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/module.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 bool ghes_disable; 83 module_param_named(disable, ghes_disable, bool, 0); 84 85 /* 86 * All error sources notified with SCI shares one notifier function, 87 * so they need to be linked and checked one by one. This is applied 88 * to NMI too. 89 * 90 * RCU is used for these lists, so ghes_list_mutex is only used for 91 * list changing, not for traversing. 92 */ 93 static LIST_HEAD(ghes_sci); 94 static DEFINE_MUTEX(ghes_list_mutex); 95 96 /* 97 * Because the memory area used to transfer hardware error information 98 * from BIOS to Linux can be determined only in NMI, IRQ or timer 99 * handler, but general ioremap can not be used in atomic context, so 100 * a special version of atomic ioremap is implemented for that. 101 */ 102 103 /* 104 * Two virtual pages are used, one for IRQ/PROCESS context, the other for 105 * NMI context (optionally). 106 */ 107 #ifdef CONFIG_HAVE_ACPI_APEI_NMI 108 #define GHES_IOREMAP_PAGES 2 109 #else 110 #define GHES_IOREMAP_PAGES 1 111 #endif 112 #define GHES_IOREMAP_IRQ_PAGE(base) (base) 113 #define GHES_IOREMAP_NMI_PAGE(base) ((base) + PAGE_SIZE) 114 115 /* virtual memory area for atomic ioremap */ 116 static struct vm_struct *ghes_ioremap_area; 117 /* 118 * These 2 spinlock is used to prevent atomic ioremap virtual memory 119 * area from being mapped 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_ioremap_init(void) 131 { 132 ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES, 133 VM_IOREMAP, VMALLOC_START, VMALLOC_END); 134 if (!ghes_ioremap_area) { 135 pr_err(GHES_PFX "Failed to allocate virtual memory area for atomic ioremap.\n"); 136 return -ENOMEM; 137 } 138 139 return 0; 140 } 141 142 static void ghes_ioremap_exit(void) 143 { 144 free_vm_area(ghes_ioremap_area); 145 } 146 147 static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn) 148 { 149 unsigned long vaddr; 150 151 vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr); 152 ioremap_page_range(vaddr, vaddr + PAGE_SIZE, 153 pfn << PAGE_SHIFT, PAGE_KERNEL); 154 155 return (void __iomem *)vaddr; 156 } 157 158 static void __iomem *ghes_ioremap_pfn_irq(u64 pfn) 159 { 160 unsigned long vaddr; 161 162 vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr); 163 ioremap_page_range(vaddr, vaddr + PAGE_SIZE, 164 pfn << PAGE_SHIFT, PAGE_KERNEL); 165 166 return (void __iomem *)vaddr; 167 } 168 169 static void ghes_iounmap_nmi(void __iomem *vaddr_ptr) 170 { 171 unsigned long vaddr = (unsigned long __force)vaddr_ptr; 172 void *base = ghes_ioremap_area->addr; 173 174 BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base)); 175 unmap_kernel_range_noflush(vaddr, PAGE_SIZE); 176 arch_apei_flush_tlb_one(vaddr); 177 } 178 179 static void ghes_iounmap_irq(void __iomem *vaddr_ptr) 180 { 181 unsigned long vaddr = (unsigned long __force)vaddr_ptr; 182 void *base = ghes_ioremap_area->addr; 183 184 BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base)); 185 unmap_kernel_range_noflush(vaddr, PAGE_SIZE); 186 arch_apei_flush_tlb_one(vaddr); 187 } 188 189 static int ghes_estatus_pool_init(void) 190 { 191 ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1); 192 if (!ghes_estatus_pool) 193 return -ENOMEM; 194 return 0; 195 } 196 197 static void ghes_estatus_pool_free_chunk_page(struct gen_pool *pool, 198 struct gen_pool_chunk *chunk, 199 void *data) 200 { 201 free_page(chunk->start_addr); 202 } 203 204 static void ghes_estatus_pool_exit(void) 205 { 206 gen_pool_for_each_chunk(ghes_estatus_pool, 207 ghes_estatus_pool_free_chunk_page, NULL); 208 gen_pool_destroy(ghes_estatus_pool); 209 } 210 211 static int ghes_estatus_pool_expand(unsigned long len) 212 { 213 unsigned long i, pages, size, addr; 214 int ret; 215 216 