// SPDX-License-Identifier: GPL-2.0-only /* * File: mca_drv.c * Purpose: Generic MCA handling layer * * Copyright (C) 2004 FUJITSU LIMITED * Copyright (C) 2004 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> * Copyright (C) 2005 Silicon Graphics, Inc * Copyright (C) 2005 Keith Owens <kaos@sgi.com> * Copyright (C) 2006 Russ Anderson <rja@sgi.com> */ #include <linux/types.h> #include <linux/init.h> #include <linux/sched.h> #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/kallsyms.h> #include <linux/memblock.h> #include <linux/acpi.h> #include <linux/timer.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/smp.h> #include <linux/workqueue.h> #include <linux/mm.h> #include <linux/slab.h> #include <asm/delay.h> #include <asm/page.h> #include <asm/ptrace.h> #include <asm/sal.h> #include <asm/mca.h> #include <asm/irq.h> #include <asm/hw_irq.h> #include "mca_drv.h" /* max size of SAL error record (default) */ static int sal_rec_max = 10000; /* from mca_drv_asm.S */ extern void *mca_handler_bhhook(void); static DEFINE_SPINLOCK(mca_bh_lock); typedef enum { MCA_IS_LOCAL = 0, MCA_IS_GLOBAL = 1 } mca_type_t; #define MAX_PAGE_ISOLATE 1024 static struct page *page_isolate[MAX_PAGE_ISOLATE]; static int num_page_isolate = 0; typedef enum { ISOLATE_NG, ISOLATE_OK, ISOLATE_NONE } isolate_status_t; typedef enum { MCA_NOT_RECOVERED = 0, MCA_RECOVERED = 1 } recovery_status_t; /* * This pool keeps pointers to the section part of SAL error record */ static struct { slidx_list_t *buffer; /* section pointer list pool */ int cur_idx; /* Current index of section pointer list pool */ int max_idx; /* Maximum index of section pointer list pool */ } slidx_pool; static int fatal_mca(const char *fmt, ...) { va_list args; char buf[256]; va_start(args, fmt); vsnprintf(buf, sizeof(buf), fmt, args); va_end(args); ia64_mca_printk(KERN_ALERT "MCA: %s\n", buf); return MCA_NOT_RECOVERED; } static int mca_recovered(const char *fmt, ...) { va_list args; char buf[256]; va_start(args, fmt); vsnprintf(buf, sizeof(buf), fmt, args); va_end(args); ia64_mca_printk(KERN_INFO "MCA: %s\n", buf); return MCA_RECOVERED; } /** * mca_page_isolate - isolate a poisoned page in order not to use it later * @paddr: poisoned memory location * * Return value: * one of isolate_status_t, ISOLATE_OK/NG/NONE. */ static isolate_status_t mca_page_isolate(unsigned long paddr) { int i; struct page *p; /* whether physical address is valid or not */ if (!ia64_phys_addr_valid(paddr)) return ISOLATE_NONE; if (!pfn_valid(paddr >> PAGE_SHIFT)) return ISOLATE_NONE; /* convert physical address to physical page number */ p = pfn_to_page(paddr>>PAGE_SHIFT); /* check whether a page number have been already registered or not */ for (i = 0; i < num_page_isolate; i++) if (page_isolate[i] == p) return ISOLATE_OK; /* already listed */ /* limitation check */ if (num_page_isolate == MAX_PAGE_ISOLATE) return ISOLATE_NG; /* kick pages having attribute 'SLAB' or 'Reserved' */ if (PageSlab(p) || PageReserved(p)) return ISOLATE_NG; /* add attribute 'Reserved' and register the page */ get_page(p); SetPageReserved(p); page_isolate[num_page_isolate++] = p; return ISOLATE_OK; } /** * mca_hanlder_bh - Kill the process which occurred memory read error * @paddr: poisoned address received from MCA Handler */ void mca_handler_bh(unsigned long paddr, void *iip, unsigned long ipsr) { ia64_mlogbuf_dump(); printk(KERN_ERR "OS_MCA: process [cpu %d, pid: %d, uid: %d, " "iip: %p, psr: 0x%lx,paddr: 0x%lx](%s) encounters MCA.\n", raw_smp_processor_id(), current->pid, from_kuid(&init_user_ns, current_uid()), iip, ipsr, paddr, current->comm); spin_lock(&mca_bh_lock); switch (mca_page_isolate(paddr)) { case ISOLATE_OK: printk(KERN_DEBUG "Page isolation: ( %lx ) success.\n", paddr); break; case ISOLATE_NG: printk(KERN_CRIT "Page isolation: ( %lx ) failure.