1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2001 Dave Engebretsen IBM Corporation 4 */ 5 6 #include <linux/sched.h> 7 #include <linux/interrupt.h> 8 #include <linux/irq.h> 9 #include <linux/of.h> 10 #include <linux/fs.h> 11 #include <linux/reboot.h> 12 #include <linux/irq_work.h> 13 14 #include <asm/machdep.h> 15 #include <asm/rtas.h> 16 #include <asm/firmware.h> 17 #include <asm/mce.h> 18 19 #include "pseries.h" 20 21 static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX]; 22 static DEFINE_SPINLOCK(ras_log_buf_lock); 23 24 static int ras_check_exception_token; 25 26 static void mce_process_errlog_event(struct irq_work *work); 27 static struct irq_work mce_errlog_process_work = { 28 .func = mce_process_errlog_event, 29 }; 30 31 #define EPOW_SENSOR_TOKEN 9 32 #define EPOW_SENSOR_INDEX 0 33 34 /* EPOW events counter variable */ 35 static int num_epow_events; 36 37 static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id); 38 static irqreturn_t ras_epow_interrupt(int irq, void *dev_id); 39 static irqreturn_t ras_error_interrupt(int irq, void *dev_id); 40 41 /* RTAS pseries MCE errorlog section. */ 42 struct pseries_mc_errorlog { 43 __be32 fru_id; 44 __be32 proc_id; 45 u8 error_type; 46 /* 47 * sub_err_type (1 byte). Bit fields depends on error_type 48 * 49 * MSB0 50 * | 51 * V 52 * 01234567 53 * XXXXXXXX 54 * 55 * For error_type == MC_ERROR_TYPE_UE 56 * XXXXXXXX 57 * X 1: Permanent or Transient UE. 58 * X 1: Effective address provided. 59 * X 1: Logical address provided. 60 * XX 2: Reserved. 61 * XXX 3: Type of UE error. 62 * 63 * For error_type != MC_ERROR_TYPE_UE 64 * XXXXXXXX 65 * X 1: Effective address provided. 66 * XXXXX 5: Reserved. 67 * XX 2: Type of SLB/ERAT/TLB error. 68 */ 69 u8 sub_err_type; 70 u8 reserved_1[6]; 71 __be64 effective_address; 72 __be64 logical_address; 73 } __packed; 74 75 /* RTAS pseries MCE error types */ 76 #define MC_ERROR_TYPE_UE 0x00 77 #define MC_ERROR_TYPE_SLB 0x01 78 #define MC_ERROR_TYPE_ERAT 0x02 79 #define MC_ERROR_TYPE_UNKNOWN 0x03 80 #define MC_ERROR_TYPE_TLB 0x04 81 #define MC_ERROR_TYPE_D_CACHE 0x05 82 #define MC_ERROR_TYPE_I_CACHE 0x07 83 84 /* RTAS pseries MCE error sub types */ 85 #define MC_ERROR_UE_INDETERMINATE 0 86 #define MC_ERROR_UE_IFETCH 1 87 #define MC_ERROR_UE_PAGE_TABLE_WALK_IFETCH 2 88 #define MC_ERROR_UE_LOAD_STORE 3 89 #define MC_ERROR_UE_PAGE_TABLE_WALK_LOAD_STORE 4 90 91 #define UE_EFFECTIVE_ADDR_PROVIDED 0x40 92 #define UE_LOGICAL_ADDR_PROVIDED 0x20 93 94 #define MC_ERROR_SLB_PARITY 0 95 #define MC_ERROR_SLB_MULTIHIT 1 96 #define MC_ERROR_SLB_INDETERMINATE 2 97 98 #define MC_ERROR_ERAT_PARITY 1 99 #define MC_ERROR_ERAT_MULTIHIT 2 100 #define MC_ERROR_ERAT_INDETERMINATE 3 101 102 #define MC_ERROR_TLB_PARITY 1 103 #define MC_ERROR_TLB_MULTIHIT 2 104 #define MC_ERROR_TLB_INDETERMINATE 3 105 106 static inline u8 rtas_mc_error_sub_type(const struct pseries_mc_errorlog *mlog) 107 { 108 switch (mlog->error_type) { 109 case MC_ERROR_TYPE_UE: 110 return (mlog->sub_err_type & 0x07); 111 case MC_ERROR_TYPE_SLB: 112 case MC_ERROR_TYPE_ERAT: 113 case MC_ERROR_TYPE_TLB: 114 return (mlog->sub_err_type & 0x03); 115 default: 116 return 0; 117 } 118 } 119 120 /* 121 * Enable the hotplug interrupt late because processing them may touch other 122 * devices or systems (e.g. hugepages) that have not been initialized at the 123 * subsys stage. 