size_request -= PAGE_ALIGN(len); 975 } 976 977 static void ghes_nmi_add(struct ghes *ghes) 978 { 979 unsigned long len; 980 981 len = ghes_esource_prealloc_size(ghes->generic); 982 ghes_estatus_pool_expand(len); 983 mutex_lock(&ghes_list_mutex); 984 if (list_empty(&ghes_nmi)) 985 register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes"); 986 list_add_rcu(&ghes->list, &ghes_nmi); 987 mutex_unlock(&ghes_list_mutex); 988 } 989 990 static void ghes_nmi_remove(struct ghes *ghes) 991 { 992 unsigned long len; 993 994 mutex_lock(&ghes_list_mutex); 995 list_del_rcu(&ghes->list); 996 if (list_empty(&ghes_nmi)) 997 unregister_nmi_handler(NMI_LOCAL, "ghes"); 998 mutex_unlock(&ghes_list_mutex); 999 /* 1000 * To synchronize with NMI handler, ghes can only be 1001 * freed after NMI handler finishes. 1002 */ 1003 synchronize_rcu(); 1004 len = ghes_esource_prealloc_size(ghes->generic); 1005 ghes_estatus_pool_shrink(len); 1006 } 1007 1008 static void ghes_nmi_init_cxt(void) 1009 { 1010 init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq); 1011 } 1012 #else /* CONFIG_HAVE_ACPI_APEI_NMI */ 1013 static inline void ghes_nmi_add(struct ghes *ghes) { } 1014 static inline void ghes_nmi_remove(struct ghes *ghes) { } 1015 static inline void ghes_nmi_init_cxt(void) { } 1016 #endif /* CONFIG_HAVE_ACPI_APEI_NMI */ 1017 1018 static int ghes_probe(struct platform_device *ghes_dev) 1019 { 1020 struct acpi_hest_generic *generic; 1021 struct ghes *ghes = NULL; 1022 1023 int rc = -EINVAL; 1024 1025 generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data; 1026 if (!generic->enabled) 1027 return -ENODEV; 1028 1029 switch (generic->notify.type) { 1030 case ACPI_HEST_NOTIFY_POLLED: 1031 case ACPI_HEST_NOTIFY_EXTERNAL: 1032 case ACPI_HEST_NOTIFY_SCI: 1033 case ACPI_HEST_NOTIFY_GSIV: 1034 case ACPI_HEST_NOTIFY_GPIO: 1035 break; 1036 1037 case ACPI_HEST_NOTIFY_SEA: 1038 if (!IS_ENABLED(CONFIG_ACPI_APEI_SEA)) { 1039 pr_warn(GHES_PFX "Generic hardware error source: %d notified via SEA is not supported\n", 1040 generic->header.source_id); 1041 rc = -ENOTSUPP; 1042 goto err; 1043 } 1044 break; 1045 case ACPI_HEST_NOTIFY_NMI: 1046 if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) { 1047 pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n", 1048 generic->header.source_id); 1049 goto err; 1050 } 1051 break; 1052 case ACPI_HEST_NOTIFY_LOCAL: 1053 pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n", 1054 generic->header.source_id); 1055 goto err; 1056 default: 1057 pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n", 1058 generic->notify.type, generic->header.source_id); 1059 goto err; 1060 } 1061 1062 rc = -EIO; 1063 if (generic->error_block_length < 1064 sizeof(struct acpi_hest_generic_status)) { 1065 pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n", 1066 generic->error_block_length, 1067 generic->header.source_id); 1068 goto err; 1069 } 1070 ghes = ghes_new(generic); 1071 if (IS_ERR(ghes)) { 1072 rc = PTR_ERR(ghes); 1073 ghes = NULL; 1074 goto err; 1075 } 1076 1077 rc = ghes_edac_register(ghes, &ghes_dev->dev); 1078 if (rc < 0) 1079 goto err; 1080 1081 switch (generic->notify.type) { 1082 case ACPI_HEST_NOTIFY_POLLED: 1083 timer_setup(&ghes->timer, ghes_poll_func, TIMER_DEFERRABLE); 1084 ghes_add_timer(ghes); 1085 break; 1086 case ACPI_HEST_NOTIFY_EXTERNAL: 1087 /* External interrupt vector is GSI */ 1088 rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq); 1089 if (rc) { 1090 pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n", 1091 generic->header.source_id); 1092 goto err_edac_unreg; 1093 } 1094 rc = request_irq(ghes->irq, ghes_irq_func, IRQF_SHARED, 1095 "GHES IRQ", ghes); 1096 if (rc) { 1097 pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n", 1098 generic->header.source_id); 1099 goto err_edac_unreg; 1100 } 1101 break; 1102 1103 case ACPI_HEST_NOTIFY_SCI: 1104 case ACPI_HEST_NOTIFY_GSIV: 1105 case ACPI_HEST_NOTIFY_GPIO: 1106 mutex_lock(&ghes_list_mutex); 1107 if (list_empty(&ghes_hed)) 1108 register_acpi_hed_notifier(&ghes_notifier_hed); 1109 list_add_rcu(&ghes->list, &ghes_hed); 1110 mutex_unlock(&ghes_list_mutex); 1111 break; 1112 1113 case ACPI_HEST_NOTIFY_SEA: 1114 ghes_sea_add(ghes); 1115 break; 1116 case ACPI_HEST_NOTIFY_NMI: 1117 ghes_nmi_add(ghes); 1118 break; 1119 default: 1120 BUG(); 1121 } 1122 platform_set_drvdata(ghes_dev, ghes); 1123 1124 /* Handle any pending errors right away */ 1125 ghes_proc(ghes); 1126 1127 return 0; 1128 err_edac_unreg: 1129 ghes_edac_unregister(ghes); 1130 err: 1131 if (ghes) { 1132 ghes_fini(ghes); 1133 kfree(ghes); 1134 } 1135 return rc; 1136 } 1137 1138 static int ghes_remove(struct platform_device *ghes_dev) 1139 { 1140 struct ghes *ghes; 1141 struct acpi_hest_generic *generic; 1142 1143 ghes = platform_get_drvdata(ghes_dev); 1144 generic = ghes->generic; 1145 1146 ghes->flags |= GHES_EXITING; 1147 switch (generic->notify.type) { 1148 case ACPI_HEST_NOTIFY_POLLED: 1149 del_timer_sync(&ghes->timer); 1150 break; 1151 case ACPI_HEST_NOTIFY_EXTERNAL: 1152 free_irq(ghes->irq, ghes); 1153 break; 1154 1155 case ACPI_HEST_NOTIFY_SCI: 1156 case ACPI_HEST_NOTIFY_GSIV: 1157 case ACPI_HEST_NOTIFY_GPIO: 1158 mutex_lock(&ghes_list_mutex); 1159 list_del_rcu(&ghes->list); 1160 if (list_empty(&ghes_hed)) 1161 unregister_acpi_hed_notifier(&ghes_notifier_hed); 1162 mutex_unlock(&ghes_list_mutex); 1163 synchronize_rcu(); 1164 break; 1165 1166 case ACPI_HEST_NOTIFY_SEA: 1167 ghes_sea_remove(ghes); 1168 break; 1169 case ACPI_HEST_NOTIFY_NMI: 1170 ghes_nmi_remove(ghes); 1171 break; 1172 default: 1173 BUG(); 1174 break; 1175 } 1176 1177 ghes_fini(ghes); 1178 1179 ghes_edac_unregister(ghes); 1180 1181 kfree(ghes); 1182 1183 platform_set_drvdata(ghes_dev, NULL); 1184 1185 return 0; 1186 } 1187 1188 static struct platform_driver ghes_platform_driver = { 1189 .driver = { 1190 .name = "GHES", 1191 }, 1192 .probe = ghes_probe, 1193 .remove = ghes_remove, 1194 }; 1195 1196 static int __init ghes_init(void) 1197 { 1198 int rc; 1199 1200 if (acpi_disabled) 1201 return -ENODEV; 1202 1203 switch (hest_disable) { 1204 case HEST_NOT_FOUND: 1205 return -ENODEV; 1206 case HEST_DISABLED: 1207 pr_info(GHES_PFX "HEST is not enabled!\n"); 1208 return -EINVAL; 1209 default: 1210 break; 1211 } 1212 1213 if (ghes_disable) { 1214 pr_info(GHES_PFX "GHES is not enabled!\n"); 1215 return -EINVAL; 1216 } 1217 1218 ghes_nmi_init_cxt(); 1219 1220 rc = ghes_estatus_pool_init(); 1221 if (rc) 1222 goto err; 1223 1224 rc = ghes_estatus_pool_expand(GHES_ESTATUS_CACHE_AVG_SIZE * 1225 GHES_ESTATUS_CACHE_ALLOCED_MAX); 1226 if (rc) 1227 goto err_pool_exit; 1228 1229 rc = platform_driver_register(&ghes_platform_driver); 1230 if (rc) 1231 goto err_pool_exit; 1232 1233 rc = apei_osc_setup(); 1234 if (rc == 0 && osc_sb_apei_support_acked) 1235 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n"); 1236 else if (rc == 0 && !osc_sb_apei_support_acked) 1237 pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n"); 1238 else if (rc && osc_sb_apei_support_acked) 1239 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n"); 1240 else 1241 pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n"); 1242 1243 return 0; 1244 err_pool_exit: 1245 ghes_estatus_pool_exit(); 1246 err: 1247 return rc; 1248 } 1249 device_initcall(ghes_init); 1250