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 * You should have received a copy of the GNU General Public License 28 * along with this program; if not, write to the Free Software 29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 30 */ 31 32 #include <linux/kernel.h> 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/acpi.h> 36 #include <linux/io.h> 37 #include <linux/interrupt.h> 38 #include <linux/timer.h> 39 #include <linux/cper.h> 40 #include <linux/kdebug.h> 41 #include <linux/platform_device.h> 42 #include <linux/mutex.h> 43 #include <linux/ratelimit.h> 44 #include <linux/vmalloc.h> 45 #include <linux/irq_work.h> 46 #include <linux/llist.h> 47 #include <linux/genalloc.h> 48 #include <linux/pci.h> 49 #include <linux/aer.h> 50 #include <linux/nmi.h> 51 52 #include <acpi/ghes.h> 53 #include <acpi/apei.h> 54 #include <asm/tlbflush.h> 55 56 #include "apei-internal.h" 57 58 #define GHES_PFX "GHES: " 59 60 #define GHES_ESTATUS_MAX_SIZE 65536 61 #define GHES_ESOURCE_PREALLOC_MAX_SIZE 65536 62 63 #define GHES_ESTATUS_POOL_MIN_ALLOC_ORDER 3 64 65 /* This is just an estimation for memory pool allocation */ 66 #define GHES_ESTATUS_CACHE_AVG_SIZE 512 67 68 #define GHES_ESTATUS_CACHES_SIZE 4 69 70 #define GHES_ESTATUS_IN_CACHE_MAX_NSEC 10000000000ULL 71 /* Prevent too many caches are allocated because of RCU */ 72 #define GHES_ESTATUS_CACHE_ALLOCED_MAX (GHES_ESTATUS_CACHES_SIZE * 3 / 2) 73 74 #define GHES_ESTATUS_CACHE_LEN(estatus_len) \ 75 (sizeof(struct ghes_estatus_cache) + (estatus_len)) 76 #define GHES_ESTATUS_FROM_CACHE(estatus_cache) \ 77 ((struct acpi_hest_generic_status *) \ 78 ((struct ghes_estatus_cache *)(estatus_cache) + 1)) 79 80 #define GHES_ESTATUS_NODE_LEN(estatus_len) \ 81 (sizeof(struct ghes_estatus_node) + (estatus_len)) 82 #define GHES_ESTATUS_FROM_NODE(estatus_node) \ 83 ((struct acpi_hest_generic_status *) \ 84 ((struct ghes_estatus_node *)(estatus_node) + 1)) 85 86 bool ghes_disable; 87 module_param_named(disable, ghes_disable, bool, 0); 88 89 /* 90 * All error sources notified with SCI shares one notifier function, 91 * so they need to be linked and checked one by one. This is applied 92 * to NMI too. 93 * 94 * RCU is used for these lists, so ghes_list_mutex is only used for 95 * list changing, not for traversing. 96 */ 97 static LIST_HEAD(ghes_sci); 98 static DEFINE_MUTEX(ghes_list_mutex); 99 100 /* 101 * Because the memory area used to transfer hardware error information 102 * from BIOS to Linux can be determined only in NMI, IRQ or timer 103 * handler, but general ioremap can not be used in atomic context, so 104 * a special version of atomic ioremap is implemented for that. 105 */ 106 107 /* 108 * Two virtual pages are used, one for IRQ/PROCESS context, the other for 109 * NMI context (optionally). 110 */ 111 #ifdef CONFIG_HAVE_ACPI_APEI_NMI 112 #define GHES_IOREMAP_PAGES 2 113 #else 114 #define GHES_IOREMAP_PAGES 1 115 #endif 116 #define GHES_IOREMAP_IRQ_PAGE(base) (base) 117 #define GHES_IOREMAP_NMI_PAGE(base) ((base) + PAGE_SIZE) 118 119 /* virtual memory area for atomic ioremap */ 120 static struct vm_struct *ghes_ioremap_area; 121 /* 122 * These 2 spinlock is used to prevent atomic ioremap virtual memory 123 * area from being mapped simultaneously. 124 */ 125 static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi); 126 static DEFINE_SPINLOCK(ghes_ioremap_lock_irq); 127 128 static struct gen_pool *ghes_estatus_pool; 129 static unsigned long ghes_estatus_pool_size_request; 130 131 struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE]; 132 static atomic_t ghes_estatus_cache_alloced; 133 134 static int ghes_ioremap_init(void) 135 { 136 ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES, 137 VM_IOREMAP, VMALLOC_START, VMALLOC_END); 138 if (!ghes_ioremap_area) { 139 pr_err(GHES_PFX "Failed to allocate virtual memory area for atomic ioremap.