124 */ 125 static int __init init_ras_hotplug_IRQ(void) 126 { 127 struct device_node *np; 128 129 /* Hotplug Events */ 130 np = of_find_node_by_path("/event-sources/hot-plug-events"); 131 if (np != NULL) { 132 if (dlpar_workqueue_init() == 0) 133 request_event_sources_irqs(np, ras_hotplug_interrupt, 134 "RAS_HOTPLUG"); 135 of_node_put(np); 136 } 137 138 return 0; 139 } 140 machine_late_initcall(pseries, init_ras_hotplug_IRQ); 141 142 /* 143 * Initialize handlers for the set of interrupts caused by hardware errors 144 * and power system events. 145 */ 146 static int __init init_ras_IRQ(void) 147 { 148 struct device_node *np; 149 150 ras_check_exception_token = rtas_token("check-exception"); 151 152 /* Internal Errors */ 153 np = of_find_node_by_path("/event-sources/internal-errors"); 154 if (np != NULL) { 155 request_event_sources_irqs(np, ras_error_interrupt, 156 "RAS_ERROR"); 157 of_node_put(np); 158 } 159 160 /* EPOW Events */ 161 np = of_find_node_by_path("/event-sources/epow-events"); 162 if (np != NULL) { 163 request_event_sources_irqs(np, ras_epow_interrupt, "RAS_EPOW"); 164 of_node_put(np); 165 } 166 167 return 0; 168 } 169 machine_subsys_initcall(pseries, init_ras_IRQ); 170 171 #define EPOW_SHUTDOWN_NORMAL 1 172 #define EPOW_SHUTDOWN_ON_UPS 2 173 #define EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS 3 174 #define EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH 4 175 176 static void handle_system_shutdown(char event_modifier) 177 { 178 switch (event_modifier) { 179 case EPOW_SHUTDOWN_NORMAL: 180 pr_emerg("Power off requested\n"); 181 orderly_poweroff(true); 182 break; 183 184 case EPOW_SHUTDOWN_ON_UPS: 185 pr_emerg("Loss of system power detected. System is running on" 186 " UPS/battery. Check RTAS error log for details\n"); 187 break; 188 189 case EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS: 190 pr_emerg("Loss of system critical functions detected. Check" 191 " RTAS error log for details\n"); 192 orderly_poweroff(true); 193 break; 194 195 case EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH: 196 pr_emerg("High ambient temperature detected. Check RTAS" 197 " error log for details\n"); 198 orderly_poweroff(true); 199 break; 200 201 default: 202 pr_err("Unknown power/cooling shutdown event (modifier = %d)\n", 203 event_modifier); 204 } 205 } 206 207 struct epow_errorlog { 208 unsigned char sensor_value; 209 unsigned char event_modifier; 210 unsigned char extended_modifier; 211 unsigned char reserved; 212 unsigned char platform_reason; 213 }; 214 215 #define EPOW_RESET 0 216 #define EPOW_WARN_COOLING 1 217 #define EPOW_WARN_POWER 2 218 #define EPOW_SYSTEM_SHUTDOWN 3 219 #define EPOW_SYSTEM_HALT 4 220 #define EPOW_MAIN_ENCLOSURE 5 221 #define EPOW_POWER_OFF 7 222 223 static void rtas_parse_epow_errlog(struct rtas_error_log *log) 224 { 225 struct pseries_errorlog *pseries_log; 226 struct epow_errorlog *epow_log; 227 char action_code; 228 char modifier; 229 230 pseries_log = get_pseries_errorlog(log, PSERIES_ELOG_SECT_ID_EPOW); 231 if (pseries_log == NULL) 232 return; 233 234 epow_log = (struct epow_errorlog *)pseries_log->data; 235 action_code = epow_log->sensor_value & 0xF; /* bottom 4 bits */ 236 modifier = epow_log->event_modifier & 0xF; /* bottom 4 bits */ 237 238 switch (action_code) { 239 case EPOW_RESET: 240 if (num_epow_events) { 241 pr_info("Non critical power/cooling issue cleared\n"); 242 num_epow_events--; 243 } 244 break; 245 246 case EPOW_WARN_COOLING: 247 pr_info("Non-critical cooling issue detected. Check RTAS error" 248 " log for details\n"); 249 break; 250 251 case EPOW_WARN_POWER: 252 pr_info("Non-critical power issue detected. Check RTAS error" 253 " log for details\n"); 254 break; 255 256 case EPOW_SYSTEM_SHUTDOWN: 257 handle_system_shutdown(modifier); 258 break; 259 260 case EPOW_SYSTEM_HALT: 261 pr_emerg("Critical power/cooling issue detected. Check RTAS" 262 " error log for details. Powering off.\n"); 263 orderly_poweroff(true); 264 break; 265 266 case EPOW_MAIN_ENCLOSURE: 267 case EPOW_POWER_OFF: 268 pr_emerg("System about to lose power. Check RTAS error log " 269 " for details. Powering off immediately.\n"); 270 emergency_sync(); 271 kernel_power_off(); 272 break; 273 274 default: 275 pr_err("Unknown power/cooling event (action code = %d)\n", 276 action_code); 277 } 278 279 /* Increment epow events counter variable */ 280 if (action_code != EPOW_RESET) 281 num_epow_events++; 282 } 283 284 static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id) 285 { 286 struct pseries_errorlog *pseries_log; 287 struct pseries_hp_errorlog *hp_elog; 288 289 spin_lock(&ras_log_buf_lock); 290 291 rtas_call(ras_check_exception_token, 6, 1, NULL, 292 RTAS_VECTOR_EXTERNAL_INTERRUPT, virq_to_hw(irq), 293 RTAS_HOTPLUG_EVENTS, 0, __pa(&ras_log_buf), 294 rtas_get_error_log_max()); 295 296 pseries_log = get_pseries_errorlog((struct rtas_error_log *)ras_log_buf, 297 PSERIES_ELOG_SECT_ID_HOTPLUG); 298 hp_elog = (struct pseries_hp_errorlog *)pseries_log->data; 299 300 /* 301 * Since PCI hotplug is not currently supported on pseries, put PCI 302 * hotplug events on the ras_log_buf to be handled by rtas_errd. 303 */ 304 if (hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_MEM || 305 hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_CPU || 306 hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_PMEM) 307 queue_hotplug_event(hp_elog); 308 else 309 log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0); 310 311 spin_unlock(&ras_log_buf_lock); 312 return IRQ_HANDLED; 313 } 314 315 /* Handle environmental and power warning (EPOW) interrupts. */ 316 static irqreturn_t ras_epow_interrupt(int irq, void *dev_id) 317 { 318 int state; 319 int critical; 320 321 rtas_get_sensor_fast(EPOW_SENSOR_TOKEN, EPOW_SENSOR_INDEX, &state); 322 323 if (state > 3) 324 critical = 1; /* Time Critical */ 325 else 326 critical = 0; 327 328 spin_lock(&ras_log_buf_lock); 329 330 rtas_call(ras_check_exception_token, 6, 1, NULL, RTAS_VECTOR_EXTERNAL_INTERRUPT, 331 virq_to_hw(irq), RTAS_EPOW_WARNING, critical, __pa(&ras_log_buf), 332 rtas_get_error_log_max()); 333 334 log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0); 335 336 rtas_parse_epow_errlog((struct rtas_error_log *)ras_log_buf); 337 338 spin_unlock(&ras_log_buf_lock); 339 return IRQ_HANDLED; 340 } 341 342 /* 343 * Handle hardware error interrupts. 344 * 345 * RTAS check-exception is called to collect data on the exception. If 346 * the error is deemed recoverable, we log a warning and return. 347 * For nonrecoverable errors, an error is logged and we stop all processing 348 * as quickly as possible in order to prevent propagation of the failure. 