ghes_estatus_pool_size_request += PAGE_ALIGN(len); 217 size = gen_pool_size(ghes_estatus_pool); 218 if (size >= ghes_estatus_pool_size_request) 219 return 0; 220 pages = (ghes_estatus_pool_size_request - size) / PAGE_SIZE; 221 for (i = 0; i < pages; i++) { 222 addr = __get_free_page(GFP_KERNEL); 223 if (!addr) 224 return -ENOMEM; 225 ret = gen_pool_add(ghes_estatus_pool, addr, PAGE_SIZE, -1); 226 if (ret) 227 return ret; 228 } 229 230 return 0; 231 } 232 233 static struct ghes *ghes_new(struct acpi_hest_generic *generic) 234 { 235 struct ghes *ghes; 236 unsigned int error_block_length; 237 int rc; 238 239 ghes = kzalloc(sizeof(*ghes), GFP_KERNEL); 240 if (!ghes) 241 return ERR_PTR(-ENOMEM); 242 ghes->generic = generic; 243 rc = apei_map_generic_address(&generic->error_status_address); 244 if (rc) 245 goto err_free; 246 error_block_length = generic->error_block_length; 247 if (error_block_length > GHES_ESTATUS_MAX_SIZE) { 248 pr_warning(FW_WARN GHES_PFX 249 "Error status block length is too long: %u for " 250 "generic hardware error source: %d.\n", 251 error_block_length, generic->header.source_id); 252 error_block_length = GHES_ESTATUS_MAX_SIZE; 253 } 254 ghes->estatus = kmalloc(error_block_length, GFP_KERNEL); 255 if (!ghes->estatus) { 256 rc = -ENOMEM; 257 goto err_unmap; 258 } 259 260 return ghes; 261 262 err_unmap: 263 apei_unmap_generic_address(&generic->error_status_address); 264 err_free: 265 kfree(ghes); 266 return ERR_PTR(rc); 267 } 268 269 static void ghes_fini(struct ghes *ghes) 270 { 271 kfree(ghes->estatus); 272 apei_unmap_generic_address(&ghes->generic->error_status_address); 273 } 274 275 static inline int ghes_severity(int severity) 276 { 277 switch (severity) { 278 case CPER_SEV_INFORMATIONAL: 279 return GHES_SEV_NO; 280 case CPER_SEV_CORRECTED: 281 return GHES_SEV_CORRECTED; 282 case CPER_SEV_RECOVERABLE: 283 return GHES_SEV_RECOVERABLE; 284 case CPER_SEV_FATAL: 285 return GHES_SEV_PANIC; 286 default: 287 /* Unknown, go panic */ 288 return GHES_SEV_PANIC; 289 } 290 } 291 292 static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, 293 int from_phys) 294 { 295 void __iomem *vaddr; 296 unsigned long flags = 0; 297 int in_nmi = in_nmi(); 298 u64 offset; 299 u32 trunk; 300 301 while (len > 0) { 302 offset = paddr - (paddr & PAGE_MASK); 303 if (in_nmi) { 304 raw_spin_lock(&ghes_ioremap_lock_nmi); 305 vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT); 306 } else { 307 spin_lock_irqsave(&ghes_ioremap_lock_irq, flags); 308 vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT); 309 } 310 trunk = PAGE_SIZE - offset; 311 trunk = min(trunk, len); 312 if (from_phys) 313 memcpy_fromio(buffer, vaddr + offset, trunk); 314 else 315 memcpy_toio(vaddr + offset, buffer, trunk); 316 len -= trunk; 317 paddr += trunk; 318 buffer += trunk; 319 if (in_nmi) { 320 ghes_iounmap_nmi(vaddr); 321 raw_spin_unlock(&ghes_ioremap_lock_nmi); 322 } else { 323 ghes_iounmap_irq(vaddr); 324 spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags); 325 } 326 } 327 } 328 329 static int ghes_read_estatus(struct ghes *ghes, int silent) 330 { 331 struct acpi_hest_generic *g = ghes->generic; 332 u64 buf_paddr; 333 u32 len; 334 int rc; 335 336 rc = apei_read(&buf_paddr, &g->error_status_address); 337 if (rc) { 338 if (!silent && printk_ratelimit()) 339 pr_warning(FW_WARN GHES_PFX 340 "Failed to read error status block address for hardware error source: %d.