// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2001 Dave Engebretsen IBM Corporation */ #include #include #include #include #include #include #include #include #include #include #include #include "pseries.h" static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX]; static DEFINE_SPINLOCK(ras_log_buf_lock); static int ras_check_exception_token; #define EPOW_SENSOR_TOKEN 9 #define EPOW_SENSOR_INDEX 0 /* EPOW events counter variable */ static int num_epow_events; static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id); static irqreturn_t ras_epow_interrupt(int irq, void *dev_id); static irqreturn_t ras_error_interrupt(int irq, void *dev_id); /* RTAS pseries MCE errorlog section. */ struct pseries_mc_errorlog { __be32 fru_id; __be32 proc_id; u8 error_type; /* * sub_err_type (1 byte). Bit fields depends on error_type * * MSB0 * | * V * 01234567 * XXXXXXXX * * For error_type == MC_ERROR_TYPE_UE * XXXXXXXX * X 1: Permanent or Transient UE. * X 1: Effective address provided. * X 1: Logical address provided. * XX 2: Reserved. * XXX 3: Type of UE error. * * For error_type == MC_ERROR_TYPE_SLB/ERAT/TLB * XXXXXXXX * X 1: Effective address provided. * XXXXX 5: Reserved. * XX 2: Type of SLB/ERAT/TLB error. * * For error_type == MC_ERROR_TYPE_CTRL_MEM_ACCESS * XXXXXXXX * X 1: Error causing address provided. * XXX 3: Type of error. * XXXX 4: Reserved. */ u8 sub_err_type; u8 reserved_1[6]; __be64 effective_address; __be64 logical_address; } __packed; /* RTAS pseries MCE error types */ #define MC_ERROR_TYPE_UE 0x00 #define MC_ERROR_TYPE_SLB 0x01 #define MC_ERROR_TYPE_ERAT 0x02 #define MC_ERROR_TYPE_UNKNOWN 0x03 #define MC_ERROR_TYPE_TLB 0x04 #define MC_ERROR_TYPE_D_CACHE 0x05 #define MC_ERROR_TYPE_I_CACHE 0x07 #define MC_ERROR_TYPE_CTRL_MEM_ACCESS 0x08 /* RTAS pseries MCE error sub types */ #define MC_ERROR_UE_INDETERMINATE 0 #define MC_ERROR_UE_IFETCH 1 #define MC_ERROR_UE_PAGE_TABLE_WALK_IFETCH 2 #define MC_ERROR_UE_LOAD_STORE 3 #define MC_ERROR_UE_PAGE_TABLE_WALK_LOAD_STORE 4 #define UE_EFFECTIVE_ADDR_PROVIDED 0x40 #define UE_LOGICAL_ADDR_PROVIDED 0x20 #define MC_EFFECTIVE_ADDR_PROVIDED 0x80 #define MC_ERROR_SLB_PARITY 0 #define MC_ERROR_SLB_MULTIHIT 1 #define MC_ERROR_SLB_INDETERMINATE 2 #define MC_ERROR_ERAT_PARITY 1 #define MC_ERROR_ERAT_MULTIHIT 2 #define MC_ERROR_ERAT_INDETERMINATE 3 #define MC_ERROR_TLB_PARITY 1 #define MC_ERROR_TLB_MULTIHIT 2 #define MC_ERROR_TLB_INDETERMINATE 3 #define MC_ERROR_CTRL_MEM_ACCESS_PTABLE_WALK 0 #define MC_ERROR_CTRL_MEM_ACCESS_OP_ACCESS 1 static inline u8 rtas_mc_error_sub_type(const struct pseries_mc_errorlog *mlog) { switch (mlog->error_type) { case MC_ERROR_TYPE_UE: return (mlog->sub_err_type & 0x07); case MC_ERROR_TYPE_SLB: case MC_ERROR_TYPE_ERAT: case MC_ERROR_TYPE_TLB: return (mlog->sub_err_type & 0x03); case MC_ERROR_TYPE_CTRL_MEM_ACCESS: return (mlog->sub_err_type & 0x70) >> 4; default: return 0; } } /* * Enable the hotplug interrupt late because processing them may touch other * devices or systems (e.g. hugepages) that have not been initialized at the * subsys stage. */ static int __init init_ras_hotplug_IRQ(void) { struct device_node *np; /* Hotplug Events */ np = of_find_node_by_path("/event-sources/hot-plug-events"); if (np != NULL) { if (dlpar_workqueue_init() == 