349 */ 350 static irqreturn_t ras_error_interrupt(int irq, void *dev_id) 351 { 352 struct rtas_error_log *rtas_elog; 353 int status; 354 int fatal; 355 356 spin_lock(&ras_log_buf_lock); 357 358 status = rtas_call(ras_check_exception_token, 6, 1, NULL, 359 RTAS_VECTOR_EXTERNAL_INTERRUPT, 360 virq_to_hw(irq), 361 RTAS_INTERNAL_ERROR, 1 /* Time Critical */, 362 __pa(&ras_log_buf), 363 rtas_get_error_log_max()); 364 365 rtas_elog = (struct rtas_error_log *)ras_log_buf; 366 367 if (status == 0 && 368 rtas_error_severity(rtas_elog) >= RTAS_SEVERITY_ERROR_SYNC) 369 fatal = 1; 370 else 371 fatal = 0; 372 373 /* format and print the extended information */ 374 log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, fatal); 375 376 if (fatal) { 377 pr_emerg("Fatal hardware error detected. Check RTAS error" 378 " log for details. Powering off immediately\n"); 379 emergency_sync(); 380 kernel_power_off(); 381 } else { 382 pr_err("Recoverable hardware error detected\n"); 383 } 384 385 spin_unlock(&ras_log_buf_lock); 386 return IRQ_HANDLED; 387 } 388 389 /* 390 * Some versions of FWNMI place the buffer inside the 4kB page starting at 391 * 0x7000. Other versions place it inside the rtas buffer. We check both. 392 * Minimum size of the buffer is 16 bytes. 393 */ 394 #define VALID_FWNMI_BUFFER(A) \ 395 ((((A) >= 0x7000) && ((A) <= 0x8000 - 16)) || \ 396 (((A) >= rtas.base) && ((A) <= (rtas.base + rtas.size - 16)))) 397 398 static inline struct rtas_error_log *fwnmi_get_errlog(void) 399 { 400 return (struct rtas_error_log *)local_paca->mce_data_buf; 401 } 402 403 static __be64 *fwnmi_get_savep(struct pt_regs *regs) 404 { 405 unsigned long savep_ra; 406 407 /* Mask top two bits */ 408 savep_ra = regs->gpr[3] & ~(0x3UL << 62); 409 if (!VALID_FWNMI_BUFFER(savep_ra)) { 410 printk(KERN_ERR "FWNMI: corrupt r3 0x%016lx\n", regs->gpr[3]); 411 return NULL; 412 } 413 414 return __va(savep_ra); 415 } 416 417 /* 418 * Get the error information for errors coming through the 419 * FWNMI vectors. The pt_regs' r3 will be updated to reflect 420 * the actual r3 if possible, and a ptr to the error log entry 421 * will be returned if found. 422 * 423 * Use one buffer mce_data_buf per cpu to store RTAS error. 424 * 425 * The mce_data_buf does not have any locks or protection around it, 426 * if a second machine check comes in, or a system reset is done 427 * before we have logged the error, then we will get corruption in the 428 * error log. This is preferable over holding off on calling 429 * ibm,nmi-interlock which would result in us checkstopping if a 430 * second machine check did come in. 431 */ 432 static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs) 433 { 434 struct rtas_error_log *h; 435 __be64 *savep; 436 437 savep = fwnmi_get_savep(regs); 438 if (!savep) 439 return NULL; 440 441 regs->gpr[3] = be64_to_cpu(savep[0]); /* restore original r3 */ 442 443 h = (struct rtas_error_log *)&savep[1]; 444 /* Use the per cpu buffer from paca to store rtas error log */ 445 memset(local_paca->mce_data_buf, 0, RTAS_ERROR_LOG_MAX); 446 if (!rtas_error_extended(h)) { 447 memcpy(local_paca->mce_data_buf, h, sizeof(__u64)); 448 } else { 449 int len, error_log_length; 450 451 error_log_length = 8 + rtas_error_extended_log_length(h); 452 len = min_t(int, error_log_length, RTAS_ERROR_LOG_MAX); 453 memcpy(local_paca->mce_data_buf, h, len); 454 } 455 456 return (struct rtas_error_log *)local_paca->mce_data_buf; 457 } 458 459 /* Call this when done with the data returned by FWNMI_get_errinfo. 