\n", 341 g->header.source_id); 342 return -EIO; 343 } 344 if (!buf_paddr) 345 return -ENOENT; 346 347 ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, 348 sizeof(*ghes->estatus), 1); 349 if (!ghes->estatus->block_status) 350 return -ENOENT; 351 352 ghes->buffer_paddr = buf_paddr; 353 ghes->flags |= GHES_TO_CLEAR; 354 355 rc = -EIO; 356 len = cper_estatus_len(ghes->estatus); 357 if (len < sizeof(*ghes->estatus)) 358 goto err_read_block; 359 if (len > ghes->generic->error_block_length) 360 goto err_read_block; 361 if (cper_estatus_check_header(ghes->estatus)) 362 goto err_read_block; 363 ghes_copy_tofrom_phys(ghes->estatus + 1, 364 buf_paddr + sizeof(*ghes->estatus), 365 len - sizeof(*ghes->estatus), 1); 366 if (cper_estatus_check(ghes->estatus)) 367 goto err_read_block; 368 rc = 0; 369 370 err_read_block: 371 if (rc && !silent && printk_ratelimit()) 372 pr_warning(FW_WARN GHES_PFX 373 "Failed to read error status block!\n"); 374 return rc; 375 } 376 377 static void ghes_clear_estatus(struct ghes *ghes) 378 { 379 ghes->estatus->block_status = 0; 380 if (!(ghes->flags & GHES_TO_CLEAR)) 381 return; 382 ghes_copy_tofrom_phys(ghes->estatus, ghes->buffer_paddr, 383 sizeof(ghes->estatus->block_status), 0); 384 ghes->flags &= ~GHES_TO_CLEAR; 385 } 386 387 static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int sev) 388 { 389 #ifdef CONFIG_ACPI_APEI_MEMORY_FAILURE 390 unsigned long pfn; 391 int flags = -1; 392 int sec_sev = ghes_severity(gdata->error_severity); 393 struct cper_sec_mem_err *mem_err; 394 mem_err = (struct cper_sec_mem_err *)(gdata + 1); 395 396 if (!(mem_err->validation_bits & CPER_MEM_VALID_PA)) 397 return; 398 399 pfn = mem_err->physical_addr >> PAGE_SHIFT; 400 if (!pfn_valid(pfn)) { 401 pr_warn_ratelimited(FW_WARN GHES_PFX 402 "Invalid address in generic error data: %#llx\n", 403 mem_err->physical_addr); 404 return; 405 } 406 407 /* iff following two events can be handled properly by now */ 408 if (sec_sev == GHES_SEV_CORRECTED && 409 (gdata->flags & CPER_SEC_ERROR_THRESHOLD_EXCEEDED)) 410 flags = MF_SOFT_OFFLINE; 411 if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE) 412 flags = 0; 413 414 if (flags != -1) 415 memory_failure_queue(pfn, 0, flags); 416 #endif 417 } 418 419 static void ghes_do_proc(struct ghes *ghes, 420 const struct acpi_hest_generic_status *estatus) 421 { 422 int sev, sec_sev; 423 struct acpi_hest_generic_data *gdata; 424 425 sev = ghes_severity(estatus->error_severity); 426 apei_estatus_for_each_section(estatus, gdata) { 427 sec_sev = ghes_severity(gdata->error_severity); 428 if (!uuid_le_cmp(*(uuid_le *)gdata->section_type, 429 CPER_SEC_PLATFORM_MEM)) { 430 struct cper_sec_mem_err *mem_err; 431 mem_err = (struct cper_sec_mem_err *)(gdata+1); 432 ghes_edac_report_mem_error(ghes, sev, mem_err); 433 434 arch_apei_report_mem_error(sev, mem_err); 435 ghes_handle_memory_failure(gdata, sev); 436 } 437 #ifdef CONFIG_ACPI_APEI_PCIEAER 438 else if (!uuid_le_cmp(*(uuid_le *)gdata->section_type, 439 CPER_SEC_PCIE)) { 440 struct cper_sec_pcie *pcie_err; 441 pcie_err = (struct cper_sec_pcie *)(gdata+1); 442 if (sev == GHES_SEV_RECOVERABLE && 443 sec_sev == GHES_SEV_RECOVERABLE && 444 pcie_err->validation_bits & CPER_PCIE_VALID_DEVICE_ID && 445 pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) { 446 unsigned int devfn; 447 int aer_severity; 448 449 devfn = PCI_DEVFN(pcie_err->device_id.device, 450 pcie_err->device_id.function); 451 aer_severity = cper_severity_to_aer(sev); 452 453 /* 454 * If firmware reset the component to contain 455 * the error, we must reinitialize it before 456 * use, so treat it as a fatal AER error. 