\n", paddr); break; default: break; } spin_unlock(&mca_bh_lock); /* This process is about to be killed itself */ make_task_dead(SIGKILL); } /** * mca_make_peidx - Make index of processor error section * @slpi: pointer to record of processor error section * @peidx: pointer to index of processor error section */ static void mca_make_peidx(sal_log_processor_info_t *slpi, peidx_table_t *peidx) { /* * calculate the start address of * "struct cpuid_info" and "sal_processor_static_info_t". */ u64 total_check_num = slpi->valid.num_cache_check + slpi->valid.num_tlb_check + slpi->valid.num_bus_check + slpi->valid.num_reg_file_check + slpi->valid.num_ms_check; u64 head_size = sizeof(sal_log_mod_error_info_t) * total_check_num + sizeof(sal_log_processor_info_t); u64 mid_size = slpi->valid.cpuid_info * sizeof(struct sal_cpuid_info); peidx_head(peidx) = slpi; peidx_mid(peidx) = (struct sal_cpuid_info *) (slpi->valid.cpuid_info ? ((char*)slpi + head_size) : NULL); peidx_bottom(peidx) = (sal_processor_static_info_t *) (slpi->valid.psi_static_struct ? ((char*)slpi + head_size + mid_size) : NULL); } /** * mca_make_slidx - Make index of SAL error record * @buffer: pointer to SAL error record * @slidx: pointer to index of SAL error record * * Return value: * 1 if record has platform error / 0 if not */ #define LOG_INDEX_ADD_SECT_PTR(sect, ptr) \ {slidx_list_t *hl = &slidx_pool.buffer[slidx_pool.cur_idx]; \ hl->hdr = ptr; \ list_add(&hl->list, &(sect)); \ slidx_pool.cur_idx = (slidx_pool.cur_idx + 1)%slidx_pool.max_idx; } static int mca_make_slidx(void *buffer, slidx_table_t *slidx) { int platform_err = 0; int record_len = ((sal_log_record_header_t*)buffer)->len; u32 ercd_pos; int sects; sal_log_section_hdr_t *sp; /* * Initialize index referring current record */ INIT_LIST_HEAD(&(slidx->proc_err)); INIT_LIST_HEAD(&(slidx->mem_dev_err)); INIT_LIST_HEAD(&(slidx->sel_dev_err)); INIT_LIST_HEAD(&(slidx->pci_bus_err)); INIT_LIST_HEAD(&(slidx->smbios_dev_err)); INIT_LIST_HEAD(&(slidx->pci_comp_err)); INIT_LIST_HEAD(&(slidx->plat_specific_err)); INIT_LIST_HEAD(&(slidx->host_ctlr_err)); INIT_LIST_HEAD(&(slidx->plat_bus_err)); INIT_LIST_HEAD(&(slidx->unsupported)); /* * Extract a Record Header */ slidx->header = buffer; /* * Extract each section records * (arranged from "int ia64_log_platform_info_print()") */ for (ercd_pos = sizeof(sal_log_record_header_t), sects = 0; ercd_pos < record_len; ercd_pos += sp->len, sects++) { sp = (sal_log_section_hdr_t *)((char*)buffer + ercd_pos); if (!efi_guidcmp(sp->guid, SAL_PROC_DEV_ERR_SECT_GUID)) { LOG_INDEX_ADD_SECT_PTR(slidx->proc_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_MEM_DEV_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->mem_dev_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_SEL_DEV_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->sel_dev_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_PCI_BUS_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->pci_bus_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_SMBIOS_DEV_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->smbios_dev_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_PCI_COMP_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->pci_comp_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_SPECIFIC_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->plat_specific_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_HOST_CTLR_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->host_ctlr_err, sp); } else if (!efi_guidcmp(sp->guid, SAL_PLAT_BUS_ERR_SECT_GUID)) { platform_err = 1; LOG_INDEX_ADD_SECT_PTR(slidx->plat_bus_err, sp); } else { LOG_INDEX_ADD_SECT_PTR(slidx->unsupported, sp); } } slidx->n_sections = sects; return platform_err; } /** * init_record_index_pools - Initialize pool of lists for SAL record index * * Return value: * 0 on Success / -ENOMEM on Failure */ static int init_record_index_pools(void) { int i; int rec_max_size; /* Maximum size of SAL error records */ int sect_min_size; /* Minimum size of SAL error sections */ /* minimum size table of each section */ static int sal_log_sect_min_sizes[] = { sizeof(sal_log_processor_info_t) + sizeof(sal_processor_static_info_t), sizeof(sal_log_mem_dev_err_info_t), sizeof(sal_log_sel_dev_err_info_t), sizeof(sal_log_pci_bus_err_info_t), sizeof(sal_log_smbios_dev_err_info_t), sizeof(sal_log_pci_comp_err_info_t), sizeof(sal_log_plat_specific_err_info_t), sizeof(sal_log_host_ctlr_err_info_t), sizeof(sal_log_plat_bus_err_info_t), }; /* * MCA