460 * It will release the saved data area for other CPUs in the 461 * partition to receive FWNMI errors. 462 */ 463 static void fwnmi_release_errinfo(void) 464 { 465 struct rtas_args rtas_args; 466 int ret; 467 468 /* 469 * On pseries, the machine check stack is limited to under 4GB, so 470 * args can be on-stack. 471 */ 472 rtas_call_unlocked(&rtas_args, ibm_nmi_interlock_token, 0, 1, NULL); 473 ret = be32_to_cpu(rtas_args.rets[0]); 474 if (ret != 0) 475 printk(KERN_ERR "FWNMI: nmi-interlock failed: %d\n", ret); 476 } 477 478 int pSeries_system_reset_exception(struct pt_regs *regs) 479 { 480 #ifdef __LITTLE_ENDIAN__ 481 /* 482 * Some firmware byteswaps SRR registers and gives incorrect SRR1. Try 483 * to detect the bad SRR1 pattern here. Flip the NIP back to correct 484 * endian for reporting purposes. Unfortunately the MSR can't be fixed, 485 * so clear it. It will be missing MSR_RI so we won't try to recover. 486 */ 487 if ((be64_to_cpu(regs->msr) & 488 (MSR_LE|MSR_RI|MSR_DR|MSR_IR|MSR_ME|MSR_PR| 489 MSR_ILE|MSR_HV|MSR_SF)) == (MSR_DR|MSR_SF)) { 490 regs_set_return_ip(regs, be64_to_cpu((__be64)regs->nip)); 491 regs_set_return_msr(regs, 0); 492 } 493 #endif 494 495 if (fwnmi_active) { 496 __be64 *savep; 497 498 /* 499 * Firmware (PowerVM and KVM) saves r3 to a save area like 500 * machine check, which is not exactly what PAPR (2.9) 501 * suggests but there is no way to detect otherwise, so this 502 * is the interface now. 503 * 504 * System resets do not save any error log or require an 505 * "ibm,nmi-interlock" rtas call to release. 506 */ 507 508 savep = fwnmi_get_savep(regs); 509 if (savep) 510 regs->gpr[3] = be64_to_cpu(savep[0]); /* restore original r3 */ 511 } 512 513 if (smp_handle_nmi_ipi(regs)) 514 return 1; 515 516 return 0; /* need to perform reset */ 517 } 518 519 static int mce_handle_err_realmode(int disposition, u8 error_type) 520 { 521 #ifdef CONFIG_PPC_BOOK3S_64 522 if (disposition == RTAS_DISP_NOT_RECOVERED) { 523 switch (error_type) { 524 case MC_ERROR_TYPE_ERAT: 525 flush_erat(); 526 disposition = RTAS_DISP_FULLY_RECOVERED; 527 break; 528 case MC_ERROR_TYPE_SLB: 529 /* 530 * Store the old slb content in paca before flushing. 531 * Print this when we go to virtual mode. 532 * There are chances that we may hit MCE again if there 533 * is a parity error on the SLB entry we trying to read 534 * for saving. Hence limit the slb saving to single 535 * level of recursion. 536 */ 537 if (local_paca->in_mce == 1) 538 slb_save_contents(local_paca->mce_faulty_slbs); 539 flush_and_reload_slb(); 540 disposition = RTAS_DISP_FULLY_RECOVERED; 541 break; 542 default: 543 break; 544 } 545 } else if (disposition == RTAS_DISP_LIMITED_RECOVERY) { 546 /* Platform corrected itself but could be degraded */ 547 pr_err("MCE: limited recovery, system may be degraded\n"); 548 disposition = RTAS_DISP_FULLY_RECOVERED; 549 } 550 #endif 551 return disposition; 552 } 553 554 static int mce_handle_err_virtmode(struct pt_regs *regs, 555 struct rtas_error_log *errp, 556 struct pseries_mc_errorlog *mce_log, 557 