\n"); 140 return -ENOMEM; 141 } 142 143 return 0; 144 } 145 146 static void ghes_ioremap_exit(void) 147 { 148 free_vm_area(ghes_ioremap_area); 149 } 150 151 static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn) 152 { 153 unsigned long vaddr; 154 155 vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr); 156 ioremap_page_range(vaddr, vaddr + PAGE_SIZE, 157 pfn << PAGE_SHIFT, PAGE_KERNEL); 158 159 return (void __iomem *)vaddr; 160 } 161 162 static void __iomem *ghes_ioremap_pfn_irq(u64 pfn) 163 { 164 unsigned long vaddr; 165 166 vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr); 167 ioremap_page_range(vaddr, vaddr + PAGE_SIZE, 168 pfn << PAGE_SHIFT, PAGE_KERNEL); 169 170 return (void __iomem *)vaddr; 171 } 172 173 static void ghes_iounmap_nmi(void __iomem *vaddr_ptr) 174 { 175 unsigned long vaddr = (unsigned long __force)vaddr_ptr; 176 void *base = ghes_ioremap_area->addr; 177 178 BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base)); 179 unmap_kernel_range_noflush(vaddr, PAGE_SIZE); 180 arch_apei_flush_tlb_one(vaddr); 181 } 182 183 static void ghes_iounmap_irq(void __iomem *vaddr_ptr) 184 { 185 unsigned long vaddr = (unsigned long __force)vaddr_ptr; 186 void *base = ghes_ioremap_area->addr; 187 188 BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base)); 189 unmap_kernel_range_noflush(vaddr, PAGE_SIZE); 190 arch_apei_flush_tlb_one(vaddr); 191 } 192 193 static int ghes_estatus_pool_init(void) 194 { 195 ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1); 196 if (!ghes_estatus_pool) 197 return -ENOMEM; 198 return 0; 199 } 200 201 static void ghes_estatus_pool_free_chunk_page(struct gen_pool *pool, 202 struct gen_pool_chunk *chunk, 203 void *data) 204 { 205 free_page(chunk->start_addr); 206 } 207 208 static void ghes_estatus_pool_exit(void) 209 { 210 gen_pool_for_each_chunk(ghes_estatus_pool, 211 ghes_estatus_pool_free_chunk_page, NULL); 212 gen_pool_destroy(ghes_estatus_pool); 213 } 214 215 static int ghes_estatus_pool_expand(unsigned long len) 216 { 217 unsigned long i, pages, size, addr; 218 int ret; 219 220 ghes_estatus_pool_size_request += PAGE_ALIGN(len); 221 size = gen_pool_size(ghes_estatus_pool); 222 if (size >= ghes_estatus_pool_size_request) 223 return 0; 224 pages = (ghes_estatus_pool_size_request - size) / PAGE_SIZE; 225 for (i = 0; i < pages; i++) { 226 addr = __get_free_page(GFP_KERNEL); 227 if (!addr) 228 return -ENOMEM; 229 ret = gen_pool_add(ghes_estatus_pool, addr, PAGE_SIZE, -1); 230 if (ret) 231 return ret; 232 } 233 234 return 0; 235 } 236 237 static struct ghes *ghes_new(struct acpi_hest_generic *generic) 238 { 239 struct ghes *ghes; 240 unsigned int error_block_length; 241 int rc; 242 243 ghes = kzalloc(sizeof(*ghes), GFP_KERNEL); 244 if (!ghes) 245 return ERR_PTR(-ENOMEM); 246 ghes->generic = generic; 247 rc = apei_map_generic_address(&generic->error_status_address); 248 if (rc) 249 goto err_free; 250 error_block_length = generic->error_block_length; 251 if (error_block_length > GHES_ESTATUS_MAX_SIZE) { 252 pr_warning(FW_WARN GHES_PFX 253 "Error status block length is too long: %u for " 254 "generic hardware error source: %d.\n", 255 error_block_length, generic->header.source_id); 256 error_block_length = GHES_ESTATUS_MAX_SIZE; 257 } 258 ghes->estatus = kmalloc(error_block_length, GFP_KERNEL); 259 if (!ghes->estatus) { 260 rc = -ENOMEM; 261 goto err_unmap; 262 } 263 264 return ghes; 265 266 err_unmap: 267 apei_unmap_generic_address(&generic->error_status_address); 268 err_free: 269 kfree(ghes); 270 return ERR_PTR(rc); 271 } 272 273 static void ghes_fini(struct ghes *ghes) 274 { 275 kfree(ghes->estatus); 276 apei_unmap_generic_address(&ghes->generic->error_status_address); 277 } 278 279 static inline int ghes_severity(int severity) 280 { 281 switch (severity) { 282 case CPER_SEV_INFORMATIONAL: 283 return GHES_SEV_NO; 284 case CPER_SEV_CORRECTED: 285 return GHES_SEV_CORRECTED; 286 case CPER_SEV_RECOVERABLE: 287 return GHES_SEV_RECOVERABLE; 288 case CPER_SEV_FATAL: 289 return GHES_SEV_PANIC; 290 default: 291 /* Unknown, go panic */ 292 return GHES_SEV_PANIC; 293 } 294 } 295 296 static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, 297 int from_phys) 298 { 299 void __iomem *vaddr; 300 unsigned long flags = 0; 301 int in_nmi = in_nmi(); 302 u64 offset; 303 u32 trunk; 304 305 while (len > 0) { 306 offset = paddr - (paddr & PAGE_MASK); 