457 */ 458 if (gdata->flags & CPER_SEC_RESET) 459 aer_severity = AER_FATAL; 460 461 aer_recover_queue(pcie_err->device_id.segment, 462 pcie_err->device_id.bus, 463 devfn, aer_severity, 464 (struct aer_capability_regs *) 465 pcie_err->aer_info); 466 } 467 468 } 469 #endif 470 } 471 } 472 473 static void __ghes_print_estatus(const char *pfx, 474 const struct acpi_hest_generic *generic, 475 const struct acpi_hest_generic_status *estatus) 476 { 477 static atomic_t seqno; 478 unsigned int curr_seqno; 479 char pfx_seq[64]; 480 481 if (pfx == NULL) { 482 if (ghes_severity(estatus->error_severity) <= 483 GHES_SEV_CORRECTED) 484 pfx = KERN_WARNING; 485 else 486 pfx = KERN_ERR; 487 } 488 curr_seqno = atomic_inc_return(&seqno); 489 snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}" HW_ERR, pfx, curr_seqno); 490 printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n", 491 pfx_seq, generic->header.source_id); 492 cper_estatus_print(pfx_seq, estatus); 493 } 494 495 static int ghes_print_estatus(const char *pfx, 496 const struct acpi_hest_generic *generic, 497 const struct acpi_hest_generic_status *estatus) 498 { 499 /* Not more than 2 messages every 5 seconds */ 500 static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2); 501 static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2); 502 struct ratelimit_state *ratelimit; 503 504 if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED) 505 ratelimit = &ratelimit_corrected; 506 else 507 ratelimit = &ratelimit_uncorrected; 508 if (__ratelimit(ratelimit)) { 509 __ghes_print_estatus(pfx, generic, estatus); 510 return 1; 511 } 512 return 0; 513 } 514 515 /* 516 * GHES error status reporting throttle, to report more kinds of 517 * errors, instead of just most frequently occurred errors. 518 */ 519 static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus) 520 { 521 u32 len; 522 int i, cached = 0; 523 unsigned long long now; 524 struct ghes_estatus_cache *cache; 525 struct acpi_hest_generic_status *cache_estatus; 526 527 len = cper_estatus_len(estatus); 528 rcu_read_lock(); 529 for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { 530 cache = rcu_dereference(ghes_estatus_caches[i]); 531 if (cache == NULL) 532 continue; 533 if (len != cache->estatus_len) 534 continue; 535 cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); 536 if (memcmp(estatus, cache_estatus, len)) 537 continue; 538 atomic_inc(&cache->count); 539 now = sched_clock(); 540 if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC) 541 cached = 1; 542 break; 543 } 544 rcu_read_unlock(); 545 return cached; 546 } 547 548 static struct ghes_estatus_cache *ghes_estatus_cache_alloc( 549 struct acpi_hest_generic *generic, 550 struct acpi_hest_generic_status *estatus) 551 { 552 int alloced; 553 u32 len, cache_len; 554 struct ghes_estatus_cache *cache; 555 struct acpi_hest_generic_status *cache_estatus; 556 557 alloced = atomic_add_return(1, &ghes_estatus_cache_alloced); 558 if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) { 559 atomic_dec(&ghes_estatus_cache_alloced); 560 return NULL; 561 } 562 len = cper_estatus_len(estatus); 563 cache_len = GHES_ESTATUS_CACHE_LEN(len); 564 cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len); 565 if (!cache) { 566 atomic_dec(&ghes_estatus_cache_alloced); 567 return NULL; 568 } 569 cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); 570 memcpy(cache_estatus, estatus, len); 571 cache->estatus_len = len; 572 atomic_set(&cache->count, 0); 573 cache->generic = generic; 574 cache->time_in = sched_clock(); 575 return cache; 576 } 577 578 static void ghes_estatus_cache_free(struct ghes_estatus_cache *cache) 579 { 580 u32 len; 581 582 len = cper_estatus_len(GHES_ESTATUS_FROM_CACHE(cache)); 583 len = GHES_ESTATUS_CACHE_LEN(len); 584 gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len); 585 atomic_dec(&ghes_estatus_cache_alloced); 586 } 587 588 static void ghes_estatus_cache_rcu_free(struct rcu_head *head) 589 { 590 struct ghes_estatus_cache *cache; 591 592 cache = container_of(head, struct ghes_estatus_cache, rcu); 593 ghes_estatus_cache_free(cache); 594 } 595 596 static void ghes_estatus_cache_add( 597 struct acpi_hest_generic *generic, 598 struct acpi_hest_generic_status *estatus) 599 { 600 int i, slot = -1, count; 601 unsigned long long now, duration, period, max_period = 0; 602 struct ghes_estatus_cache *cache, *slot_cache = NULL, *new_cache; 603 604 new_cache = ghes_estatus_cache_alloc(generic, estatus); 605 if (new_cache == NULL) 606 return; 607 rcu_read_lock(); 608 now = sched_clock(); 609 for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { 610 cache = rcu_dereference(ghes_estatus_caches[i]); 611 if (cache == NULL) { 612 slot = i; 613 slot_cache = NULL; 614 break; 615 } 616 duration = now - cache->time_in; 617 if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) { 618 slot = i; 619 slot_cache = cache; 620 break; 621 } 622 count = atomic_read(&cache->count); 623 period = duration; 624 do_div(period, (count + 1)); 625 if (period > max_period) { 626 max_period = period; 627 slot = i; 628 slot_cache = cache; 629 } 630 } 631 /* new_cache must be put into array after its contents are written */ 632 smp_wmb(); 633 if (slot != -1 && cmpxchg(ghes_estatus_caches + slot, 634 slot_cache, new_cache) == slot_cache) { 635 if (slot_cache) 636 call_rcu(&slot_cache->rcu, ghes_estatus_cache_rcu_free); 637 } else 638 ghes_estatus_cache_free(new_cache); 639 rcu_read_unlock(); 640 } 641 642 static int ghes_proc(struct ghes *ghes) 643 { 644 int rc; 645 646 rc = ghes_read_estatus(ghes, 0); 647 if (rc) 648 goto out; 649 if (!ghes_estatus_cached(ghes->estatus)) { 650 if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) 651 ghes_estatus_cache_add(ghes->generic, ghes->estatus); 652 } 653 ghes_do_proc(ghes, ghes->estatus); 654 out: 655 ghes_clear_estatus(ghes); 656 return 0; 657 } 658 659 static void ghes_add_timer(struct ghes *ghes) 660 { 661 struct acpi_hest_generic *g = ghes->generic; 662 unsigned long expire; 663 664 if (!g->notify.poll_interval) { 665 pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n", 666 g->header.source_id); 667 return; 668 } 669 expire = jiffies + msecs_to_jiffies(g->notify.poll_interval); 670 ghes->timer.expires = round_jiffies_relative(expire); 671 add_timer(&ghes->timer); 672 } 673 674 static void ghes_poll_func(unsigned long data) 675 { 676 struct ghes *ghes = (void *)data; 677 678 ghes_proc(ghes); 679 if (!(ghes->flags & GHES_EXITING)) 680 ghes_add_timer(ghes); 681 } 682 683 static irqreturn_t ghes_irq_func(int irq, void *data) 684 { 685 struct ghes *ghes = data; 686 int rc; 687 688 rc = ghes_proc(ghes); 689 if (rc) 690 return IRQ_NONE; 691 692 return IRQ_HANDLED; 693 } 694 695 static int ghes_notify_sci(struct notifier_block *this, 696 unsigned long event, void *data) 697 { 698 struct ghes *ghes; 699 int ret = NOTIFY_DONE; 700 701 rcu_read_lock(); 702 list_for_each_entry_rcu(ghes, &ghes_sci, list) { 703 if (!ghes_proc(ghes)) 704 ret = NOTIFY_OK; 705 } 706 rcu_read_unlock(); 707 708 return ret; 709 } 710 711 static struct notifier_block ghes_notifier_sci = { 712 .notifier_call = ghes_notify_sci, 713 }; 714 715 #ifdef CONFIG_HAVE_ACPI_APEI_NMI 716 /* 717 * printk is not safe in NMI context. So in NMI handler, we allocate 718 * required memory from lock-less memory allocator 719 * (ghes_estatus_pool), save estatus into it, put them into lock-less 720 * list (ghes_estatus_llist), then delay printk into IRQ context via 721 * irq_work (ghes_proc_irq_work). ghes_estatus_size_request record 722 * required pool size by all NMI error source. 723 */ 724 static struct llist_head ghes_estatus_llist; 725 static struct irq_work ghes_proc_irq_work; 726 727 /* 728 * NMI may be triggered on any CPU, so ghes_in_nmi is used for 729 * having only one concurrent reader. 730 */ 731 static atomic_t ghes_in_nmi = ATOMIC_INIT(0); 732 733 static LIST_HEAD(ghes_nmi); 734 735 static int ghes_panic_timeout __read_mostly = 30; 736 737 static void ghes_proc_in_irq(struct irq_work *irq_work) 738 { 739 struct llist_node *llnode, *next; 740 struct ghes_estatus_node *estatus_node; 741 struct acpi_hest_generic *generic; 742 struct acpi_hest_generic_status *estatus; 743 u32 len, node_len; 744 745 llnode = llist_del_all(&ghes_estatus_llist); 746 /* 747 * Because the time order of estatus in list is reversed, 748 * revert it back to proper order. 