int disposition) 558 { 559 struct mce_error_info mce_err = { 0 }; 560 int initiator = rtas_error_initiator(errp); 561 int severity = rtas_error_severity(errp); 562 unsigned long eaddr = 0, paddr = 0; 563 u8 error_type, err_sub_type; 564 565 if (!mce_log) 566 goto out; 567 568 error_type = mce_log->error_type; 569 err_sub_type = rtas_mc_error_sub_type(mce_log); 570 571 if (initiator == RTAS_INITIATOR_UNKNOWN) 572 mce_err.initiator = MCE_INITIATOR_UNKNOWN; 573 else if (initiator == RTAS_INITIATOR_CPU) 574 mce_err.initiator = MCE_INITIATOR_CPU; 575 else if (initiator == RTAS_INITIATOR_PCI) 576 mce_err.initiator = MCE_INITIATOR_PCI; 577 else if (initiator == RTAS_INITIATOR_ISA) 578 mce_err.initiator = MCE_INITIATOR_ISA; 579 else if (initiator == RTAS_INITIATOR_MEMORY) 580 mce_err.initiator = MCE_INITIATOR_MEMORY; 581 else if (initiator == RTAS_INITIATOR_POWERMGM) 582 mce_err.initiator = MCE_INITIATOR_POWERMGM; 583 else 584 mce_err.initiator = MCE_INITIATOR_UNKNOWN; 585 586 if (severity == RTAS_SEVERITY_NO_ERROR) 587 mce_err.severity = MCE_SEV_NO_ERROR; 588 else if (severity == RTAS_SEVERITY_EVENT) 589 mce_err.severity = MCE_SEV_WARNING; 590 else if (severity == RTAS_SEVERITY_WARNING) 591 mce_err.severity = MCE_SEV_WARNING; 592 else if (severity == RTAS_SEVERITY_ERROR_SYNC) 593 mce_err.severity = MCE_SEV_SEVERE; 594 else if (severity == RTAS_SEVERITY_ERROR) 595 mce_err.severity = MCE_SEV_SEVERE; 596 else 597 mce_err.severity = MCE_SEV_FATAL; 598 599 if (severity <= RTAS_SEVERITY_ERROR_SYNC) 600 mce_err.sync_error = true; 601 else 602 mce_err.sync_error = false; 603 604 mce_err.error_type = MCE_ERROR_TYPE_UNKNOWN; 605 mce_err.error_class = MCE_ECLASS_UNKNOWN; 606 607 switch (error_type) { 608 case MC_ERROR_TYPE_UE: 609 mce_err.error_type = MCE_ERROR_TYPE_UE; 610 mce_common_process_ue(regs, &mce_err); 611 if (mce_err.ignore_event) 612 disposition = RTAS_DISP_FULLY_RECOVERED; 613 switch (err_sub_type) { 614 case MC_ERROR_UE_IFETCH: 615 mce_err.u.ue_error_type = MCE_UE_ERROR_IFETCH; 616 break; 617 case MC_ERROR_UE_PAGE_TABLE_WALK_IFETCH: 618 mce_err.u.ue_error_type = MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH; 619 break; 620 case MC_ERROR_UE_LOAD_STORE: 621 mce_err.u.ue_error_type = MCE_UE_ERROR_LOAD_STORE; 622 break; 623 case MC_ERROR_UE_PAGE_TABLE_WALK_LOAD_STORE: 624 mce_err.u.ue_error_type = MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE; 625 break; 626 case MC_ERROR_UE_INDETERMINATE: 627 default: 628 mce_err.u.ue_error_type = MCE_UE_ERROR_INDETERMINATE; 629 break; 630 } 631 if (mce_log->sub_err_type & UE_EFFECTIVE_ADDR_PROVIDED) 632 eaddr = be64_to_cpu(mce_log->effective_address); 633 634 if (mce_log->sub_err_type & UE_LOGICAL_ADDR_PROVIDED) { 635 paddr = be64_to_cpu(mce_log->logical_address); 636 } else if (mce_log->sub_err_type & UE_EFFECTIVE_ADDR_PROVIDED) { 637 unsigned long pfn; 638 639 pfn = addr_to_pfn(regs, eaddr); 640 if (pfn != ULONG_MAX) 641 paddr = pfn << PAGE_SHIFT; 642 } 643 644 break; 645 case MC_ERROR_TYPE_SLB: 646 mce_err.error_type = MCE_ERROR_TYPE_SLB; 647 switch (err_sub_type) { 648 case MC_ERROR_SLB_PARITY: 649 mce_err.u.slb_error_type = MCE_SLB_ERROR_PARITY; 650 break; 651 case MC_ERROR_SLB_MULTIHIT: 652 mce_err.u.slb_error_type = MCE_SLB_ERROR_MULTIHIT; 653 break; 654 case MC_ERROR_SLB_INDETERMINATE: 655 default: 656 