307 if (in_nmi) { 308 raw_spin_lock(&ghes_ioremap_lock_nmi); 309 vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT); 310 } else { 311 spin_lock_irqsave(&ghes_ioremap_lock_irq, flags); 312 vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT); 313 } 314 trunk = PAGE_SIZE - offset; 315 trunk = min(trunk, len); 316 if (from_phys) 317 memcpy_fromio(buffer, vaddr + offset, trunk); 318 else 319 memcpy_toio(vaddr + offset, buffer, trunk); 320 len -= trunk; 321 paddr += trunk; 322 buffer += trunk; 323 if (in_nmi) { 324 ghes_iounmap_nmi(vaddr); 325 raw_spin_unlock(&ghes_ioremap_lock_nmi); 326 } else { 327 ghes_iounmap_irq(vaddr); 328 spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags); 329 } 330 } 331 } 332 333 static int ghes_read_estatus(struct ghes *ghes, int silent) 334 { 335 struct acpi_hest_generic *g = ghes->generic; 336 u64 buf_paddr; 337 u32 len; 338 int rc; 339 340 rc = apei_read(&buf_paddr, &g->error_status_address); 341 if (rc) { 342 if (!silent && printk_ratelimit()) 343 pr_warning(FW_WARN GHES_PFX 344 "Failed to read error status block address for hardware error source: %d.\n", 345 g->header.source_id); 346 return -EIO; 347 } 348 if (!buf_paddr) 349 return -ENOENT; 350 351 ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, 352 sizeof(*ghes->estatus), 1); 353 if (!ghes->estatus->block_status) 354 return -ENOENT; 355 356 ghes->buffer_paddr = buf_paddr; 357 ghes->flags |= GHES_TO_CLEAR; 358 359 rc = -EIO; 360 len = cper_estatus_len(ghes->estatus); 361 if (len < sizeof(*ghes->estatus)) 362 goto err_read_block; 363 if (len > ghes->generic->error_block_length) 364 goto err_read_block; 365 if (cper_estatus_check_header(ghes->estatus)) 366 goto err_read_block; 367 ghes_copy_tofrom_phys(ghes->estatus + 1, 368 buf_paddr + sizeof(*ghes->estatus), 369 len - sizeof(*ghes->estatus), 1); 370 if (cper_estatus_check(ghes->estatus)) 371 goto err_read_block; 372 rc = 0; 373 374 err_read_block: 375 if (rc && !silent && printk_ratelimit()) 376 pr_warning(FW_WARN GHES_PFX 377 "Failed to read error status block!\n"); 378 return rc; 379 } 380 381 static void ghes_clear_estatus(struct ghes *ghes) 382 { 383 ghes->estatus->block_status = 0; 384 if (!(ghes->flags & GHES_TO_CLEAR)) 385 return; 386 ghes_copy_tofrom_phys(ghes->estatus, ghes->buffer_paddr, 387 sizeof(ghes->estatus->block_status), 0); 388 ghes->flags &= ~GHES_TO_CLEAR; 389 } 390 391 static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int sev) 392 { 393 #ifdef CONFIG_ACPI_APEI_MEMORY_FAILURE 394 unsigned long pfn; 395 int flags = -1; 396 int sec_sev = ghes_severity(gdata->error_severity); 397 struct cper_sec_mem_err *mem_err; 398 mem_err = (struct cper_sec_mem_err *)(gdata + 1); 399 400 if (!(mem_err->validation_bits & CPER_MEM_VALID_PA)) 401 return; 402 403 pfn = mem_err->physical_addr >> PAGE_SHIFT; 404 if (!pfn_valid(pfn)) { 405 pr_warn_ratelimited(FW_WARN GHES_PFX 406 "Invalid address in generic error data: %#llx\n", 407 mem_err->physical_addr); 408 return; 409 } 410 411 /* iff following two events can be handled properly by now */ 412 if (sec_sev == GHES_SEV_CORRECTED && 413 (gdata->flags & CPER_SEC_ERROR_THRESHOLD_EXCEEDED)) 414 flags = MF_SOFT_OFFLINE; 415 if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE) 416 flags = 0; 417 418 if (flags != -1) 419 memory_failure_queue(pfn, 0, flags); 420 #endif 421 } 422 423 static void ghes_do_proc(struct ghes *ghes, 424 const struct acpi_hest_generic_status *estatus) 425 { 426 int sev, sec_sev; 427 struct acpi_hest_generic_data *gdata; 428 429 sev = ghes_severity(estatus->error_severity); 430 apei_estatus_for_each_section(estatus, gdata) { 431 sec_sev = ghes_severity(gdata->error_severity); 432 if (!uuid_le_cmp(*(uuid_le *)gdata->section_type, 433 CPER_SEC_PLATFORM_MEM)) { 434 struct cper_sec_mem_err *mem_err; 435 mem_err = (struct cper_sec_mem_err *)(gdata+1); 436 ghes_edac_report_mem_error(ghes, sev, mem_err); 437 438 arch_apei_report_mem_error(sev, mem_err); 439 ghes_handle_memory_failure(gdata, sev); 440 } 441 #ifdef CONFIG_ACPI_APEI_PCIEAER 442 else if (!uuid_le_cmp(*(uuid_le *)gdata->section_type, 443 CPER_SEC_PCIE)) { 