0) request_event_sources_irqs(np, ras_hotplug_interrupt, "RAS_HOTPLUG"); of_node_put(np); } return 0; } machine_late_initcall(pseries, init_ras_hotplug_IRQ); /* * Initialize handlers for the set of interrupts caused by hardware errors * and power system events. */ static int __init init_ras_IRQ(void) { struct device_node *np; ras_check_exception_token = rtas_function_token(RTAS_FN_CHECK_EXCEPTION); /* Internal Errors */ np = of_find_node_by_path("/event-sources/internal-errors"); if (np != NULL) { request_event_sources_irqs(np, ras_error_interrupt, "RAS_ERROR"); of_node_put(np); } /* EPOW Events */ np = of_find_node_by_path("/event-sources/epow-events"); if (np != NULL) { request_event_sources_irqs(np, ras_epow_interrupt, "RAS_EPOW"); of_node_put(np); } return 0; } machine_subsys_initcall(pseries, init_ras_IRQ); #define EPOW_SHUTDOWN_NORMAL 1 #define EPOW_SHUTDOWN_ON_UPS 2 #define EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS 3 #define EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH 4 static void handle_system_shutdown(char event_modifier) { switch (event_modifier) { case EPOW_SHUTDOWN_NORMAL: pr_emerg("Power off requested\n"); orderly_poweroff(true); break; case EPOW_SHUTDOWN_ON_UPS: pr_emerg("Loss of system power detected. System is running on" " UPS/battery. Check RTAS error log for details\n"); break; case EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS: pr_emerg("Loss of system critical functions detected. Check" " RTAS error log for details\n"); orderly_poweroff(true); break; case EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH: pr_emerg("High ambient temperature detected. Check RTAS" " error log for details\n"); orderly_poweroff(true); break; default: pr_err("Unknown power/cooling shutdown event (modifier = %d)\n", event_modifier); } } struct epow_errorlog { unsigned char sensor_value; unsigned char event_modifier; unsigned char extended_modifier; unsigned char reserved; unsigned char platform_reason; }; #define EPOW_RESET 0 #define EPOW_WARN_COOLING 1 #define EPOW_WARN_POWER 2 #define EPOW_SYSTEM_SHUTDOWN 3 #define EPOW_SYSTEM_HALT 4 #define EPOW_MAIN_ENCLOSURE 5 #define EPOW_POWER_OFF 7 static void rtas_parse_epow_errlog(struct rtas_error_log *log) { struct pseries_errorlog *pseries_log; struct epow_errorlog *epow_log; char action_code; char modifier; pseries_log = get_pseries_errorlog(log, PSERIES_ELOG_SECT_ID_EPOW); if (pseries_log == NULL) return; epow_log = (struct epow_errorlog *)pseries_log->data; action_code = epow_log->sensor_value & 0xF; /* bottom 4 bits */ modifier = epow_log->event_modifier & 0xF; /* bottom 4 bits */ switch (action_code) { case EPOW_RESET: if (num_epow_events) { pr_info("Non critical power/cooling issue cleared\n"); num_epow_events--; } break; case EPOW_WARN_COOLING: pr_info("Non-critical cooling issue detected. Check RTAS error" " log for details\n"); break; case EPOW_WARN_POWER: pr_info("Non-critical power issue detected. Check RTAS error" " log for details\n"); break; case EPOW_SYSTEM_SHUTDOWN: handle_system_shutdown(modifier); break; case EPOW_SYSTEM_HALT: pr_emerg("Critical power/cooling issue detected. Check RTAS" " error log for details. Powering off.\n"); orderly_poweroff(true); break; case EPOW_MAIN_ENCLOSURE: case EPOW_POWER_OFF: pr_emerg("System about to lose power. Check RTAS error log " " for details. Powering off immediately.