mce_err.u.slb_error_type = MCE_SLB_ERROR_INDETERMINATE; 657 break; 658 } 659 if (mce_log->sub_err_type & 0x80) 660 eaddr = be64_to_cpu(mce_log->effective_address); 661 break; 662 case MC_ERROR_TYPE_ERAT: 663 mce_err.error_type = MCE_ERROR_TYPE_ERAT; 664 switch (err_sub_type) { 665 case MC_ERROR_ERAT_PARITY: 666 mce_err.u.erat_error_type = MCE_ERAT_ERROR_PARITY; 667 break; 668 case MC_ERROR_ERAT_MULTIHIT: 669 mce_err.u.erat_error_type = MCE_ERAT_ERROR_MULTIHIT; 670 break; 671 case MC_ERROR_ERAT_INDETERMINATE: 672 default: 673 mce_err.u.erat_error_type = MCE_ERAT_ERROR_INDETERMINATE; 674 break; 675 } 676 if (mce_log->sub_err_type & 0x80) 677 eaddr = be64_to_cpu(mce_log->effective_address); 678 break; 679 case MC_ERROR_TYPE_TLB: 680 mce_err.error_type = MCE_ERROR_TYPE_TLB; 681 switch (err_sub_type) { 682 case MC_ERROR_TLB_PARITY: 683 mce_err.u.tlb_error_type = MCE_TLB_ERROR_PARITY; 684 break; 685 case MC_ERROR_TLB_MULTIHIT: 686 mce_err.u.tlb_error_type = MCE_TLB_ERROR_MULTIHIT; 687 break; 688 case MC_ERROR_TLB_INDETERMINATE: 689 default: 690 mce_err.u.tlb_error_type = MCE_TLB_ERROR_INDETERMINATE; 691 break; 692 } 693 if (mce_log->sub_err_type & 0x80) 694 eaddr = be64_to_cpu(mce_log->effective_address); 695 break; 696 case MC_ERROR_TYPE_D_CACHE: 697 mce_err.error_type = MCE_ERROR_TYPE_DCACHE; 698 break; 699 case MC_ERROR_TYPE_I_CACHE: 700 mce_err.error_type = MCE_ERROR_TYPE_ICACHE; 701 break; 702 case MC_ERROR_TYPE_UNKNOWN: 703 default: 704 mce_err.error_type = MCE_ERROR_TYPE_UNKNOWN; 705 break; 706 } 707 out: 708 save_mce_event(regs, disposition == RTAS_DISP_FULLY_RECOVERED, 709 &mce_err, regs->nip, eaddr, paddr); 710 return disposition; 711 } 712 713 static int mce_handle_error(struct pt_regs *regs, struct rtas_error_log *errp) 714 { 715 struct pseries_errorlog *pseries_log; 716 struct pseries_mc_errorlog *mce_log = NULL; 717 int disposition = rtas_error_disposition(errp); 718 unsigned long msr; 719 u8 error_type; 720 721 if (!rtas_error_extended(errp)) 722 goto out; 723 724 pseries_log = get_pseries_errorlog(errp, PSERIES_ELOG_SECT_ID_MCE); 725 if (!pseries_log) 726 goto out; 727 728 mce_log = (struct pseries_mc_errorlog *)pseries_log->data; 729 error_type = mce_log->error_type; 730 731 disposition = mce_handle_err_realmode(disposition, error_type); 732 733 /* 734 * Enable translation as we will be accessing per-cpu variables 735 * in save_mce_event() which may fall outside RMO region, also 736 * leave it enabled because subsequently we will be queuing work 737 * to workqueues where again per-cpu variables accessed, besides 738 * fwnmi_release_errinfo() crashes when called in realmode on 739 * pseries. 740 * Note: All the realmode handling like flushing SLB entries for 741 * SLB multihit is done by now. 742 */ 743 out: 744 msr = mfmsr(); 745 mtmsr(msr | MSR_IR | MSR_DR); 746 747 disposition = mce_handle_err_virtmode(regs, errp, mce_log, 748 disposition); 749 750 /* 751 * Queue irq work to log this rtas event later. 752 * irq_work_queue uses per-cpu variables, so do this in virt 753 * mode as well. 754 */ 755 irq_work_queue(&mce_errlog_process_work); 756 757 mtmsr(msr); 758 759 return disposition; 760 } 761 762 /* 763 * Process MCE rtas errlog event. 