444 struct cper_sec_pcie *pcie_err; 445 pcie_err = (struct cper_sec_pcie *)(gdata+1); 446 if (sev == GHES_SEV_RECOVERABLE && 447 sec_sev == GHES_SEV_RECOVERABLE && 448 pcie_err->validation_bits & CPER_PCIE_VALID_DEVICE_ID && 449 pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) { 450 unsigned int devfn; 451 int aer_severity; 452 453 devfn = PCI_DEVFN(pcie_err->device_id.device, 454 pcie_err->device_id.function); 455 aer_severity = cper_severity_to_aer(sev); 456 457 /* 458 * If firmware reset the component to contain 459 * the error, we must reinitialize it before 460 * use, so treat it as a fatal AER error. 461 */ 462 if (gdata->flags & CPER_SEC_RESET) 463 aer_severity = AER_FATAL; 464 465 aer_recover_queue(pcie_err->device_id.segment, 466 pcie_err->device_id.bus, 467 devfn, aer_severity, 468 (struct aer_capability_regs *) 469 pcie_err->aer_info); 470 } 471 472 } 473 #endif 474 } 475 } 476 477 static void __ghes_print_estatus(const char *pfx, 478 const struct acpi_hest_generic *generic, 479 const struct acpi_hest_generic_status *estatus) 480 { 481 static atomic_t seqno; 482 unsigned int curr_seqno; 483 char pfx_seq[64]; 484 485 if (pfx == NULL) { 486 if (ghes_severity(estatus->error_severity) <= 487 GHES_SEV_CORRECTED) 488 pfx = KERN_WARNING; 489 else 490 pfx = KERN_ERR; 491 } 492 curr_seqno = atomic_inc_return(&seqno); 493 snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}" HW_ERR, pfx, curr_seqno); 494 printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n", 495 pfx_seq, generic->header.source_id); 496 cper_estatus_print(pfx_seq, estatus); 497 } 498 499 static int ghes_print_estatus(const char *pfx, 500 const struct acpi_hest_generic *generic, 501 const struct acpi_hest_generic_status *estatus) 502 { 503 /* Not more than 2 messages every 5 seconds */ 504 static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2); 505 static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2); 506 struct ratelimit_state *ratelimit; 507 508 if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED) 509 ratelimit = &ratelimit_corrected; 510 else 511 ratelimit = &ratelimit_uncorrected; 512 if (__ratelimit(ratelimit)) { 513 __ghes_print_estatus(pfx, generic, estatus); 514 return 1; 515 } 516 return 0; 517 } 518 519 /* 520 * GHES error status reporting throttle, to report more kinds of 521 * errors, instead of just most frequently occurred errors. 522 */ 523 static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus) 524 { 525 u32 len; 526 int i, cached = 0; 527 unsigned long long now; 528 struct ghes_estatus_cache *cache; 529 struct acpi_hest_generic_status *cache_estatus; 530 531 len = cper_estatus_len(estatus); 532 rcu_read_lock(); 533 for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { 534 cache = rcu_dereference(ghes_estatus_caches[i]); 535 if (cache == NULL) 536 continue; 537 if (len != cache->estatus_len) 538 continue; 539 cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); 540 if (memcmp(estatus, cache_estatus, len)) 541 continue; 542 atomic_inc(&cache->count); 543 now = sched_clock(); 544 if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC) 545 cached = 1; 546 break; 547 } 548 rcu_read_unlock(); 549 return cached; 550 } 551 552 static struct ghes_estatus_cache *ghes_estatus_cache_alloc( 553 struct acpi_hest_generic *generic, 554 struct acpi_hest_generic_status *estatus) 555 { 556 int alloced; 557 u32 len, cache_len; 558 struct ghes_estatus_cache *cache; 559 struct acpi_hest_generic_status *cache_estatus; 560 561 alloced = atomic_add_return(1, &ghes_estatus_cache_alloced); 562 if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) { 563 atomic_dec(&ghes_estatus_cache_alloced); 564 return NULL; 565 } 566 len = cper_estatus_len(estatus); 567 cache_len = GHES_ESTATUS_CACHE_LEN(len); 568 cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len); 569 if (!cache) { 570 atomic_dec(&ghes_estatus_cache_alloced); 571 return NULL; 572 } 573 cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); 574 memcpy(cache_estatus, estatus, len); 575 cache->estatus_len = len; 576 atomic_set(&cache->count, 0); 577 cache->generic = generic; 578 cache->time_in = sched_clock(); 579 return cache; 580 } 581 582 static void ghes_estatus_cache_free(struct ghes_estatus_cache *cache) 583 { 584 u32 len; 585 586 len = cper_estatus_len(GHES_ESTATUS_FROM_CACHE(cache)); 587 len = GHES_ESTATUS_CACHE_LEN(len); 588 gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len); 589 atomic_dec(&ghes_estatus_cache_alloced); 590 } 591 592 static void ghes_estatus_cache_rcu_free(struct rcu_head *head) 593 { 594 struct ghes_estatus_cache *cache; 595 596 cache = container_of(head, struct ghes_estatus_cache, rcu); 597 ghes_estatus_cache_free(cache); 598 } 599 600 static void ghes_estatus_cache_add( 601 struct acpi_hest_generic *generic, 602 struct acpi_hest_generic_status *estatus) 603 { 604 int i, slot = -1, count; 605 unsigned long long now, duration, period, max_period = 0; 606 struct ghes_estatus_cache *cache, *slot_cache = NULL, *new_cache; 607 608 new_cache = ghes_estatus_cache_alloc(generic, estatus); 609 if (new_cache == NULL) 610 return; 611 rcu_read_lock(); 612 now = sched_clock(); 613 for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { 614 cache = rcu_dereference(ghes_estatus_caches[i]); 615 if (cache == NULL) { 616 slot = i; 617 slot_cache = NULL; 618 break; 619 } 620 duration = now - cache->time_in; 621 if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) { 622 slot = i; 623 slot_cache = cache; 624 break; 625 } 626 count = atomic_read(&cache->count); 627 period = duration; 628 do_div(period, (count + 1)); 629 if (period > max_period) { 630 max_period = period; 631 slot = i; 632 slot_cache = cache; 633 } 634 } 635 /* new_cache must be put into array after its contents are written */ 636 smp_wmb(); 637 if (slot != -1 && cmpxchg(ghes_estatus_caches + slot, 638 slot_cache, new_cache) == slot_cache) { 639 if (slot_cache) 640 call_rcu(&slot_cache->rcu, ghes_estatus_cache_rcu_free); 641 } else 642 ghes_estatus_cache_free(new_cache); 643 rcu_read_unlock(); 644 } 645 646 static int ghes_proc(struct ghes *ghes) 647 { 648 int rc; 649 650 rc = ghes_read_estatus(ghes, 0); 651 if (rc) 652 goto out; 653 if (!ghes_estatus_cached(ghes->estatus)) { 654 if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) 655 ghes_estatus_cache_add(ghes->generic, ghes->estatus); 656 } 657 ghes_do_proc(ghes, ghes->estatus); 658 out: 659 ghes_clear_estatus(ghes); 660 return 0; 661 } 662 663 static void ghes_add_timer(struct ghes *ghes) 664 { 665 struct acpi_hest_generic *g = ghes->generic; 666 unsigned long expire; 667 668 if (!g->notify.poll_interval) { 669 pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n", 670 g->header.source_id); 671 return; 672 } 673 expire = jiffies + msecs_to_jiffies(g->notify.poll_interval); 674 ghes->timer.expires = round_jiffies_relative(expire); 675 add_timer(&ghes->timer); 676 } 677 678 static void ghes_poll_func(unsigned long data) 679 { 680 struct ghes *ghes = (void *)data; 681 682 ghes_proc(ghes); 683 if (!(ghes->flags & GHES_EXITING)) 684 ghes_add_timer(ghes); 685 } 686 687 static irqreturn_t ghes_irq_func(int irq, void *data) 688 { 689 struct ghes *ghes = data; 690 int rc; 691 692 rc = ghes_proc(ghes); 693 if (rc) 694 return IRQ_NONE; 695 696 return IRQ_HANDLED; 697 } 698 699 static int ghes_notify_sci(struct notifier_block *this, 700 unsigned long event, void *data) 701 { 702 struct ghes *ghes; 703 int ret = NOTIFY_DONE; 704 705 rcu_read_lock(); 706 list_for_each_entry_rcu(ghes, &ghes_sci, list) { 707 if (!ghes_proc(ghes)) 708 ret = NOTIFY_OK; 709 } 710 rcu_read_unlock(); 711 712 return ret; 713 } 714 715 static struct notifier_block ghes_notifier_sci = { 716 .notifier_call = ghes_notify_sci, 717 }; 718 719 #ifdef CONFIG_HAVE_ACPI_APEI_NMI 720 /* 721 * printk is not safe in NMI context. So in NMI handler, we allocate 722 * required memory from lock-less memory allocator 723 * (ghes_estatus_pool), save estatus into it, put them into lock-less 724 * list (ghes_estatus_llist), then delay printk into IRQ context via 725 * irq_work (ghes_proc_irq_work). ghes_estatus_size_request record 726 * required pool size by all NMI error source. 