handler cannot allocate new memory on flight, * so we preallocate enough memory to handle a SAL record. * * Initialize a handling set of slidx_pool: * 1. Pick up the max size of SAL error records * 2. Pick up the min size of SAL error sections * 3. Allocate the pool as enough to 2 SAL records * (now we can estimate the maxinum of section in a record.) */ /* - 1 - */ rec_max_size = sal_rec_max; /* - 2 - */ sect_min_size = sal_log_sect_min_sizes[0]; for (i = 1; i < ARRAY_SIZE(sal_log_sect_min_sizes); i++) if (sect_min_size > sal_log_sect_min_sizes[i]) sect_min_size = sal_log_sect_min_sizes[i]; /* - 3 - */ slidx_pool.max_idx = (rec_max_size/sect_min_size) * 2 + 1; slidx_pool.buffer = kmalloc_array(slidx_pool.max_idx, sizeof(slidx_list_t), GFP_KERNEL); return slidx_pool.buffer ? 0 : -ENOMEM; } /***************************************************************************** * Recovery functions * *****************************************************************************/ /** * is_mca_global - Check whether this MCA is global or not * @peidx: pointer of index of processor error section * @pbci: pointer to pal_bus_check_info_t * @sos: pointer to hand off struct between SAL and OS * * Return value: * MCA_IS_LOCAL / MCA_IS_GLOBAL */ static mca_type_t is_mca_global(peidx_table_t *peidx, pal_bus_check_info_t *pbci, struct ia64_sal_os_state *sos) { pal_processor_state_info_t *psp = (pal_processor_state_info_t*)peidx_psp(peidx); /* * PAL can request a rendezvous, if the MCA has a global scope. * If "rz_always" flag is set, SAL requests MCA rendezvous * in spite of global MCA. * Therefore it is local MCA when rendezvous has not been requested. * Failed to rendezvous, the system must be down. */ switch (sos->rv_rc) { case -1: /* SAL rendezvous unsuccessful */ return MCA_IS_GLOBAL; case 0: /* SAL rendezvous not required */ return MCA_IS_LOCAL; case 1: /* SAL rendezvous successful int */ case 2: /* SAL rendezvous successful int with init */ default: break; } /* * If One or more Cache/TLB/Reg_File/Uarch_Check is here, * it would be a local MCA. (i.e. processor internal error) */ if (psp->tc || psp->cc || psp->rc || psp->uc) return MCA_IS_LOCAL; /* * Bus_Check structure with Bus_Check.ib (internal bus error) flag set * would be a global MCA. (e.g. a system bus address parity error) */ if (!pbci || pbci->ib) return MCA_IS_GLOBAL; /* * Bus_Check structure with Bus_Check.eb (external bus error) flag set * could be either a local MCA or a global MCA. * * Referring Bus_Check.bsi: * 0: Unknown/unclassified * 1: BERR# * 2: BINIT# * 3: Hard Fail * (FIXME: Are these SGI specific or generic bsi values?) */ if (pbci->eb) switch (pbci->bsi) { case 0: /* e.g. a load from poisoned memory */ return MCA_IS_LOCAL; case 1: case 2: case 3: return MCA_IS_GLOBAL; } return MCA_IS_GLOBAL; } /** * get_target_identifier - Get the valid Cache or Bus check target identifier. * @peidx: pointer of index of processor error section * * Return value: * target address on Success / 0 on Failure */ static u64 get_target_identifier(peidx_table_t *peidx) { u64 target_address = 0; sal_log_mod_error_info_t *smei; pal_cache_check_info_t *pcci; int i, level = 9; /* * Look through the cache checks for a valid target identifier * If more than one valid target identifier, return the one * with the lowest cache level. */ for (i = 0; i < peidx_cache_check_num(peidx); i++) { smei = (sal_log_mod_error_info_t *)peidx_cache_check(peidx, i); if (smei->valid.target_identifier && smei->target_identifier) { pcci = (pal_cache_check_info_t *)&(smei->check_info); if (!target_address || (pcci->level < level)) { target_address = smei->target_identifier; level = pcci->level; continue; } } } if (target_address) return target_address; /* * Look at the bus check for a valid target identifier */ smei = peidx_bus_check(peidx, 0); if (smei && smei->valid.target_identifier) return smei->target_identifier; return 0; } /** * recover_from_read_error - Try to recover the errors which type are "read"s. * @slidx: pointer of index of SAL error record * @peidx: pointer of index of processor error section * @pbci: pointer of pal_bus_check_info * @sos: pointer to hand off struct between SAL and OS * * Return value: * 1 on Success / 0 on Failure */ static int recover_from_read_error(slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_check_info_t *pbci, struct ia64_sal_os_state *sos) { u64 target_identifier; struct pal_min_state_area *pmsa; struct ia64_psr *psr1, *psr2; ia64_fptr_t *mca_hdlr_bh = (ia64_fptr_t*)mca_handler_bhhook; /* Is target address valid? */ target_identifier = get_target_identifier(peidx); if (!target_identifier) return fatal_mca("target address not valid"); /* * cpu read or memory-mapped io read * * offending process affected process OS MCA do * kernel mode kernel mode down system * kernel mode user mode kill the process * user mode kernel mode down system (*) * user mode user mode kill the process * * (*) You could terminate offending user-mode process * if (pbci->pv && pbci->pl != 0) *and* if you sure * the process not have any locks of kernel. */ /* Is minstate valid? */ if (!peidx_bottom(peidx) || !(peidx_bottom(peidx)->valid.minstate)) return fatal_mca("minstate not valid"); psr1 =(struct ia64_psr *)&(peidx_minstate_area(peidx)->pmsa_ipsr); psr2 =(struct ia64_psr *)&(peidx_minstate_area(peidx)->pmsa_xpsr); /* * Check the privilege level of interrupted context. * If it is user-mode, then terminate affected process. */ pmsa = sos->pal_min_state; if (psr1->cpl != 0 || ((psr2->cpl != 0) && mca_recover_range(pmsa->pmsa_iip))) { /* * setup for resume to bottom half of MCA, * "mca_handler_bhhook" */ /* pass to bhhook as argument (gr8, ...) */ pmsa->pmsa_gr[8-1] = target_identifier; pmsa->pmsa_gr[9-1] = pmsa->pmsa_iip; pmsa->pmsa_gr[10-1] = pmsa->pmsa_ipsr; /* set interrupted return address (but no use) */ pmsa->pmsa_br0 = pmsa->pmsa_iip; /* change resume address to bottom half */ pmsa->pmsa_iip = mca_hdlr_bh->fp; pmsa->pmsa_gr[1-1] = mca_hdlr_bh->gp; /* set cpl with kernel mode */ psr2 = (struct ia64_psr *)&pmsa->pmsa_ipsr; psr2->cpl = 0; psr2->ri = 0; psr2->bn = 1; psr2->i = 0; return mca_recovered("user memory corruption. " "kill affected process - recovered."); } return fatal_mca("kernel context not recovered, iip 0x%lx\n", pmsa->pmsa_iip); } /** * recover_from_platform_error - Recover from platform error. * @slidx: pointer of index of SAL error record * @peidx: pointer of index of processor error section * @pbci: pointer of pal_bus_check_info * @sos: pointer to hand off struct between SAL and OS * * Return value: * 1 on Success / 0 on Failure */ static int recover_from_platform_error(slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_check_info_t *pbci, struct ia64_sal_os_state *sos) { int status = 0; pal_processor_state_info_t *psp = (pal_processor_state_info_t*)peidx_psp(peidx); if (psp->bc && pbci->eb && pbci->bsi == 0) { switch(pbci->type) { case 1: /* partial read */ case 3: /* full line(cpu) read */ case 9: /* I/O space read */ status = recover_from_read_error(slidx, peidx, pbci, sos); break; case 0: /* unknown */ case 2: /* partial write */ case 4: /* full line write */ case 5: /* implicit or explicit write-back operation */ case 6: /* snoop probe */ case 7: /* incoming or outgoing ptc.g */ case 8: /* write coalescing transactions */ case 10: /* I/O space write */ case 11: /* inter-processor interrupt message(IPI) */ case 12: /* interrupt acknowledge or external task priority cycle */ default: break; } } else if (psp->cc && !psp->bc) { /* Cache error */ status = recover_from_read_error(slidx, peidx, pbci, sos); } return status; } /* * recover_from_tlb_check * @peidx: pointer of index of processor error section * * Return value: * 1 on Success / 0 on Failure */ static int recover_from_tlb_check(peidx_table_t *peidx) { sal_log_mod_error_info_t *smei; pal_tlb_check_info_t *ptci; smei = (sal_log_mod_error_info_t *)peidx_tlb_check(peidx, 0); ptci = (pal_tlb_check_info_t *)&(smei->check_info); /* * Look for signature of a duplicate TLB DTC entry, which is * a SW bug and always fatal. */ if (ptci->op == PAL_TLB_CHECK_OP_PURGE && !