\n"); emergency_sync(); kernel_power_off(); break; default: pr_err("Unknown power/cooling event (action code = %d)\n", action_code); } /* Increment epow events counter variable */ if (action_code != EPOW_RESET) num_epow_events++; } static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id) { struct pseries_errorlog *pseries_log; struct pseries_hp_errorlog *hp_elog; spin_lock(&ras_log_buf_lock); rtas_call(ras_check_exception_token, 6, 1, NULL, RTAS_VECTOR_EXTERNAL_INTERRUPT, virq_to_hw(irq), RTAS_HOTPLUG_EVENTS, 0, __pa(&ras_log_buf), rtas_get_error_log_max()); pseries_log = get_pseries_errorlog((struct rtas_error_log *)ras_log_buf, PSERIES_ELOG_SECT_ID_HOTPLUG); hp_elog = (struct pseries_hp_errorlog *)pseries_log->data; /* * Since PCI hotplug is not currently supported on pseries, put PCI * hotplug events on the ras_log_buf to be handled by rtas_errd. */ if (hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_MEM || hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_CPU || hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_PMEM) queue_hotplug_event(hp_elog); else log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0); spin_unlock(&ras_log_buf_lock); return IRQ_HANDLED; } /* Handle environmental and power warning (EPOW) interrupts. */ static irqreturn_t ras_epow_interrupt(int irq, void *dev_id) { int state; int critical; rtas_get_sensor_fast(EPOW_SENSOR_TOKEN, EPOW_SENSOR_INDEX, &state); if (state > 3) critical = 1; /* Time Critical */ else critical = 0; spin_lock(&ras_log_buf_lock); rtas_call(ras_check_exception_token, 6, 1, NULL, RTAS_VECTOR_EXTERNAL_INTERRUPT, virq_to_hw(irq), RTAS_EPOW_WARNING, critical, __pa(&ras_log_buf), rtas_get_error_log_max()); log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0); rtas_parse_epow_errlog((struct rtas_error_log *)ras_log_buf); spin_unlock(&ras_log_buf_lock); return IRQ_HANDLED; } /* * Handle hardware error interrupts. * * RTAS check-exception is called to collect data on the exception. If * the error is deemed recoverable, we log a warning and return. * For nonrecoverable errors, an error is logged and we stop all processing * as quickly as possible in order to prevent propagation of the failure. */ static irqreturn_t ras_error_interrupt(int irq, void *dev_id) { struct rtas_error_log *rtas_elog; int status; int fatal; spin_lock(&ras_log_buf_lock); status = rtas_call(ras_check_exception_token, 6, 1, NULL, RTAS_VECTOR_EXTERNAL_INTERRUPT, virq_to_hw(irq), RTAS_INTERNAL_ERROR, 1 /* Time Critical */, __pa(&ras_log_buf), rtas_get_error_log_max()); rtas_elog = (struct rtas_error_log *)ras_log_buf; if (status == 0 && rtas_error_severity(rtas_elog) >= RTAS_SEVERITY_ERROR_SYNC) fatal = 1; else fatal = 0; /* format and print the extended information */ log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, fatal); if (fatal) { pr_emerg("Fatal hardware error detected. Check RTAS error" " log for details. Powering off immediately\n"); emergency_sync(); kernel_power_off(); } else { pr_err("Recoverable hardware error detected\n"); } spin_unlock(&ras_log_buf_lock); return IRQ_HANDLED; } /* * Some versions of FWNMI place the buffer inside the 4kB page starting at * 0x7000. Other versions place it inside the rtas buffer. We check both. * Minimum