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 86bool ghes_disable; 87module_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 */ 97static LIST_HEAD(ghes_sci); 98static 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 */ 120static 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 */ 125static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi); 126static DEFINE_SPINLOCK(ghes_ioremap_lock_irq); 127 128static struct gen_pool *ghes_estatus_pool; 129static unsigned long ghes_estatus_pool_size_request; 130 131static struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE]; 132static atomic_t ghes_estatus_cache_alloced; 133 134static 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 146static void ghes_ioremap_exit(void) 147{ 148 free_vm_area(ghes_ioremap_area); 149} 150 151static 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 162static 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 173static 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 183static 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 193static 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 201static 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 208static 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 215static 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 237static 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 266err_unmap: 267 apei_unmap_generic_address(&generic->error_status_address); 268err_free: 269 kfree(ghes); 270 return ERR_PTR(rc); 271} 272 273static void ghes_fini(struct ghes *ghes) 274{ 275 kfree(ghes->estatus); 276 apei_unmap_generic_address(&ghes->generic->error_status_address); 277} 278 279static 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 296static 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 333static 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 374err_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 381static 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 391static 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 423static 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 477static 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 499static 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 */ 523static 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 552static 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 582static 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 592static 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 600static 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 646static 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); 658out: 659 ghes_clear_estatus(ghes); 660 return 0; 661} 662 663static 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 678static 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 687static 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 699static 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 715static 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 */ 728static struct llist_head ghes_estatus_llist; 729static 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 */ 735static DEFINE_RAW_SPINLOCK(ghes_nmi_lock); 736 737static LIST_HEAD(ghes_nmi); 738 739static int ghes_panic_timeout __read_mostly = 30; 740 741static void ghes_proc_in_irq(struct irq_work *irq_work) 742{ 743 struct llist_node *llnode, *next; 744 struct ghes_estatus_node *estatus_node; 745 struct acpi_hest_generic *generic; 746 struct acpi_hest_generic_status *estatus; 747 u32 len, node_len; 748 749 llnode = llist_del_all(&ghes_estatus_llist); 750 /* 751 * Because the time order of estatus in list is reversed, 752 * revert it back to proper order. 