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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/ia64/kernel/mca_drv.c
Initial import
Diffstat (limited to 'arch/ia64/kernel/mca_drv.c')
-rw-r--r--arch/ia64/kernel/mca_drv.c795
1 files changed, 795 insertions, 0 deletions
diff --git a/arch/ia64/kernel/mca_drv.c b/arch/ia64/kernel/mca_drv.c
new file mode 100644
index 000000000..94f8bf777
--- /dev/null
+++ b/arch/ia64/kernel/mca_drv.c
@@ -0,0 +1,795 @@
+/*
+ * 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/bootmem.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/machvec.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 */
+ do_exit(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 < sizeof sal_log_sect_min_sizes/sizeof(size_t); 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(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;
+ pal_min_state_area_t *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");