727 */ 728 static struct llist_head ghes_estatus_llist; 729 static struct irq_work ghes_proc_irq_work; 730 731 /* 732 * NMI may be triggered on any CPU, so ghes_nmi_lock is used for 733 * mutual exclusion. 734 */ 735 static DEFINE_RAW_SPINLOCK(ghes_nmi_lock); 736 737 static LIST_HEAD(ghes_nmi); 738 739 static int ghes_panic_timeout __read_mostly = 30; 740 741 static struct llist_node *llist_nodes_reverse(struct llist_node *llnode) 742 { 743 struct llist_node *next, *tail = NULL; 744 745 while (llnode) { 746 next = llnode->next; 747 llnode->next = tail; 748 tail = llnode; 749 llnode = next; 750 } 751 752 return tail; 753 } 754 755 static void ghes_proc_in_irq(struct irq_work *irq_work) 756 { 757 struct llist_node *llnode, *next; 758 struct ghes_estatus_node *estatus_node; 759 struct acpi_hest_generic *generic; 760 struct acpi_hest_generic_status *estatus; 761 u32 len, node_len; 762 763 llnode = llist_del_all(&ghes_estatus_llist); 764 /* 765 * Because the time order of estatus in list is reversed, 766 * revert it back to proper order. 767 */ 768 llnode = llist_nodes_reverse(llnode); 769 while (llnode) { 770 next = llnode->next; 771 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 772 llnode); 773 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 774 len = cper_estatus_len(estatus); 775 node_len = GHES_ESTATUS_NODE_LEN(len); 776 ghes_do_proc(estatus_node->ghes, estatus); 777 if (!ghes_estatus_cached(estatus)) { 778 generic = estatus_node->generic; 779 if (ghes_print_estatus(NULL, generic, estatus)) 780 ghes_estatus_cache_add(generic, estatus); 781 } 782 gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, 783 node_len); 784 llnode = next; 785 } 786 } 787 788 static void ghes_print_queued_estatus(void) 789 { 790 struct llist_node *llnode; 791 struct ghes_estatus_node *estatus_node; 792 struct acpi_hest_generic *generic; 793 struct acpi_hest_generic_status *estatus; 794 u32 len, node_len; 795 796 llnode = llist_del_all(&ghes_estatus_llist); 797 /* 798 * Because the time order of estatus in list is reversed, 799 * revert it back to proper order. 800 */ 801 llnode = llist_nodes_reverse(llnode); 802 while (llnode) { 803 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 804 llnode); 805 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 806 len = cper_estatus_len(estatus); 807 node_len = GHES_ESTATUS_NODE_LEN(len); 808 generic = estatus_node->generic; 809 ghes_print_estatus(NULL, generic, estatus); 810 llnode = llnode->next; 811 } 812 } 813 814 static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) 815 { 816 struct ghes *ghes, *ghes_global = NULL; 817 int sev, sev_global = -1; 818 int ret = NMI_DONE; 819 820 raw_spin_lock(&ghes_nmi_lock); 821 list_for_each_entry_rcu(ghes, &ghes_nmi, list) { 822 if (ghes_read_estatus(ghes, 1)) { 823 ghes_clear_estatus(ghes); 824 continue; 825 } 826 sev = ghes_severity(ghes->estatus->error_severity); 827 if (sev > sev_global) { 828 sev_global = sev; 829 ghes_global = ghes; 830 } 831 ret = NMI_HANDLED; 832 } 833 834 if (ret == NMI_DONE) 835 goto out; 836 837 if (sev_global >= GHES_SEV_PANIC) { 838 oops_begin(); 839 ghes_print_queued_estatus(); 840 __ghes_print_estatus(KERN_EMERG, ghes_global->generic, 841 ghes_global->estatus); 842 /* reboot to log the error! */ 843 if (panic_timeout == 0) 844 panic_timeout = ghes_panic_timeout; 845 panic("Fatal hardware error!"); 846 } 847 848 list_for_each_entry_rcu(ghes, &ghes_nmi, list) { 849 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 850 u32 len, node_len; 851 struct ghes_estatus_node *estatus_node; 852 struct acpi_hest_generic_status *estatus; 853 #endif 854 if (!