753 */ 754 llnode = llist_reverse_order(llnode); 755 while (llnode) { 756 next = llnode->next; 757 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 758 llnode); 759 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 760 len = cper_estatus_len(estatus); 761 node_len = GHES_ESTATUS_NODE_LEN(len); 762 ghes_do_proc(estatus_node->ghes, estatus); 763 if (!ghes_estatus_cached(estatus)) { 764 generic = estatus_node->generic; 765 if (ghes_print_estatus(NULL, generic, estatus)) 766 ghes_estatus_cache_add(generic, estatus); 767 } 768 gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, 769 node_len); 770 llnode = next; 771 } 772} 773 774static void ghes_print_queued_estatus(void) 775{ 776 struct llist_node *llnode; 777 struct ghes_estatus_node *estatus_node; 778 struct acpi_hest_generic *generic; 779 struct acpi_hest_generic_status *estatus; 780 u32 len, node_len; 781 782 llnode = llist_del_all(&ghes_estatus_llist); 783 /* 784 * Because the time order of estatus in list is reversed, 785 * revert it back to proper order. 786 */ 787 llnode = llist_reverse_order(llnode); 788 while (llnode) { 789 estatus_node = llist_entry(llnode, struct ghes_estatus_node, 790 llnode); 791 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 792 len = cper_estatus_len(estatus); 793 node_len = GHES_ESTATUS_NODE_LEN(len); 794 generic = estatus_node->generic; 795 ghes_print_estatus(NULL, generic, estatus); 796 llnode = llnode->next; 797 } 798} 799 800static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) 801{ 802 struct ghes *ghes, *ghes_global = NULL; 803 int sev, sev_global = -1; 804 int ret = NMI_DONE; 805 806 raw_spin_lock(&ghes_nmi_lock); 807 list_for_each_entry_rcu(ghes, &ghes_nmi, list) { 808 if (ghes_read_estatus(ghes, 1)) { 809 ghes_clear_estatus(ghes); 810 continue; 811 } 812 sev = ghes_severity(ghes->estatus->error_severity); 813 if (sev > sev_global) { 814 sev_global = sev; 815 ghes_global = ghes; 816 } 817 ret = NMI_HANDLED; 818 } 819 820 if (ret == NMI_DONE) 821 goto out; 822 823 if (sev_global >= GHES_SEV_PANIC) { 824 oops_begin(); 825 ghes_print_queued_estatus(); 826 __ghes_print_estatus(KERN_EMERG, ghes_global->generic, 827 ghes_global->estatus); 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 list_for_each_entry_rcu(ghes, &ghes_nmi, list) { 835#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 836 u32 len, node_len; 837 struct ghes_estatus_node *estatus_node; 838 struct acpi_hest_generic_status *estatus; 839#endif 840 if (!(ghes->flags & GHES_TO_CLEAR)) 841 continue; 842#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 843 if (ghes_estatus_cached(ghes->estatus)) 844 goto next; 845 /* Save estatus for further processing in IRQ context */ 846 len = cper_estatus_len(ghes->estatus); 847 node_len = GHES_ESTATUS_NODE_LEN(len); 848 estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, 849 node_len); 850 if (estatus_node) { 851 estatus_node->ghes = ghes; 852 estatus_node->generic = ghes->generic; 853 estatus = GHES_ESTATUS_FROM_NODE(estatus_node); 854 memcpy(estatus, ghes->estatus, len); 855 llist_add(&estatus_node->llnode, &ghes_estatus_llist); 856 } 857next: 858#endif 859 ghes_clear_estatus(ghes); 860 } 861#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG 862 irq_work_queue(&ghes_proc_irq_work); 863#endif 864 865out: 866 raw_spin_unlock(&ghes_nmi_lock); 867 return ret; 868} 869 870static unsigned long ghes_esource_prealloc_size( 871 const struct acpi_hest_generic *generic) 872{ 873 unsigned long block_length, prealloc_records, prealloc_size; 874 875 block_length = min_t(unsigned long, generic->error_block_length, 876 GHES_ESTATUS_MAX_SIZE); 877 prealloc_records = max_t(unsigned long, 878 generic->records_to_preallocate, 1); 879 