diff options
Diffstat (limited to 'arch/powerpc/kernel/mce.c')
| -rw-r--r-- | arch/powerpc/kernel/mce.c | 767 |
1 files changed, 767 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c new file mode 100644 index 000000000..6c5d30fba --- /dev/null +++ b/arch/powerpc/kernel/mce.c @@ -0,0 +1,767 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Machine check exception handling. + * + * Copyright 2013 IBM Corporation + * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> + */ + +#undef DEBUG +#define pr_fmt(fmt) "mce: " fmt + +#include <linux/hardirq.h> +#include <linux/types.h> +#include <linux/ptrace.h> +#include <linux/percpu.h> +#include <linux/export.h> +#include <linux/irq_work.h> +#include <linux/extable.h> +#include <linux/ftrace.h> +#include <linux/memblock.h> +#include <linux/of.h> + +#include <asm/interrupt.h> +#include <asm/machdep.h> +#include <asm/mce.h> +#include <asm/nmi.h> + +#include "setup.h" + +static void machine_check_ue_event(struct machine_check_event *evt); +static void machine_process_ue_event(struct work_struct *work); + +static DECLARE_WORK(mce_ue_event_work, machine_process_ue_event); + +static BLOCKING_NOTIFIER_HEAD(mce_notifier_list); + +int mce_register_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&mce_notifier_list, nb); +} +EXPORT_SYMBOL_GPL(mce_register_notifier); + +int mce_unregister_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&mce_notifier_list, nb); +} +EXPORT_SYMBOL_GPL(mce_unregister_notifier); + +static void mce_set_error_info(struct machine_check_event *mce, + struct mce_error_info *mce_err) +{ + mce->error_type = mce_err->error_type; + switch (mce_err->error_type) { + case MCE_ERROR_TYPE_UE: + mce->u.ue_error.ue_error_type = mce_err->u.ue_error_type; + break; + case MCE_ERROR_TYPE_SLB: + mce->u.slb_error.slb_error_type = mce_err->u.slb_error_type; + break; + case MCE_ERROR_TYPE_ERAT: + mce->u.erat_error.erat_error_type = mce_err->u.erat_error_type; + break; + case MCE_ERROR_TYPE_TLB: + mce->u.tlb_error.tlb_error_type = mce_err->u.tlb_error_type; + break; + case MCE_ERROR_TYPE_USER: + mce->u.user_error.user_error_type = mce_err->u.user_error_type; + break; + case MCE_ERROR_TYPE_RA: + mce->u.ra_error.ra_error_type = mce_err->u.ra_error_type; + break; + case MCE_ERROR_TYPE_LINK: + mce->u.link_error.link_error_type = mce_err->u.link_error_type; + break; + case MCE_ERROR_TYPE_UNKNOWN: + default: + break; + } +} + +void mce_irq_work_queue(void) +{ + /* Raise decrementer interrupt */ + arch_irq_work_raise(); + set_mce_pending_irq_work(); +} + +/* + * Decode and save high level MCE information into per cpu buffer which + * is an array of machine_check_event structure. + */ +void save_mce_event(struct pt_regs *regs, long handled, + struct mce_error_info *mce_err, + uint64_t nip, uint64_t addr, uint64_t phys_addr) +{ + int index = local_paca->mce_info->mce_nest_count++; + struct machine_check_event *mce; + + mce = &local_paca->mce_info->mce_event[index]; + /* + * Return if we don't have enough space to log mce event. + * mce_nest_count may go beyond MAX_MC_EVT but that's ok, + * the check below will stop buffer overrun. + */ + if (index >= MAX_MC_EVT) + return; + + /* Populate generic machine check info */ + mce->version = MCE_V1; + mce->srr0 = nip; + mce->srr1 = regs->msr; + mce->gpr3 = regs->gpr[3]; + mce->in_use = 1; + mce->cpu = get_paca()->paca_index; + + /* Mark it recovered if we have handled it