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