prealloc_size = min_t(unsigned long, block_length * prealloc_records, 880 GHES_ESOURCE_PREALLOC_MAX_SIZE); 881 882 return prealloc_size; 883} 884 885static void ghes_estatus_pool_shrink(unsigned long len) 886{ 887 ghes_estatus_pool_size_request -= PAGE_ALIGN(len); 888} 889 890static void ghes_nmi_add(struct ghes *ghes) 891{ 892 unsigned long len; 893 894 len = ghes_esource_prealloc_size(ghes->generic); 895 ghes_estatus_pool_expand(len); 896 mutex_lock(&ghes_list_mutex); 897 if (list_empty(&ghes_nmi)) 898 register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes"); 899 list_add_rcu(&ghes->list, &ghes_nmi); 900 mutex_unlock(&ghes_list_mutex); 901} 902 903static void ghes_nmi_remove(struct ghes *ghes) 904{ 905 unsigned long len; 906 907 mutex_lock(&ghes_list_mutex); 908 list_del_rcu(&ghes->list); 909 if (list_empty(&ghes_nmi)) 910 unregister_nmi_handler(NMI_LOCAL, "ghes"); 911 mutex_unlock(&ghes_list_mutex); 912 /* 913 * To synchronize with NMI handler, ghes can only be 914 * freed after NMI handler finishes. 915 */ 916 synchronize_rcu(); 917 len = ghes_esource_prealloc_size(ghes->generic); 918 ghes_estatus_pool_shrink(len); 919} 920 921static void ghes_nmi_init_cxt(void) 922{ 923 init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq); 924} 925#else /* CONFIG_HAVE_ACPI_APEI_NMI */ 926static inline void ghes_nmi_add(struct ghes *ghes) 927{ 928 pr_err(GHES_PFX "ID: %d, trying to add NMI notification which is not supported!\n", 929 ghes->generic->header.source_id); 930 BUG(); 931} 932 933static inline void ghes_nmi_remove(struct ghes *ghes) 934{ 935 pr_err(GHES_PFX "ID: %d, trying to remove NMI notification which is not supported!\n", 936 ghes->generic->header.source_id); 937 BUG(); 938} 939 940static inline void ghes_nmi_init_cxt(void) 941{ 942} 943#endif /* CONFIG_HAVE_ACPI_APEI_NMI */ 944 945static int ghes_probe(struct platform_device *ghes_dev) 946{ 947 struct acpi_hest_generic *generic; 948 struct ghes *ghes = NULL; 949 950 int rc = -EINVAL; 951 952 generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data; 953 if (!generic->enabled) 954 return -ENODEV; 955 956 switch (generic->notify.type) { 957 case ACPI_HEST_NOTIFY_POLLED: 958 case ACPI_HEST_NOTIFY_EXTERNAL: 959 case ACPI_HEST_NOTIFY_SCI: 960 break; 961 case ACPI_HEST_NOTIFY_NMI: 962 if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) { 963 pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n", 964 generic->header.source_id); 965 goto err; 966 } 967 break; 968 case ACPI_HEST_NOTIFY_LOCAL: 969 pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n", 970 generic->header.source_id); 971 goto err; 972 default: 973 pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n", 974 generic->notify.type, generic->header.source_id); 975 goto err; 976 } 977 978 rc = -EIO; 979 if (generic->error_block_length < 980 sizeof(struct acpi_hest_generic_status)) { 981 pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n", 982 generic->error_block_length, 983 generic->header.source_id); 984 goto err; 985 } 986 ghes = ghes_new(generic); 987 if (IS_ERR(ghes)) { 988 rc = PTR_ERR(ghes); 989 ghes = NULL; 990 goto err; 991 } 992 993 rc = ghes_edac_register(ghes, &ghes_dev->dev); 994 if (rc < 0) 995 goto err; 996 997 switch (generic->notify.type) { 998 case ACPI_HEST_NOTIFY_POLLED: 999 ghes->timer.function = ghes_poll_func; 1000 ghes->timer.data = (unsigned long)ghes; 1001 init_timer_deferrable(&ghes->timer); 1002 ghes_add_timer(ghes); 1003 break; 1004 case ACPI_HEST_NOTIFY_EXTERNAL: 1005 /* External interrupt vector is GSI */ 1006 rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq); 1007 if (rc) { 1008 pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n", 1009 generic->header.source_id); 