(ptci->itr || ptci->dtc || ptci->itc)) return fatal_mca("Duplicate TLB entry"); return mca_recovered("TLB check recovered"); } /** * recover_from_processor_error * @platform: whether there are some platform error section or not * @slidx: pointer of index of SAL error record * @peidx: pointer of index of processor error section * @pbci: pointer of pal_bus_check_info * @sos: pointer to hand off struct between SAL and OS * * Return value: * 1 on Success / 0 on Failure */ static int recover_from_processor_error(int platform, slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_check_info_t *pbci, struct ia64_sal_os_state *sos) { pal_processor_state_info_t *psp = (pal_processor_state_info_t*)peidx_psp(peidx); /* * Processor recovery status must key off of the PAL recovery * status in the Processor State Parameter. */ /* * The machine check is corrected. */ if (psp->cm == 1) return mca_recovered("machine check is already corrected."); /* * The error was not contained. Software must be reset. */ if (psp->us || psp->ci == 0) return fatal_mca("error not contained"); /* * Look for recoverable TLB check */ if (psp->tc && !(psp->cc || psp->bc || psp->rc || psp->uc)) return recover_from_tlb_check(peidx); /* * The cache check and bus check bits have four possible states * cc bc * 1 1 Memory error, attempt recovery * 1 0 Cache error, attempt recovery * 0 1 I/O error, attempt recovery * 0 0 Other error type, not recovered */ if (psp->cc == 0 && (psp->bc == 0 || pbci == NULL)) return fatal_mca("No cache or bus check"); /* * Cannot handle more than one bus check. */ if (peidx_bus_check_num(peidx) > 1) return fatal_mca("Too many bus checks"); if (pbci->ib) return fatal_mca("Internal Bus error"); if (pbci->eb && pbci->bsi > 0) return fatal_mca("External bus check fatal status"); /* * This is a local MCA and estimated as a recoverable error. */ if (platform) return recover_from_platform_error(slidx, peidx, pbci, sos); /* * On account of strange SAL error record, we cannot recover. */ return fatal_mca("Strange SAL record"); } /** * mca_try_to_recover - Try to recover from MCA * @rec: pointer to a SAL error record * @sos: pointer to hand off struct between SAL and OS * * Return value: * 1 on Success / 0 on Failure */ static int mca_try_to_recover(void *rec, struct ia64_sal_os_state *sos) { int platform_err; int n_proc_err; slidx_table_t slidx; peidx_table_t peidx; pal_bus_check_info_t pbci; /* Make index of SAL error record */ platform_err = mca_make_slidx(rec, &slidx); /* Count processor error sections */ n_proc_err = slidx_count(&slidx, proc_err); /* Now, OS can recover when there is one processor error section */ if (n_proc_err > 1) return fatal_mca("Too Many Errors"); else if (n_proc_err == 0) /* Weird SAL record ... We can't do anything */ return fatal_mca("Weird SAL record"); /* Make index of processor error section */ mca_make_peidx((sal_log_processor_info_t*) slidx_first_entry(&slidx.proc_err)->hdr, &peidx); /* Extract Processor BUS_CHECK[0] */ *((u64*)&pbci) = peidx_check_info(&peidx, bus_check, 0); /* Check whether MCA is global or not */ if (is_mca_global(&peidx, &pbci, sos)) return fatal_mca("global MCA"); /* Try to recover a processor error */ return recover_from_processor_error(platform_err, &slidx, &peidx, &pbci, sos); } /* * ============================================================================= */ int __init mca_external_handler_init(void) { if (init_record_index_pools()) return -ENOMEM; /* register external mca handlers */ if (ia64_reg_MCA_extension(mca_try_to_recover)) { printk(KERN_ERR "ia64_reg_MCA_extension failed.\n"); kfree(slidx_pool.buffer); return -EFAULT; } return 0; } void __exit mca_external_handler_exit(void) { /* unregister external mca handlers */ ia64_unreg_MCA_extension(); kfree(slidx_pool.buffer); } module_init(mca_external_handler_init); module_exit(mca_external_handler_exit); module_param(sal_rec_max, int, 0644); MODULE_PARM_DESC(sal_rec_max, "Max size of SAL error record"); MODULE_DESCRIPTION("ia64 platform dependent mca handler driver"); MODULE_LICENSE("GPL");