and MSR(RI=1). */ + if (handled && (regs->msr & MSR_RI)) + mce->disposition = MCE_DISPOSITION_RECOVERED; + else + mce->disposition = MCE_DISPOSITION_NOT_RECOVERED; + + mce->initiator = mce_err->initiator; + mce->severity = mce_err->severity; + mce->sync_error = mce_err->sync_error; + mce->error_class = mce_err->error_class; + + /* + * Populate the mce error_type and type-specific error_type. + */ + mce_set_error_info(mce, mce_err); + if (mce->error_type == MCE_ERROR_TYPE_UE) + mce->u.ue_error.ignore_event = mce_err->ignore_event; + + if (!addr) + return; + + if (mce->error_type == MCE_ERROR_TYPE_TLB) { + mce->u.tlb_error.effective_address_provided = true; + mce->u.tlb_error.effective_address = addr; + } else if (mce->error_type == MCE_ERROR_TYPE_SLB) { + mce->u.slb_error.effective_address_provided = true; + mce->u.slb_error.effective_address = addr; + } else if (mce->error_type == MCE_ERROR_TYPE_ERAT) { + mce->u.erat_error.effective_address_provided = true; + mce->u.erat_error.effective_address = addr; + } else if (mce->error_type == MCE_ERROR_TYPE_USER) { + mce->u.user_error.effective_address_provided = true; + mce->u.user_error.effective_address = addr; + } else if (mce->error_type == MCE_ERROR_TYPE_RA) { + mce->u.ra_error.effective_address_provided = true; + mce->u.ra_error.effective_address = addr; + } else if (mce->error_type == MCE_ERROR_TYPE_LINK) { + mce->u.link_error.effective_address_provided = true; + mce->u.link_error.effective_address = addr; + } else if (mce->error_type == MCE_ERROR_TYPE_UE) { + mce->u.ue_error.effective_address_provided = true; + mce->u.ue_error.effective_address = addr; + if (phys_addr != ULONG_MAX) { + mce->u.ue_error.physical_address_provided = true; + mce->u.ue_error.physical_address = phys_addr; + machine_check_ue_event(mce); + } + } + return; +} + +/* + * get_mce_event: + * mce Pointer to machine_check_event structure to be filled. + * release Flag to indicate whether to free the event slot or not. + * 0 <= do not release the mce event. Caller will invoke + * release_mce_event() once event has been consumed. + * 1 <= release the slot. + * + * return 1 = success + * 0 = failure + * + * get_mce_event() will be called by platform specific machine check + * handle routine and in KVM. + * When we call get_mce_event(), we are still in interrupt context and + * preemption will not be scheduled until ret_from_expect() routine + * is called. + */ +int get_mce_event(struct machine_check_event *mce, bool release) +{ + int index = local_paca->mce_info->mce_nest_count - 1; + struct machine_check_event *mc_evt; + int ret = 0; + + /* Sanity check */ + if (index < 0) + return ret; + + /* Check if we have MCE info to process. */ + if (index < MAX_MC_EVT) { + mc_evt = &local_paca->mce_info->mce_event[index]; + /* Copy the event structure and release the original */ + if (mce) + *mce = *mc_evt; + if (release) + mc_evt->in_use = 0; + ret = 1; + } + /* Decrement the count to free the slot. */ + if (release) + local_paca->mce_info->mce_nest_count--; + + return ret; +} + +void release_mce_event(void) +{ + get_mce_event(NULL, true); +} + +static void machine_check_ue_work(void) +{ + schedule_work(&mce_ue_event_work); +} + +/* + * Queue up the MCE event which then can be handled later. + */ +static void machine_check_ue_event(struct machine_check_event *evt) +{ + int index; + + index = local_paca->mce_info->mce_ue_count++; + /* If queue is