1010 goto err_edac_unreg; 1011 } 1012 rc = request_irq(ghes->irq, ghes_irq_func, 0, "GHES IRQ", ghes); 1013 if (rc) { 1014 pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n", 1015 generic->header.source_id); 1016 goto err_edac_unreg; 1017 } 1018 break; 1019 case ACPI_HEST_NOTIFY_SCI: 1020 mutex_lock(&ghes_list_mutex); 1021 if (list_empty(&ghes_sci)) 1022 register_acpi_hed_notifier(&ghes_notifier_sci); 1023 list_add_rcu(&ghes->list, &ghes_sci); 1024 mutex_unlock(&ghes_list_mutex); 1025 break; 1026 case ACPI_HEST_NOTIFY_NMI: 1027 ghes_nmi_add(ghes); 1028 break; 1029 default: 1030 BUG(); 1031 } 1032 platform_set_drvdata(ghes_dev, ghes); 1033 1034 return 0; 1035err_edac_unreg: 1036 ghes_edac_unregister(ghes); 1037err: 1038 if (ghes) { 1039 ghes_fini(ghes); 1040 kfree(ghes); 1041 } 1042 return rc; 1043} 1044 1045static int ghes_remove(struct platform_device *ghes_dev) 1046{ 1047 struct ghes *ghes; 1048 struct acpi_hest_generic *generic; 1049 1050 ghes = platform_get_drvdata(ghes_dev); 1051 generic = ghes->generic; 1052 1053 ghes->flags |= GHES_EXITING; 1054 switch (generic->notify.type) { 1055 case ACPI_HEST_NOTIFY_POLLED: 1056 del_timer_sync(&ghes->timer); 1057 break; 1058 case ACPI_HEST_NOTIFY_EXTERNAL: 1059 free_irq(ghes->irq, ghes); 1060 break; 1061 case ACPI_HEST_NOTIFY_SCI: 1062 mutex_lock(&ghes_list_mutex); 1063 list_del_rcu(&ghes->list); 1064 if (list_empty(&ghes_sci)) 1065 unregister_acpi_hed_notifier(&ghes_notifier_sci); 1066 mutex_unlock(&ghes_list_mutex); 1067 break; 1068 case ACPI_HEST_NOTIFY_NMI: 1069 ghes_nmi_remove(ghes); 1070 break; 1071 default: 1072 BUG(); 1073 break; 1074 } 1075 1076 ghes_fini(ghes); 1077 1078 ghes_edac_unregister(ghes); 1079 1080 kfree(ghes); 1081 1082 platform_set_drvdata(ghes_dev, NULL); 1083 1084 return 0; 1085} 1086 1087static struct platform_driver ghes_platform_driver = { 1088 .driver = { 1089 .name = "GHES", 1090 }, 1091 .probe = ghes_probe, 1092 .remove = ghes_remove, 1093}; 1094 1095static int __init ghes_init(void) 1096{ 1097 int rc; 1098 1099 if (acpi_disabled) 1100 return -ENODEV; 1101 1102 if (hest_disable) { 1103 pr_info(GHES_PFX "HEST is not enabled!\n"); 1104 return -EINVAL; 1105 } 1106 1107 if (ghes_disable) { 1108 pr_info(GHES_PFX "GHES is not enabled!\n"); 1109 return -EINVAL; 1110 } 1111 1112 ghes_nmi_init_cxt(); 1113 1114 rc = ghes_ioremap_init(); 1115 if (rc) 1116 goto err; 1117 1118 rc = ghes_estatus_pool_init(); 1119 if (rc) 1120 goto err_ioremap_exit; 1121 1122 rc = ghes_estatus_pool_expand(GHES_ESTATUS_CACHE_AVG_SIZE * 1123 GHES_ESTATUS_CACHE_ALLOCED_MAX); 1124 if (rc) 1125 goto err_pool_exit; 1126 1127 rc = platform_driver_register(&ghes_platform_driver); 1128 if (rc) 1129 goto err_pool_exit; 1130 1131 rc = apei_osc_setup(); 1132 if (rc == 0 && osc_sb_apei_support_acked) 1133 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n"); 1134 else if (rc == 0 && !osc_sb_apei_support_acked) 1135 pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n"); 1136 else if (rc && osc_sb_apei_support_acked) 1137 pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n"); 1138 else 1139 pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n"); 1140 1141 return 0; 1142err_pool_exit: 1143 ghes_estatus_pool_exit(); 1144err_ioremap_exit: 1145 ghes_ioremap_exit(); 1146err: 1147 return rc; 1148} 1149 1150static void __exit ghes_exit(void) 1151{ 1152 platform_driver_unregister(&ghes_platform_driver); 1153 ghes_estatus_pool_exit(); 1154 ghes_ioremap_exit(); 1155} 1156 1157module_init(ghes_init); 1158module_exit(ghes_exit); 1159 1160MODULE_AUTHOR("Huang Ying"); 1161MODULE_DESCRIPTION("APEI Generic Hardware Error Source support"); 1162MODULE_LICENSE("GPL"); 1163MODULE_ALIAS("platform:GHES"); 1164