size of the buffer is 16 bytes. */ #define VALID_FWNMI_BUFFER(A) \ ((((A) >= 0x7000) && ((A) <= 0x8000 - 16)) || \ (((A) >= rtas.base) && ((A) <= (rtas.base + rtas.size - 16)))) static inline struct rtas_error_log *fwnmi_get_errlog(void) { return (struct rtas_error_log *)local_paca->mce_data_buf; } static __be64 *fwnmi_get_savep(struct pt_regs *regs) { unsigned long savep_ra; /* Mask top two bits */ savep_ra = regs->gpr[3] & ~(0x3UL << 62); if (!VALID_FWNMI_BUFFER(savep_ra)) { printk(KERN_ERR "FWNMI: corrupt r3 0x%016lx\n", regs->gpr[3]); return NULL; } return __va(savep_ra); } /* * Get the error information for errors coming through the * FWNMI vectors. The pt_regs' r3 will be updated to reflect * the actual r3 if possible, and a ptr to the error log entry * will be returned if found. * * Use one buffer mce_data_buf per cpu to store RTAS error. * * The mce_data_buf does not have any locks or protection around it, * if a second machine check comes in, or a system reset is done * before we have logged the error, then we will get corruption in the * error log. This is preferable over holding off on calling * ibm,nmi-interlock which would result in us checkstopping if a * second machine check did come in. */ static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs) { struct rtas_error_log *h; __be64 *savep; savep = fwnmi_get_savep(regs); if (!savep) return NULL; regs->gpr[3] = be64_to_cpu(savep[0]); /* restore original r3 */ h = (struct rtas_error_log *)&savep[1]; /* Use the per cpu buffer from paca to store rtas error log */ memset(local_paca->mce_data_buf, 0, RTAS_ERROR_LOG_MAX); if (!rtas_error_extended(h)) { memcpy(local_paca->mce_data_buf, h, sizeof(__u64)); } else { int len, error_log_length; error_log_length = 8 + rtas_error_extended_log_length(h); len = min_t(int, error_log_length, RTAS_ERROR_LOG_MAX); memcpy(local_paca->mce_data_buf, h, len); } return (struct rtas_error_log *)local_paca->mce_data_buf; } /* Call this when done with the data returned by FWNMI_get_errinfo. * It will release the saved data area for other CPUs in the * partition to receive FWNMI errors. */ static void fwnmi_release_errinfo(void) { struct rtas_args rtas_args; int ret; /* * On pseries, the machine check stack is limited to under 4GB, so * args can be on-stack. */ rtas_call_unlocked(&rtas_args, ibm_nmi_interlock_token, 0, 1, NULL); ret = be32_to_cpu(rtas_args.rets[0]); if (ret != 0) printk(KERN_ERR "FWNMI: nmi-interlock failed: %d\n", ret); } int pSeries_system_reset_exception(struct pt_regs *regs) { #ifdef __LITTLE_ENDIAN__ /* * Some firmware byteswaps SRR registers and gives incorrect SRR1. Try * to detect the bad SRR1 pattern here. Flip the NIP back to correct * endian for reporting purposes. Unfortunately the MSR can't be fixed, * so clear it. It will be missing MSR_RI so we won't try to recover. */ if ((be64_to_cpu(regs->msr) & (MSR_LE|MSR_RI|MSR_DR|MSR_IR|MSR_ME|MSR_PR| MSR_ILE|MSR_HV|MSR_SF)) == (MSR_DR|MSR_SF)) { regs_set_return_ip(regs, be64_to_cpu((__be64)regs->nip)); regs_set_return_msr(regs, 0); } #endif if (fwnmi_active) { __be64 *savep; /* * Firmware (PowerVM and KVM) saves r3 to a save area like * machine check, which is not exactly what PAPR (2.9) * suggests but there is no way to detect otherwise, so this * is the interface