(ghes->flags & GHES_TO_CLEAR)) 855 continue; 856 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 857 if (ghes_estatus_cached(ghes->estatus)) 858 goto next; 859 /* Save estatus for further processing in IRQ context */ 860 len = cper_estatus_len(ghes->estatus); 861 node_len = GHES_ESTATUS_NODE_LEN(len); 862 estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, 863 node_len); 864 if (estatus_node) { 865 estatus_node->ghes = ghes; 866 estatus_node->generic = ghes->generic; 867 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 868 memcpy(estatus, ghes->estatus, len); 869 llist_add(&estatus_node->llnode, &ghes_estatus_llist); 870 } 871 next: 872 #endif 873 ghes_clear_estatus(ghes); 874 } 875 #ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 876 irq_work_queue(&ghes_proc_irq_work); 877 #endif 878 879 out: 880 raw_spin_unlock(&ghes_nmi_lock); 881 return ret; 882 } 883 884 static unsigned long ghes_esource_prealloc_size( 885 const struct acpi_hest_generic *generic) 886 { 887 unsigned long block_length, prealloc_records, prealloc_size; 888 889 block_length = min_t(unsigned long, generic->error_block_length, 890 GHES_ESTATUS_MAX_SIZE); 891 prealloc_records = max_t(unsigned long, 892 generic->records_to_preallocate, 1); 893 prealloc_size = min_t(unsigned long, block_length * prealloc_records, 894 GHES_ESOURCE_PREALLOC_MAX_SIZE); 895 896 return prealloc_size; 897 } 898 899 static void ghes_estatus_pool_shrink(unsigned long len) 900 { 901 ghes_estatus_pool_size_request -= PAGE_ALIGN(len); 902 } 903 904 static void ghes_nmi_add(struct ghes *ghes) 905 { 906 unsigned long len; 907 908 len = ghes_esource_prealloc_size(ghes->generic); 909 ghes_estatus_pool_expand(len); 910 mutex_lock(&ghes_list_mutex); 911 if (list_empty(&ghes_nmi)) 912 register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes"); 913 list_add_rcu(&ghes->list, &ghes_nmi); 914 mutex_unlock(&ghes_list_mutex); 915 } 916 917 static void ghes_nmi_remove(struct ghes *ghes) 918 { 919 unsigned long len; 920 921 mutex_lock(&ghes_list_mutex); 922 list_del_rcu(&ghes->list); 923 if (list_empty(&ghes_nmi)) 924 unregister_nmi_handler(NMI_LOCAL, "ghes"); 925 mutex_unlock(&ghes_list_mutex); 926 /* 927 * To synchronize with NMI handler, ghes can only be 928 * freed after NMI handler finishes. 929 */ 930 synchronize_rcu(); 931 len = ghes_esource_prealloc_size(ghes->generic); 932 ghes_estatus_pool_shrink(len); 933 } 934 935 static void ghes_nmi_init_cxt(void) 936 { 937 init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq); 938 } 939 #else /* CONFIG_HAVE_ACPI_APEI_NMI */ 940 static inline void ghes_nmi_add(struct ghes *ghes) 941 { 942 pr_err(GHES_PFX "ID: %d, trying to add NMI notification which is not supported!\n", 943 ghes->generic->header.source_id); 944 BUG(); 945 } 946 947 static inline void ghes_nmi_remove(struct ghes *ghes) 948 { 949 pr_err(GHES_PFX "ID: %d, trying to remove NMI notification which is not supported!\n", 950 ghes->generic->header.source_id); 951 BUG(); 952 } 953 954 static inline void ghes_nmi_init_cxt(void) 955 { 956 } 957 #endif /* CONFIG_HAVE_ACPI_APEI_NMI */ 958 959 static int ghes_probe(struct platform_device *ghes_dev) 960 { 961 struct acpi_hest_generic *generic; 962 struct ghes *ghes = NULL; 963 964 int rc = -EINVAL; 965 966 generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data; 967 if (!generic->enabled) 968 return -ENODEV; 969 970 switch (generic->notify.type) { 971 case ACPI_HEST_NOTIFY_POLLED: 972 case ACPI_HEST_NOTIFY_EXTERNAL: 973 case ACPI_HEST_NOTIFY_SCI: 974 break; 975 case ACPI_HEST_NOTIFY_NMI: 976 if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) { 977 pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n", 978 generic->header.source_id); 979 goto err; 980 } 981 break; 982 case ACPI_HEST_NOTIFY_LOCAL: 983 pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n", 984 generic->header.source_id); 985 goto err; 986 default: 987 pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n", 988 generic->notify.type, generic->header.source_id); 989 goto err; 990 } 991 992 rc = -EIO; 993 if (generic->error_block_length < 994 sizeof(struct acpi_hest_generic_status)) { 995 pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n", 996 generic->error_block_length, 997 generic->header.source_id); 998 goto err; 999 } 1000 ghes = ghes_new(generic); 1001 if (IS_ERR(ghes)) { 1002 rc = PTR_ERR(ghes); 1003 ghes = NULL; 1004 goto err; 1005 } 1006 1007 rc = ghes_edac_register(ghes, &ghes_dev->dev); 1008 if (rc < 0) 1009 goto err; 1010 1011 switch (generic->notify.type) { 1012 case ACPI_HEST_NOTIFY_POLLED: 1013 ghes->timer.function = ghes_poll_func; 1014 ghes->timer.data = (unsigned long)ghes; 1015 init_timer_deferrable(&ghes->timer); 1016 ghes_add_timer(ghes); 1017 break; 1018 case ACPI_HEST_NOTIFY_EXTERNAL: 1019 /* External interrupt vector is GSI */ 1020 rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq); 1021 if (rc) { 1022 pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n", 1023 generic->header.source_id); 1024 goto err_edac_unreg; 1025 } 1026 rc = request_irq(ghes->irq, ghes_irq_func, 0, "GHES IRQ", ghes); 1027 if (rc) { 1028 pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n", 1029 generic->header.source_id); 1030 goto err_edac_unreg; 1031 } 1032 break; 1033 case ACPI_HEST_NOTIFY_SCI: 1034 mutex_lock(&ghes_list_mutex); 1035 if (list_empty(&ghes_sci)) 1036 register_acpi_hed_notifier(&ghes_notifier_sci); 1037 list_add_rcu(&ghes->list, &ghes_sci); 1038 mutex_unlock(&ghes_list_mutex); 1039 break; 1040 case ACPI_HEST_NOTIFY_NMI: 1041 ghes_nmi_add(ghes); 1042 break; 1043 default: 1044 BUG(); 1045 } 1046 platform_set_drvdata(ghes_dev, ghes); 1047 1048 return 0; 1049 err_edac_unreg: 1050 ghes_edac_unregister(ghes); 1051 err: 1052 if (ghes) { 1053 ghes_fini(ghes); 1054 kfree(ghes); 1055 } 1056 return rc; 1057 } 1058 1059 static int ghes_remove(struct platform_device *ghes_dev) 1060 { 1061 struct ghes *ghes; 1062 struct acpi_hest_generic *generic; 1063 1064 ghes = platform_get_drvdata(ghes_dev); 1065 generic = ghes->generic; 1066 1067 ghes->flags |= GHES_EXITING; 1068 switch (generic->notify.type) { 1069 case ACPI_HEST_NOTIFY_POLLED: 1070 del_timer_sync(&ghes->timer); 1071 break; 1072 case ACPI_HEST_NOTIFY_EXTERNAL: 1073 free_irq(ghes->irq, ghes); 1074 break; 1075 case ACPI_HEST_NOTIFY_SCI: 1076 mutex_lock(&ghes_list_mutex); 1077 list_del_rcu(&ghes->list); 1078 if (list_empty(&ghes_sci)) 1079 unregister_acpi_hed_notifier(&ghes_notifier_sci); 1080 mutex_unlock(&ghes_list_mutex); 1081 break; 1082 case ACPI_HEST_NOTIFY_NMI: 1083 ghes_nmi_remove(ghes); 1084 break; 1085 default: 1086 BUG(); 1087 break; 1088 } 1089 1090 ghes_fini(ghes); 1091 1092 ghes_edac_unregister(ghes); 1093 1094 kfree(ghes); 1095 1096 platform_set_drvdata(ghes_dev, NULL); 1097 1098 return 0; 1099 } 1100 1101 static struct platform_driver ghes_platform_driver = { 1102 .driver = { 1103 .name = "GHES", 1104 .owner = THIS_MODULE, 1105 }, 1106 .probe = ghes_probe, 1107 .remove = ghes_remove, 1108 }; 1109 1110 static int __init ghes_init(void) 1111 { 1112 int rc; 1113 1114 if (acpi_disabled) 1115 return -ENODEV; 1116 1117 if (hest_disable) { 1118 pr_info(GHES_PFX "HEST is not enabled!\n"); 1119 return -EINVAL; 1120 } 1121 1122 if (ghes_disable) { 1123 pr_info(GHES_PFX "GHES is not enabled!\n"); 1124 return -EINVAL; 1125 } 1126 1127 ghes_nmi_init_cxt(); 1128 1129 rc = ghes_ioremap_init(); 1130 if (rc) 1131 goto err; 1132 1133 rc = ghes_estatus_pool_init(); 1134 if (rc) 1135 goto err_ioremap_exit; 1136 1137 rc = ghes_estatus_pool_expand(GHES_ESTATUS_CACHE_AVG_SIZE * 1138 GHES_ESTATUS_CACHE_ALLOCED_MAX); 1139 if (rc) 1140 goto err_pool_exit; 1141 1142 rc = platform_driver_register(&ghes_platform_driver); 1143 if (rc) 1144 goto err_pool_exit; 1145 1146 rc = apei_osc_setup(); 1147 if (rc == 0 && osc_sb_apei_support_acked) 1148 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n"); 1149 else if (rc == 0 && !osc_sb_apei_support_acked) 1150 pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n"); 1151 else if (rc && osc_sb_apei_support_acked) 1152 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n"); 1153 else 1154 pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n"); 1155 1156 return 0; 1157 err_pool_exit: 1158 ghes_estatus_pool_exit(); 1159 err_ioremap_exit: 1160 ghes_ioremap_exit(); 1161 err: 1162 return rc; 1163 } 1164 1165 static void __exit ghes_exit(void) 1166 { 1167 platform_driver_unregister(&ghes_platform_driver); 1168 ghes_estatus_pool_exit(); 1169 ghes_ioremap_exit(); 1170 } 1171 1172 module_init(ghes_init); 1173 module_exit(ghes_exit); 1174 1175 MODULE_AUTHOR("Huang Ying"); 1176 MODULE_DESCRIPTION("APEI Generic Hardware Error Source support"); 1177 MODULE_LICENSE("GPL"); 1178 MODULE_ALIAS("platform:GHES"); 1179