full, just return for now. */ + if (index >= MAX_MC_EVT) { + local_paca->mce_info->mce_ue_count--; + return; + } + memcpy(&local_paca->mce_info->mce_ue_event_queue[index], + evt, sizeof(*evt)); + + /* Queue work to process this event later. */ + mce_irq_work_queue(); +} + +/* + * Queue up the MCE event which then can be handled later. + */ +void machine_check_queue_event(void) +{ + int index; + struct machine_check_event evt; + + if (!get_mce_event(&evt, MCE_EVENT_RELEASE)) + return; + + index = local_paca->mce_info->mce_queue_count++; + /* If queue is full, just return for now. */ + if (index >= MAX_MC_EVT) { + local_paca->mce_info->mce_queue_count--; + return; + } + memcpy(&local_paca->mce_info->mce_event_queue[index], + &evt, sizeof(evt)); + + mce_irq_work_queue(); +} + +void mce_common_process_ue(struct pt_regs *regs, + struct mce_error_info *mce_err) +{ + const struct exception_table_entry *entry; + + entry = search_kernel_exception_table(regs->nip); + if (entry) { + mce_err->ignore_event = true; + regs_set_return_ip(regs, extable_fixup(entry)); + } +} + +/* + * process pending MCE event from the mce event queue. This function will be + * called during syscall exit. + */ +static void machine_process_ue_event(struct work_struct *work) +{ + int index; + struct machine_check_event *evt; + + while (local_paca->mce_info->mce_ue_count > 0) { + index = local_paca->mce_info->mce_ue_count - 1; + evt = &local_paca->mce_info->mce_ue_event_queue[index]; + blocking_notifier_call_chain(&mce_notifier_list, 0, evt); +#ifdef CONFIG_MEMORY_FAILURE + /* + * This should probably queued elsewhere, but + * oh! well + * + * Don't report this machine check because the caller has a + * asked us to ignore the event, it has a fixup handler which + * will do the appropriate error handling and reporting. + */ + if (evt->error_type == MCE_ERROR_TYPE_UE) { + if (evt->u.ue_error.ignore_event) { + local_paca->mce_info->mce_ue_count--; + continue; + } + + if (evt->u.ue_error.physical_address_provided) { + unsigned long pfn; + + pfn = evt->u.ue_error.physical_address >> + PAGE_SHIFT; + memory_failure(pfn, 0); + } else + pr_warn("Failed to identify bad address from " + "where the uncorrectable error (UE) " + "was generated\n"); + } +#endif + local_paca->mce_info->mce_ue_count--; + } +} +/* + * process pending MCE event from the mce event queue. This function will be + * called during syscall exit. + */ +static void machine_check_process_queued_event(void) +{ + int index; + struct machine_check_event *evt; + + add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); + + /* + * For now just print it to console. + * TODO: log this error event to FSP or nvram. + */ + while (local_paca->mce_info->mce_queue_count > 0) { + index = local_paca->mce_info->mce_queue_count - 1; + evt = &local_paca->mce_info->mce_event_queue[index]; + + if (evt->error_type == MCE_ERROR_TYPE_UE && + evt->u.ue_error.ignore_event) { + local_paca->mce_info->mce_queue_count--; + continue; + } + machine_check_print_event_info(evt, false, false); + local_paca->mce_info->mce_queue_count--; + } +} + +void set_mce_pending_irq_work(void) +{ + local_paca->mce_pending_irq_work = 1; +} + +void clear_mce_pending_irq_work(void) +{ + local_paca->mce_pending_irq_work = 0; +} + +void mce_run_irq_context_handlers(void) +{ + if (unlikely(local_paca->mce_pending_irq_work)) { + if (ppc_md.machine_check_log_err) + ppc_md.machine_check_log_err(); + machine_check_process_queued_event(); + machine_check_ue_work(); + clear_mce_pending_irq_work(); + } +} + +void machine_check_print_event_info(struct machine_check_event *evt, + bool user_mode, bool in_guest) +{ + const char *level, *sevstr, *subtype, *err_type, *initiator; + uint64_t ea = 0, pa = 0; + int n = 0; + char dar_str[50]; + char pa_str[50]; + static const char *mc_ue_types[] = { + "Indeterminate", + "Instruction fetch", + "Page table walk ifetch", + "Load/Store", + "Page table walk Load/Store", + }; + static const char *mc_slb_types[] = { + "Indeterminate", + "Parity", + "Multihit", + }; + static const char *mc_erat_types[] = { + "Indeterminate", + "Parity", + "Multihit", + }; + static const char *mc_tlb_types[] = { + "Indeterminate", + "Parity", + "Multihit", + }; + static const char *mc_user_types[] = { + "Indeterminate", + "tlbie(l) invalid", + "scv invalid", + }; + static const char *mc_ra_types[] = { + "Indeterminate", + "Instruction fetch (bad)", + "Instruction fetch (foreign/control memory)", + "Page table walk ifetch (bad)", + "Page table walk ifetch (foreign/control memory)", + "Load (bad)", + "Store (bad)", + "Page table walk Load/Store (bad)", + "Page table walk Load/Store (foreign/control memory)", + "Load/Store (foreign/control memory)", + }; + static const char *mc_link_types[] = { + "Indeterminate", + "Instruction fetch (timeout)", + "Page table walk ifetch (timeout)", + "Load (timeout)", + "Store (timeout)", + "Page table walk Load/Store (timeout)", + }; + static const char *mc_error_class[] = { + "Unknown", + "Hardware error", + "Probable Hardware error (some chance of software cause)", + "Software error", + "Probable Software error (some chance of hardware cause)", + }; + + /* Print things out */ + if (evt->version != MCE_V1) { + pr_err("Machine Check Exception, Unknown event version %d !\n", + evt->version); + return; + } + switch (evt->severity) { + case MCE_SEV_NO_ERROR: + level = KERN_INFO; + sevstr = "Harmless"; + break; + case MCE_SEV_WARNING: + level = KERN_WARNING; + sevstr = "Warning"; + break; + case MCE_SEV_SEVERE: + level = KERN_ERR; + sevstr = "Severe"; + break; + case MCE_SEV_FATAL: + default: + level = KERN_ERR; + sevstr = "Fatal"; + break; + } + + switch(evt->initiator) { + case MCE_INITIATOR_CPU: + initiator = "CPU"; + break; + case MCE_INITIATOR_PCI: + initiator = "PCI"; + break; + case MCE_INITIATOR_ISA: + initiator = "ISA"; + break; + case MCE_INITIATOR_MEMORY: + initiator = "Memory"; + break; + case MCE_INITIATOR_POWERMGM: + initiator = "Power Management"; + break; + case MCE_INITIATOR_UNKNOWN: + default: + initiator = "Unknown"; + break; + } + + switch (evt->error_type) { + case MCE_ERROR_TYPE_UE: + err_type = "UE"; + subtype = evt->u.ue_error.ue_error_type < + ARRAY_SIZE(mc_ue_types) ? + mc_ue_types[evt->u.ue_error.ue_error_type] + : "Unknown"; + if (evt->u.ue_error.effective_address_provided) + ea = evt->u.ue_error.effective_address; + if (evt->u.ue_error.physical_address_provided) + pa = evt->u.ue_error.physical_address; + break; + case MCE_ERROR_TYPE_SLB: + err_type = "SLB"; + subtype = evt->u.slb_error.slb_error_type < + ARRAY_SIZE(mc_slb_types) ? + mc_slb_types[evt->u.slb_error.slb_error_type] + : "Unknown"; + if (evt->u.slb_error.effective_address_provided) + ea = evt->u.slb_error.effective_address; + break; + case MCE_ERROR_TYPE_ERAT: + err_type = "ERAT"; + subtype = evt->u.erat_error.erat_error_type < + ARRAY_SIZE(mc_erat_types) ? + mc_erat_types[evt->u.erat_error.erat_error_type] + : "Unknown"; + if (evt->u.erat_error.effective_address_provided) + ea = evt->u.erat_error.effective_address; + break; + case MCE_ERROR_TYPE_TLB: + err_type = "TLB"; + subtype = evt->u.tlb_error.tlb_error_type < + ARRAY_SIZE(mc_tlb_types) ? + mc_tlb_types[evt->u.tlb_error.tlb_error_type] + : "Unknown"; + if (evt->u.tlb_error.effective_address_provided) + ea = evt->u.tlb_error.effective_address; + break; + case MCE_ERROR_TYPE_USER: + err_type = "User"; + subtype = evt->u.user_error.user_error_type < + ARRAY_SIZE(mc_user_types) ? + mc_user_types[evt->u.user_error.user_error_type] + : "Unknown"; + if (evt->u.user_error.effective_address_provided) + ea = evt->u.user_error.effective_address; + break; + case MCE_ERROR_TYPE_RA: + err_type = "Real address"; + subtype = evt->u.ra_error.ra_error_type < + ARRAY_SIZE(mc_ra_types) ? + mc_ra_types[evt->u.ra_error.ra_error_type] + : "Unknown"; + if (evt->u.ra_error.effective_address_provided) + ea = evt->u.ra_error.effective_address; + break; + case MCE_ERROR_TYPE_LINK: + err_type = "Link"; + subtype = evt->u.link_error.link_error_type < + ARRAY_SIZE(mc_link_types) ? + mc_link_types[evt->u.link_error.link_error_type] + : "Unknown"; + if (evt->u.link_error.effective_address_provided) + ea = evt->u.link_error.effective_address; + break; + case MCE_ERROR_TYPE_DCACHE: + err_type = "D-Cache"; + subtype = "Unknown"; + break; + case MCE_ERROR_TYPE_ICACHE: + err_type = "I-Cache"; + subtype = "Unknown"; + break; + default: + case MCE_ERROR_TYPE_UNKNOWN: + err_type = "Unknown"; + subtype = ""; + break; + } + + dar_str[0] = pa_str[0] = '\0'; + if (ea && evt->srr0 != ea) { + /* Load/Store address */ + n = sprintf(dar_str, "DAR: %016llx ", ea); + if (pa) + sprintf(dar_str + n, "paddr: %016llx ", pa); + } else if (pa) { + sprintf(pa_str, " paddr: %016llx", pa); + } + + printk("%sMCE: CPU%d: machine check (%s) %s %s %s %s[%s]\n", + level, evt->cpu, sevstr, in_guest ? "Guest" : "", + err_type, subtype, dar_str, + evt->disposition == MCE_DISPOSITION_RECOVERED ? + "Recovered" : "Not recovered"); + + if (in_guest || user_mode) { + printk("%sMCE: CPU%d: PID: %d Comm: %s %sNIP: [%016llx]%s\n", + level, evt->cpu, current->pid, current->comm, + in_guest ? "Guest " : "", evt->srr0, pa_str); + } else { + printk("%sMCE: CPU%d: NIP: [%016llx] %pS%s\n", + level, evt->cpu, evt->srr0, (void *)evt->srr0, pa_str); + } + + printk("%sMCE: CPU%d: Initiator %s\n", level, evt->cpu, initiator); + + subtype = evt->error_class < ARRAY_SIZE(mc_error_class) ? + mc_error_class[evt->error_class] : "Unknown"; + printk("%sMCE: CPU%d: %s\n", level, evt->cpu, subtype); + +#ifdef CONFIG_PPC_64S_HASH_MMU + /* Display faulty slb contents for SLB errors. */ + if (evt->error_type == MCE_ERROR_TYPE_SLB && !in_guest) + slb_dump_contents(local_paca->mce_faulty_slbs); +#endif +} +EXPORT_SYMBOL_GPL(machine_check_print_event_info); + +/* + * This function is called in real mode. Strictly no printk's please. + * + * regs->nip and regs->msr contains srr0 and ssr1. + */ +DEFINE_INTERRUPT_HANDLER_NMI(machine_check_early) +{ + long handled = 0; + + hv_nmi_check_nonrecoverable(regs); + + /* + * See if platform is capable of handling machine check. + */ + if (ppc_md.machine_check_early) + handled = ppc_md.machine_check_early(regs); + + return handled; +} + +/* Possible meanings for HMER_DEBUG_TRIG