now. * * System resets do not save any error log or require an * "ibm,nmi-interlock" rtas call to release. */ savep = fwnmi_get_savep(regs); if (savep) regs->gpr[3] = be64_to_cpu(savep[0]); /* restore original r3 */ } if (smp_handle_nmi_ipi(regs)) return 1; return 0; /* need to perform reset */ } static int mce_handle_err_realmode(int disposition, u8 error_type) { #ifdef CONFIG_PPC_BOOK3S_64 if (disposition == RTAS_DISP_NOT_RECOVERED) { switch (error_type) { case MC_ERROR_TYPE_ERAT: flush_erat(); disposition = RTAS_DISP_FULLY_RECOVERED; break; case MC_ERROR_TYPE_SLB: #ifdef CONFIG_PPC_64S_HASH_MMU /* * Store the old slb content in paca before flushing. * Print this when we go to virtual mode. * There are chances that we may hit MCE again if there * is a parity error on the SLB entry we trying to read * for saving. Hence limit the slb saving to single * level of recursion. */ if (local_paca->in_mce == 1) slb_save_contents(local_paca->mce_faulty_slbs); flush_and_reload_slb(); disposition = RTAS_DISP_FULLY_RECOVERED; #endif break; default: break; } } else if (disposition == RTAS_DISP_LIMITED_RECOVERY) { /* Platform corrected itself but could be degraded */ pr_err("MCE: limited recovery, system may be degraded\n"); disposition = RTAS_DISP_FULLY_RECOVERED; } #endif return disposition; } static int mce_handle_err_virtmode(struct pt_regs *regs, struct rtas_error_log *errp, struct pseries_mc_errorlog *mce_log, int disposition) { struct mce_error_info mce_err = { 0 }; int initiator = rtas_error_initiator(errp); int severity = rtas_error_severity(errp); unsigned long eaddr = 0, paddr = 0; u8 error_type, err_sub_type; if (!mce_log) goto out; error_type = mce_log->error_type; err_sub_type = rtas_mc_error_sub_type(mce_log); if (initiator == RTAS_INITIATOR_UNKNOWN) mce_err.initiator = MCE_INITIATOR_UNKNOWN; else if (initiator == RTAS_INITIATOR_CPU) mce_err.initiator = MCE_INITIATOR_CPU; else if (initiator == RTAS_INITIATOR_PCI) mce_err.initiator = MCE_INITIATOR_PCI; else if (initiator == RTAS_INITIATOR_ISA) mce_err.initiator = MCE_INITIATOR_ISA; else if (initiator == RTAS_INITIATOR_MEMORY) mce_err.initiator = MCE_INITIATOR_MEMORY; else if (initiator == RTAS_INITIATOR_POWERMGM) mce_err.initiator = MCE_INITIATOR_POWERMGM; else mce_err.initiator = MCE_INITIATOR_UNKNOWN; if (severity == RTAS_SEVERITY_NO_ERROR) mce_err.severity = MCE_SEV_NO_ERROR; else if (severity == RTAS_SEVERITY_EVENT) mce_err.severity = MCE_SEV_WARNING; else if (severity == RTAS_SEVERITY_WARNING) mce_err.severity = MCE_SEV_WARNING; else if (severity == RTAS_SEVERITY_ERROR_SYNC) mce_err.severity = MCE_SEV_SEVERE; else if (severity == RTAS_SEVERITY_ERROR) mce_err.severity = MCE_SEV_SEVERE; else mce_err.severity = MCE_SEV_FATAL; if (severity <= RTAS_SEVERITY_ERROR_SYNC) mce_err.sync_error = true; else mce_err.sync_error = false; mce_err.error_type = MCE_ERROR_TYPE_UNKNOWN; mce_err.error_class = MCE_ECLASS_UNKNOWN; switch (error_type) { case MC_ERROR_TYPE_UE: mce_err.error_type = MCE_ERROR_TYPE_UE; mce_common_process_ue(regs, &mce_err); if (mce_err.ignore_event) disposition = RTAS_DISP_FULLY_RECOVERED; switch (err_sub_type) { case MC_ERROR_UE_IFETCH: mce_err.u.ue_error_type = MCE_UE_ERROR_IFETCH; break; case MC_ERROR_UE_PAGE_TABLE_WALK_IFETCH: mce_err.u.ue_error_type = MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH; break; case MC_ERROR_UE_LOAD_STORE: mce_err.u.ue_error_type = MCE_UE_ERROR_LOAD_STORE; break; case MC_ERROR_UE_PAGE_TABLE_WALK_LOAD_STORE: mce_err.u.ue_error_type = MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE; break; case MC_ERROR_UE_INDETERMINATE: default: mce_err.u.ue_error_type = MCE_UE_ERROR_INDETERMINATE; break; } if (mce_log->sub_err_type & UE_EFFECTIVE_ADDR_PROVIDED) eaddr = be64_to_cpu(mce_log->effective_address); if (mce_log->sub_err_type & UE_LOGICAL_ADDR_PROVIDED) { paddr = be64_to_cpu(mce_log->logical_address); } else if (mce_log->sub_err_type & UE_EFFECTIVE_ADDR_PROVIDED) { unsigned long pfn; pfn = addr_to_pfn(regs, eaddr); if (pfn != ULONG_MAX) paddr = pfn << PAGE_SHIFT; } break; case MC_ERROR_TYPE_SLB: mce_err.error_type = MCE_ERROR_TYPE_SLB; switch (err_sub_type) { case MC_ERROR_SLB_PARITY: mce_err.u.slb_error_type = MCE_SLB_ERROR_PARITY; break; case MC_ERROR_SLB_MULTIHIT: mce_err.u.slb_error_type = MCE_SLB_ERROR_MULTIHIT; break; case MC_ERROR_SLB_INDETERMINATE: default: mce_err.u.slb_error_type = MCE_SLB_ERROR_INDETERMINATE; break; } if (mce_log->sub_err_type & MC_EFFECTIVE_ADDR_PROVIDED) eaddr = be64_to_cpu(mce_log->effective_address); break; case MC_ERROR_TYPE_ERAT: mce_err.error_type = MCE_ERROR_TYPE_ERAT; switch (err_sub_type) { case MC_ERROR_ERAT_PARITY: mce_err.u.erat_error_type = MCE_ERAT_ERROR_PARITY; break; case MC_ERROR_ERAT_MULTIHIT: mce_err.u.erat_error_type = MCE_ERAT_ERROR_MULTIHIT; break; case MC_ERROR_ERAT_INDETERMINATE: default: mce_err.u.erat_error_type = MCE_ERAT_ERROR_INDETERMINATE; break; } if (mce_log->sub_err_type & MC_EFFECTIVE_ADDR_PROVIDED) eaddr = be64_to_cpu(mce_log->effective_address); break; case MC_ERROR_TYPE_TLB: mce_err.error_type = MCE_ERROR_TYPE_TLB; switch (err_sub_type) { case MC_ERROR_TLB_PARITY: mce_err.u.tlb_error_type = MCE_TLB_ERROR_PARITY; break; case MC_ERROR_TLB_MULTIHIT: mce_err.u.tlb_error_type = MCE_TLB_ERROR_MULTIHIT; break; case MC_ERROR_TLB_INDETERMINATE: default: mce_err.u.tlb_error_type = MCE_TLB_ERROR_INDETERMINATE; break; } if (mce_log->sub_err_type & MC_EFFECTIVE_ADDR_PROVIDED) eaddr = be64_to_cpu(mce_log->effective_address); break; case MC_ERROR_TYPE_D_CACHE: mce_err.error_type = MCE_ERROR_TYPE_DCACHE; break; case MC_ERROR_TYPE_I_CACHE: mce_err.error_type = MCE_ERROR_TYPE_ICACHE; break; case MC_ERROR_TYPE_CTRL_MEM_ACCESS: mce_err.error_type = MCE_ERROR_TYPE_RA; switch (err_sub_type) { case MC_ERROR_CTRL_MEM_ACCESS_PTABLE_WALK: mce_err.u.ra_error_type = MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN; break; case MC_ERROR_CTRL_MEM_ACCESS_OP_ACCESS: mce_err.u.ra_error_type = MCE_RA_ERROR_LOAD_STORE_FOREIGN; break; } if (mce_log->sub_err_type & MC_EFFECTIVE_ADDR_PROVIDED) eaddr = be64_to_cpu(mce_log->effective_address); break; case MC_ERROR_TYPE_UNKNOWN: default: mce_err.error_type = MCE_ERROR_TYPE_UNKNOWN; break; } out: save_mce_event(regs, disposition == RTAS_DISP_FULLY_RECOVERED, &mce_err, regs->nip, eaddr, paddr); return disposition; } static int mce_handle_error(struct pt_regs *regs, struct rtas_error_log *errp) { struct pseries_errorlog *pseries_log; struct pseries_mc_errorlog *mce_log = NULL; int disposition = rtas_error_disposition(errp); u8 error_type; if (!rtas_error_extended(errp)) goto out; pseries_log = get_pseries_errorlog(errp, PSERIES_ELOG_SECT_ID_MCE); if (!pseries_log) goto out; mce_log = (struct pseries_mc_errorlog *)pseries_log->data; error_type = mce_log->error_type; disposition = mce_handle_err_realmode(disposition, error_type); out: disposition = mce_handle_err_virtmode(regs, errp, mce_log, disposition); return disposition; } /* * Process MCE rtas errlog event. */ void pSeries_machine_check_log_err(void) { struct rtas_error_log *err; err = fwnmi_get_errlog(); log_error((char *)err, ERR_TYPE_RTAS_LOG, 0); } /* * See if we can recover from a machine check exception. * This is only called on power4 (or above) and only via * the Firmware Non-Maskable Interrupts (fwnmi) handler * which provides the error analysis for us. * * Return 1 if corrected (or delivered a signal). * Return 0 if there is nothing we can do. */ static int recover_mce(struct pt_regs *regs, struct machine_check_event *evt) { int recovered = 0; if (regs_is_unrecoverable(regs)) { /* If MSR_RI isn't set, we cannot recover */ pr_err("Machine check interrupt unrecoverable: MSR(RI=0)\n"); recovered = 0; } else if (evt->disposition == MCE_DISPOSITION_RECOVERED) { /* Platform corrected itself */ recovered = 1; } else if (evt->severity == MCE_SEV_FATAL) { /* Fatal machine check */ pr_err("Machine check interrupt is fatal\n"); recovered = 0; } if (!recovered && evt->sync_error) { /* * Try to kill processes if we get a synchronous machine check * (e.g., one caused by execution of this instruction). This * will devolve into a panic if we try to kill init or are in * an interrupt etc. * * TODO: Queue up this address for hwpoisioning later. * TODO: This is not quite right for d-side machine * checks ->nip is not necessarily the important * address. */ if ((user_mode(regs))) { _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip); recovered = 1; } else if (die_will_crash()) { /* * die() would kill the kernel, so better to go via * the platform reboot code that will log the * machine check. */ recovered = 0; } else { die_mce("Machine check", regs, SIGBUS); recovered = 1; } } return recovered; } /* * Handle a machine check. * * Note that on Power 4 and beyond Firmware Non-Maskable Interrupts (fwnmi) * should be present. If so the handler which called us tells us if the * error was recovered (never true if RI=0). * * On hardware prior to Power 4 these exceptions were asynchronous which * means we can't tell exactly where it occurred and so we can't recover. */ int pSeries_machine_check_exception(struct pt_regs *regs) { struct machine_check_event evt; if (!get_mce_event(&evt, MCE_EVENT_RELEASE)) return 0; /* Print things out */ if (evt.version != MCE_V1) { pr_err("Machine Check Exception, Unknown event version %d !\n", evt.version); return 0; } machine_check_print_event_info(&evt, user_mode(regs), false); if (recover_mce(regs, &evt)) return 1; return 0; } long pseries_machine_check_realmode(struct pt_regs *regs) { struct rtas_error_log *errp; int disposition; if (fwnmi_active) { errp = fwnmi_get_errinfo(regs); /* * Call to fwnmi_release_errinfo() in real mode causes kernel * to panic. Hence we will call it as soon as we go into * virtual mode. */ disposition = mce_handle_error(regs, errp); fwnmi_release_errinfo(); if (disposition == RTAS_DISP_FULLY_RECOVERED) return 1; } return 0; }