749 */ 750 llnode = llist_reverse_order(llnode); 751 while (llnode) { 752 next = llnode->next; 753 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 754 llnode); 755 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 756 len = cper_estatus_len(estatus); 757 node_len = GHES_ESTATUS_NODE_LEN(len); 758 ghes_do_proc(estatus_node->ghes, estatus); 759 if (!ghes_estatus_cached(estatus)) { 760 generic = estatus_node->generic; 761 if (ghes_print_estatus(NULL, generic, estatus)) 762 ghes_estatus_cache_add(generic, estatus); 763 } 764 gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, 765 node_len); 766 llnode = next; 767 } 768 } 769 770 static void ghes_print_queued_estatus(void) 771 { 772 struct llist_node *llnode; 773 struct ghes_estatus_node *estatus_node; 774 struct acpi_hest_generic *generic; 775 struct acpi_hest_generic_status *estatus; 776 u32 len, node_len; 777 778 llnode = llist_del_all(&ghes_estatus_llist); 779 /* 780 * Because the time order of estatus in list is reversed, 781 * revert it back to proper order. 782 */ 783 llnode = llist_reverse_order(llnode); 784 while (llnode) { 785 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 786 llnode); 787 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 788 len = cper_estatus_len(estatus); 789 node_len = GHES_ESTATUS_NODE_LEN(len); 790 generic = estatus_node->generic; 791 ghes_print_estatus(NULL, generic, estatus); 792 llnode = llnode->next; 793 } 794 } 795 796 /* Save estatus for further processing in IRQ context */ 797 static void __process_error(struct ghes *ghes) 798 { 799 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 800 u32 len, node_len; 801 struct ghes_estatus_node *estatus_node; 802 struct acpi_hest_generic_status *estatus; 803 804 if (ghes_estatus_cached(ghes->estatus)) 805 return; 806 807 len = cper_estatus_len(ghes->estatus); 808 node_len = GHES_ESTATUS_NODE_LEN(len); 809 810 estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); 811 if (!estatus_node) 812 return; 813 814 estatus_node->ghes = ghes; 815 estatus_node->generic = ghes->generic; 816 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 817 memcpy(estatus, ghes->estatus, len); 818 llist_add(&estatus_node->llnode, &ghes_estatus_llist); 819 #endif 820 } 821 822 static void __ghes_panic(struct ghes *ghes) 823 { 824 oops_begin(); 825 ghes_print_queued_estatus(); 826 __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); 827 828 /* reboot to log the error! */ 829 if (panic_timeout == 0) 830 panic_timeout = ghes_panic_timeout; 831 panic("Fatal hardware error!"); 832 } 833 834 static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) 835 { 836 struct ghes *ghes; 837 int sev, ret = NMI_DONE; 838 839 if (!atomic_add_unless(&ghes_in_nmi, 1, 1)) 840 return ret; 841 842 list_for_each_entry_rcu(ghes, &ghes_nmi, list) { 843 if (ghes_read_estatus(ghes, 1)) { 844 ghes_clear_estatus(ghes); 845 continue; 846 } 847 848 sev = ghes_severity(ghes->estatus->error_severity); 849 if (sev >= GHES_SEV_PANIC) 850 __ghes_panic(ghes); 851 852 if (!