bit being set on POWER9 */ +static enum { + DTRIG_UNKNOWN, + DTRIG_VECTOR_CI, /* need to emulate vector CI load instr */ + DTRIG_SUSPEND_ESCAPE, /* need to escape from TM suspend mode */ +} hmer_debug_trig_function; + +static int init_debug_trig_function(void) +{ + int pvr; + struct device_node *cpun; + struct property *prop = NULL; + const char *str; + + /* First look in the device tree */ + preempt_disable(); + cpun = of_get_cpu_node(smp_processor_id(), NULL); + if (cpun) { + of_property_for_each_string(cpun, "ibm,hmi-special-triggers", + prop, str) { + if (strcmp(str, "bit17-vector-ci-load") == 0) + hmer_debug_trig_function = DTRIG_VECTOR_CI; + else if (strcmp(str, "bit17-tm-suspend-escape") == 0) + hmer_debug_trig_function = DTRIG_SUSPEND_ESCAPE; + } + of_node_put(cpun); + } + preempt_enable(); + + /* If we found the property, don't look at PVR */ + if (prop) + goto out; + + pvr = mfspr(SPRN_PVR); + /* Check for POWER9 Nimbus (scale-out) */ + if ((PVR_VER(pvr) == PVR_POWER9) && (pvr & 0xe000) == 0) { + /* DD2.2 and later */ + if ((pvr & 0xfff) >= 0x202) + hmer_debug_trig_function = DTRIG_SUSPEND_ESCAPE; + /* DD2.0 and DD2.1 - used for vector CI load emulation */ + else if ((pvr & 0xfff) >= 0x200) + hmer_debug_trig_function = DTRIG_VECTOR_CI; + } + + out: + switch (hmer_debug_trig_function) { + case DTRIG_VECTOR_CI: + pr_debug("HMI debug trigger used for vector CI load\n"); + break; + case DTRIG_SUSPEND_ESCAPE: + pr_debug("HMI debug trigger used for TM suspend escape\n"); + break; + default: + break; + } + return 0; +} +__initcall(init_debug_trig_function); + +/* + * Handle HMIs that occur as a result of a debug trigger. + * Return values: + * -1 means this is not a HMI cause that we know about + * 0 means no further handling is required + * 1 means further handling is required + */ +long hmi_handle_debugtrig(struct pt_regs *regs) +{ + unsigned long hmer = mfspr(SPRN_HMER); + long ret = 0; + + /* HMER_DEBUG_TRIG bit is used for various workarounds on P9 */ + if (!((hmer & HMER_DEBUG_TRIG) + && hmer_debug_trig_function != DTRIG_UNKNOWN)) + return -1; + + hmer &= ~HMER_DEBUG_TRIG; + /* HMER is a write-AND register */ + mtspr(SPRN_HMER, ~HMER_DEBUG_TRIG); + + switch (hmer_debug_trig_function) { + case DTRIG_VECTOR_CI: + /* + * Now to avoid problems with soft-disable we + * only do the emulation if we are coming from + * host user space + */ + if (regs && user_mode(regs)) + ret = local_paca->hmi_p9_special_emu = 1; + + break; + + default: + break; + } + + /* + * See if any other HMI causes remain to be handled + */ + if (hmer & mfspr(SPRN_HMEER)) + return -1; + + return ret; +} + +/* + * Return values: + */ +DEFINE_INTERRUPT_HANDLER_NMI(hmi_exception_realmode) +{ + int ret; + + local_paca->hmi_irqs++; + + ret = hmi_handle_debugtrig(regs); + if (ret >= 0) + return ret; + + wait_for_subcore_guest_exit(); + + if (ppc_md.hmi_exception_early) + ppc_md.hmi_exception_early(regs); + + wait_for_tb_resync(); + + return 1; +} + +void __init mce_init(void) +{ + struct mce_info *mce_info; + u64 limit; + int i; + + limit = min(ppc64_bolted_size(), ppc64_rma_size); + for_each_possible_cpu(i) { + mce_info = memblock_alloc_try_nid(sizeof(*mce_info), + __alignof__(*mce_info), + MEMBLOCK_LOW_LIMIT, + limit, early_cpu_to_node(i)); + if (!mce_info) + goto err; + paca_ptrs[i]->mce_info = mce_info; + } + return; +err: + panic("Failed to allocate memory for MCE event data\n"); +} |