764 */ 765 static void mce_process_errlog_event(struct irq_work *work) 766 { 767 struct rtas_error_log *err; 768 769 err = fwnmi_get_errlog(); 770 log_error((char *)err, ERR_TYPE_RTAS_LOG, 0); 771 } 772 773 /* 774 * See if we can recover from a machine check exception. 775 * This is only called on power4 (or above) and only via 776 * the Firmware Non-Maskable Interrupts (fwnmi) handler 777 * which provides the error analysis for us. 778 * 779 * Return 1 if corrected (or delivered a signal). 780 * Return 0 if there is nothing we can do. 781 */ 782 static int recover_mce(struct pt_regs *regs, struct machine_check_event *evt) 783 { 784 int recovered = 0; 785 786 if (regs_is_unrecoverable(regs)) { 787 /* If MSR_RI isn't set, we cannot recover */ 788 pr_err("Machine check interrupt unrecoverable: MSR(RI=0)\n"); 789 recovered = 0; 790 } else if (evt->disposition == MCE_DISPOSITION_RECOVERED) { 791 /* Platform corrected itself */ 792 recovered = 1; 793 } else if (evt->severity == MCE_SEV_FATAL) { 794 /* Fatal machine check */ 795 pr_err("Machine check interrupt is fatal\n"); 796 recovered = 0; 797 } 798 799 if (!recovered && evt->sync_error) { 800 /* 801 * Try to kill processes if we get a synchronous machine check 802 * (e.g., one caused by execution of this instruction). This 803 * will devolve into a panic if we try to kill init or are in 804 * an interrupt etc. 805 * 806 * TODO: Queue up this address for hwpoisioning later. 807 * TODO: This is not quite right for d-side machine 808 * checks ->nip is not necessarily the important 809 * address. 810 */ 811 if ((user_mode(regs))) { 812 _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip); 813 recovered = 1; 814 } else if (die_will_crash()) { 815 /* 816 * die() would kill the kernel, so better to go via 817 * the platform reboot code that will log the 818 * machine check. 819 */ 820 recovered = 0; 821 } else { 822 die_mce("Machine check", regs, SIGBUS); 823 recovered = 1; 824 } 825 } 826 827 return recovered; 828 } 829 830 /* 831 * Handle a machine check. 832 * 833 * Note that on Power 4 and beyond Firmware Non-Maskable Interrupts (fwnmi) 834 * should be present. If so the handler which called us tells us if the 835 * error was recovered (never true if RI=0). 836 * 837 * On hardware prior to Power 4 these exceptions were asynchronous which 838 * means we can't tell exactly where it occurred and so we can't recover. 839 */ 840 int pSeries_machine_check_exception(struct pt_regs *regs) 841 { 842 struct machine_check_event evt; 843 844 if (!get_mce_event(&evt, MCE_EVENT_RELEASE)) 845 return 0; 846 847 /* Print things out */ 848 if (evt.version != MCE_V1) { 849 pr_err("Machine Check Exception, Unknown event version %d !\n", 850 evt.version); 851 return 0; 852 } 853 machine_check_print_event_info(&evt, user_mode(regs), false); 854 855 if (recover_mce(regs, &evt)) 856 return 1; 857 858 return 0; 859 } 860 861 long pseries_machine_check_realmode(struct pt_regs *regs) 862 { 863 struct rtas_error_log *errp; 864 int disposition; 865 866 if (fwnmi_active) { 867 errp = fwnmi_get_errinfo(regs); 868 /* 869 * Call to fwnmi_release_errinfo() in real mode causes kernel 870 * to panic. Hence we will call it as soon as we go into 871 * virtual mode. 872 */ 873 disposition = mce_handle_error(regs, errp); 874 875 fwnmi_release_errinfo(); 876 877 if (disposition == RTAS_DISP_FULLY_RECOVERED) 878 return 1; 879 } 880 881 return 0; 882 } 883