(ghes->flags & GHES_TO_CLEAR)) 853 continue; 854 855 __process_error(ghes); 856 ghes_clear_estatus(ghes); 857 858 ret = NMI_HANDLED; 859 } 860 861 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 862 irq_work_queue(&ghes_proc_irq_work); 863 #endif 864 atomic_dec(&ghes_in_nmi); 865 return ret; 866 } 867 868 static unsigned long ghes_esource_prealloc_size( 869 const struct acpi_hest_generic *generic) 870 { 871 unsigned long block_length, prealloc_records, prealloc_size; 872 873 block_length = min_t(unsigned long, generic->error_block_length, 874 GHES_ESTATUS_MAX_SIZE); 875 prealloc_records = max_t(unsigned long, 876 generic->records_to_preallocate, 1); 877 prealloc_size = min_t(unsigned long, block_length * prealloc_records, 878 GHES_ESOURCE_PREALLOC_MAX_SIZE); 879 880 return prealloc_size; 881 } 882 883 static void ghes_estatus_pool_shrink(unsigned long len) 884 { 885 ghes_estatus_pool_size_request -= PAGE_ALIGN(len); 886 } 887 888 static void ghes_nmi_add(struct ghes *ghes) 889 { 890 unsigned long len; 891 892 len = ghes_esource_prealloc_size(ghes->generic); 893 ghes_estatus_pool_expand(len); 894 mutex_lock(&ghes_list_mutex); 895 if (list_empty(&ghes_nmi)) 896 register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes"); 897 list_add_rcu(&ghes->list, &ghes_nmi); 898 mutex_unlock(&ghes_list_mutex); 899 } 900 901 static void ghes_nmi_remove(struct ghes *ghes) 902 { 903 unsigned long len; 904 905 mutex_lock(&ghes_list_mutex); 906 list_del_rcu(&ghes->list); 907 if (list_empty(&ghes_nmi)) 908 unregister_nmi_handler(NMI_LOCAL, "ghes"); 909 mutex_unlock(&ghes_list_mutex); 910 /* 911 * To synchronize with NMI handler, ghes can only be 912 * freed after NMI handler finishes. 913 */ 914 synchronize_rcu(); 915 len = ghes_esource_prealloc_size(ghes->generic); 916 ghes_estatus_pool_shrink(len); 917 } 918 919 static void ghes_nmi_init_cxt(void) 920 { 921 init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq); 922 } 923 #else /* CONFIG_HAVE_ACPI_APEI_NMI */ 924 static inline void ghes_nmi_add(struct ghes *ghes) 925 { 926 pr_err(GHES_PFX "ID: %d, trying to add NMI notification which is not supported!\n", 927 ghes->generic->header.source_id); 928 BUG(); 929 } 930 931 static inline void ghes_nmi_remove(struct ghes *ghes) 932 { 933 pr_err(GHES_PFX "ID: %d, trying to remove NMI notification which is not supported!\n", 934 ghes->generic->header.source_id); 935 BUG(); 936 } 937 938 static inline void ghes_nmi_init_cxt(void) 939 { 940 } 941 #endif /* CONFIG_HAVE_ACPI_APEI_NMI */ 942 943 static int ghes_probe(struct platform_device *ghes_dev) 944 { 945 struct acpi_hest_generic *generic; 946 struct ghes *ghes = NULL; 947 948 int rc = -EINVAL; 949 950 generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data; 951 if (!generic->enabled) 952 return -ENODEV; 953 954 switch (generic->notify.type) { 955 case ACPI_HEST_NOTIFY_POLLED: 956 case ACPI_HEST_NOTIFY_EXTERNAL: 957 case ACPI_HEST_NOTIFY_SCI: 958 break; 959 case ACPI_HEST_NOTIFY_NMI: 960 if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) { 961 pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n", 962 generic->header.source_id); 963 goto err; 964 } 965 break; 966 case ACPI_HEST_NOTIFY_LOCAL: 967 pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n", 968 generic->header.source_id); 969 goto err; 970 default: 971 pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n", 972 generic->notify.type, generic->header.source_id); 973 goto err; 974 } 975 976 rc = -EIO; 977 if (generic->error_block_length < 978 sizeof(struct acpi_hest_generic_status)) { 979 pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n", 980 generic->error_block_length, 981 generic->header.source_id); 982 goto err; 983 } 984 ghes = ghes_new(generic); 985 if (IS_ERR(ghes)) { 986 rc = PTR_ERR(ghes); 987 ghes = NULL; 988 goto err; 989 } 990 991 rc = ghes_edac_register(ghes, &ghes_dev->dev); 992 if (rc < 0) 993 goto err; 994 995 switch (generic->notify.type) { 996 case ACPI_HEST_NOTIFY_POLLED: 997 ghes->timer.function = ghes_poll_func; 998 ghes->timer.data = (unsigned long)ghes; 999 init_timer_deferrable(&ghes->timer); 1000 ghes_add_timer(ghes); 1001 break; 1002 case ACPI_HEST_NOTIFY_EXTERNAL: 1003 /* External interrupt vector is GSI */ 1004 rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq); 1005 if (rc) { 1006 pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n", 1007 generic->header.source_id); 1008 goto err_edac_unreg; 1009 } 1010 rc = request_irq(ghes->irq, ghes_irq_func, 0, "GHES IRQ", ghes); 1011 if (rc) { 1012 pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n", 1013 generic->header.source_id); 1014 goto err_edac_unreg; 1015 } 1016 break; 1017 case ACPI_HEST_NOTIFY_SCI: 1018 mutex_lock(&ghes_list_mutex); 1019 if (list_empty(&ghes_sci)) 1020 register_acpi_hed_notifier(&ghes_notifier_sci); 1021 list_add_rcu(&ghes->list, &ghes_sci); 1022 mutex_unlock(&ghes_list_mutex); 1023 break; 1024 case ACPI_HEST_NOTIFY_NMI: 1025 ghes_nmi_add(ghes); 1026 break; 1027 default: 1028 BUG(); 1029 } 1030 platform_set_drvdata(ghes_dev, ghes); 1031 1032 return 0; 1033 err_edac_unreg: 1034 ghes_edac_unregister(ghes); 1035 err: 1036 if (ghes) { 1037 ghes_fini(ghes); 1038 kfree(ghes); 1039 } 1040 return rc; 1041 } 1042 1043 static int ghes_remove(struct platform_device *ghes_dev) 1044 { 1045 struct ghes *ghes; 1046 struct acpi_hest_generic *generic; 1047 1048 ghes = platform_get_drvdata(ghes_dev); 1049 generic = ghes->generic; 1050 1051 ghes->flags |= GHES_EXITING; 1052 switch (generic->notify.type) { 1053 case ACPI_HEST_NOTIFY_POLLED: 1054 del_timer_sync(&ghes->timer); 1055 break; 1056 case ACPI_HEST_NOTIFY_EXTERNAL: 1057 free_irq(ghes->irq, ghes); 1058 break; 1059 case ACPI_HEST_NOTIFY_SCI: 1060 mutex_lock(&ghes_list_mutex); 1061 list_del_rcu(&ghes->list); 1062 if (list_empty(&ghes_sci)) 1063 unregister_acpi_hed_notifier(&ghes_notifier_sci); 1064 mutex_unlock(&ghes_list_mutex); 1065 break; 1066 case ACPI_HEST_NOTIFY_NMI: 1067 ghes_nmi_remove(ghes); 1068 break; 1069 default: 1070 BUG(); 1071 break; 1072 } 1073 1074 ghes_fini(ghes); 1075 1076 ghes_edac_unregister(ghes); 1077 1078 kfree(ghes); 1079 1080 platform_set_drvdata(ghes_dev, NULL); 1081 1082 return 0; 1083 } 1084 1085 static struct platform_driver ghes_platform_driver = { 1086 .driver = { 1087 .name = "GHES", 1088 }, 1089 .probe = ghes_probe, 1090 .remove = ghes_remove, 1091 }; 1092 1093 static int __init ghes_init(void) 1094 { 1095 int rc; 1096 1097 if (acpi_disabled) 1098 return -ENODEV; 1099 1100 if (hest_disable) { 1101 pr_info(GHES_PFX "HEST is not enabled!\n"); 1102 return -EINVAL; 1103 } 1104 1105 if (ghes_disable) { 1106 pr_info(GHES_PFX "GHES is not enabled!\n"); 1107 return -EINVAL; 1108 } 1109 1110 ghes_nmi_init_cxt(); 1111 1112 rc = ghes_ioremap_init(); 1113 if (rc) 1114 goto err; 1115 1116 rc = ghes_estatus_pool_init(); 1117 if (rc) 1118 goto err_ioremap_exit; 1119 1120 rc = ghes_estatus_pool_expand(GHES_ESTATUS_CACHE_AVG_SIZE * 1121 GHES_ESTATUS_CACHE_ALLOCED_MAX); 1122 if (rc) 1123 goto err_pool_exit; 1124 1125 rc = platform_driver_register(&ghes_platform_driver); 1126 if (rc) 1127 goto err_pool_exit; 1128 1129 rc = apei_osc_setup(); 1130 if (rc == 0 && osc_sb_apei_support_acked) 1131 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n"); 1132 else if (rc == 0 && !osc_sb_apei_support_acked) 1133 pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n"); 1134 else if (rc && osc_sb_apei_support_acked) 1135 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n"); 1136 else 1137 pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n"); 1138 1139 return 0; 1140 err_pool_exit: 1141 ghes_estatus_pool_exit(); 1142 err_ioremap_exit: 1143 ghes_ioremap_exit(); 1144 err: 1145 return rc; 1146 } 1147 1148 static void __exit ghes_exit(void) 1149 { 1150 platform_driver_unregister(&ghes_platform_driver); 1151 ghes_estatus_pool_exit(); 1152 ghes_ioremap_exit(); 1153 } 1154 1155 module_init(ghes_init); 1156 module_exit(ghes_exit); 1157 1158 MODULE_AUTHOR("Huang Ying"); 1159 MODULE_DESCRIPTION("APEI Generic Hardware Error Source support"); 1160 MODULE_LICENSE("GPL"); 1161 MODULE_ALIAS("platform:GHES"); 1162