include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[safe/jmp/linux-2.6] / arch / ia64 / kernel / mca_drv.c
index ab47817..09b4d68 100644 (file)
@@ -3,16 +3,17 @@
  * Purpose:    Generic MCA handling layer
  *
  * Copyright (C) 2004 FUJITSU LIMITED
- * Copyright (C) Hidetoshi Seto (seto.hidetoshi@jp.fujitsu.com)
+ * 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/config.h>
 #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/smp_lock.h>
 #include <linux/bootmem.h>
 #include <linux/acpi.h>
 #include <linux/timer.h>
@@ -21,6 +22,7 @@
 #include <linux/smp.h>
 #include <linux/workqueue.h>
 #include <linux/mm.h>
+#include <linux/slab.h>
 
 #include <asm/delay.h>
 #include <asm/machvec.h>
 /* max size of SAL error record (default) */
 static int sal_rec_max = 10000;
 
-/* from mca.c */
-static ia64_mca_sal_to_os_state_t *sal_to_os_handoff_state;
-static ia64_mca_os_to_sal_state_t *os_to_sal_handoff_state;
-
 /* from mca_drv_asm.S */
 extern void *mca_handler_bhhook(void);
 
@@ -58,10 +56,16 @@ static struct page *page_isolate[MAX_PAGE_ISOLATE];
 static int num_page_isolate = 0;
 
 typedef enum {
-       ISOLATE_NG = 0,
-       ISOLATE_OK = 1
+       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
  */
@@ -71,12 +75,40 @@ static struct {
        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:
- *     ISOLATE_OK / ISOLATE_NG
+ *     one of isolate_status_t, ISOLATE_OK/NG/NONE.
  */
 
 static isolate_status_t
@@ -86,26 +118,30 @@ mca_page_isolate(unsigned long paddr)
        struct page *p;
 
        /* whether physical address is valid or not */
-       if ( !ia64_phys_addr_valid(paddr) ) 
-               return ISOLATE_NG;
+       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 )
+       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 ) 
+       if (num_page_isolate == MAX_PAGE_ISOLATE)
                return ISOLATE_NG;
 
        /* kick pages having attribute 'SLAB' or 'Reserved' */
-       if( PageSlab(p) || PageReserved(p) ) 
+       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;
 
@@ -118,22 +154,29 @@ mca_page_isolate(unsigned long paddr)
  */
 
 void
-mca_handler_bh(unsigned long paddr)
+mca_handler_bh(unsigned long paddr, void *iip, unsigned long ipsr)
 {
-       printk(KERN_DEBUG "OS_MCA: process [pid: %d](%s) encounters MCA.\n",
-               current->pid, current->comm);
+       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, current_uid(),
+               iip, ipsr, paddr, current->comm);
 
        spin_lock(&mca_bh_lock);
-       if (mca_page_isolate(paddr) == ISOLATE_OK) {
+       switch (mca_page_isolate(paddr)) {
+       case ISOLATE_OK:
                printk(KERN_DEBUG "Page isolation: ( %lx ) success.\n", paddr);
-       } else {
-               printk(KERN_DEBUG "Page isolation: ( %lx ) failure.\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 */
-       force_sig(SIGKILL, current);
-       schedule();
+       do_exit(SIGKILL);
 }
 
 /**
@@ -142,10 +185,10 @@ mca_handler_bh(unsigned long paddr)
  * @peidx:     pointer to index of processor error section
  */
 
-static void 
+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".
         */
@@ -167,7 +210,7 @@ mca_make_peidx(sal_log_processor_info_t *slpi, peidx_table_t *peidx)
 }
 
 /**
- * mca_make_slidx -  Make index of SAL error record 
+ * mca_make_slidx -  Make index of SAL error record
  * @buffer:    pointer to SAL error record
  * @slidx:     pointer to index of SAL error record
  *
@@ -175,12 +218,12 @@ mca_make_peidx(sal_log_processor_info_t *slpi, peidx_table_t *peidx)
  *     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; }
+       {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 
+static int
 mca_make_slidx(void *buffer, slidx_table_t *slidx)
 {
        int platform_err = 0;
@@ -217,28 +260,36 @@ mca_make_slidx(void *buffer, slidx_table_t *slidx)
                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)) {
+               } 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)) {
+               } 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)) {
+               } 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)) {
+               } 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)) {
+               } 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)) {
+               } 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)) {
+               } 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)) {
+               } 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 {
@@ -256,15 +307,16 @@ mca_make_slidx(void *buffer, slidx_table_t *slidx)
  * Return value:
  *     0 on Success / -ENOMEM on Failure
  */
-static int 
+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),
+       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),
@@ -297,7 +349,8 @@ init_record_index_pools(void)
 
        /* - 3 - */
        slidx_pool.max_idx = (rec_max_size/sect_min_size) * 2 + 1;
-       slidx_pool.buffer = (slidx_list_t *) kmalloc(slidx_pool.max_idx * sizeof(slidx_list_t), GFP_KERNEL);
+       slidx_pool.buffer = (slidx_list_t *)
+               kmalloc(slidx_pool.max_idx * sizeof(slidx_list_t), GFP_KERNEL);
 
        return slidx_pool.buffer ? 0 : -ENOMEM;
 }
@@ -311,24 +364,27 @@ init_record_index_pools(void)
  * 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)
+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_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 
+        * 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 (sal_to_os_handoff_state->imsto_rendez_state) {
+       switch (sos->rv_rc) {
                case -1: /* SAL rendezvous unsuccessful */
                        return MCA_IS_GLOBAL;
                case  0: /* SAL rendezvous not required */
@@ -379,26 +435,74 @@ is_mca_global(peidx_table_t *peidx, pal_bus_check_info_t *pbci)
 }
 
 /**
+ * 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)
+recover_from_read_error(slidx_table_t *slidx,
+                       peidx_table_t *peidx, pal_bus_check_info_t *pbci,
+                       struct ia64_sal_os_state *sos)
 {
-       sal_log_mod_error_info_t *smei;
+       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? */
-       if (!pbci->tv)
-               return 0;
+       target_identifier = get_target_identifier(peidx);
+       if (!target_identifier)
+               return fatal_mca("target address not valid");
 
        /*
         * cpu read or memory-mapped io read
@@ -414,38 +518,46 @@ recover_from_read_error(slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_chec
         *    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.
         */
-       if (psr1->cpl != 0) {
-               smei = peidx_bus_check(peidx, 0);
-               if (smei->valid.target_identifier) {
-                       /*
-                        *  setup for resume to bottom half of MCA,
-                        * "mca_handler_bhhook"
-                        */
-                       pmsa = (pal_min_state_area_t *)(sal_to_os_handoff_state->pal_min_state | (6ul<<61));
-                       /* pass to bhhook as 1st argument (gr8) */
-                       pmsa->pmsa_gr[8-1] = smei->target_identifier;
-                       /* 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;
-
-                       return 1;
-               }
 
+       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 0;
+       return fatal_mca("kernel context not recovered, iip 0x%lx\n",
+                        pmsa->pmsa_iip);
 }
 
 /**
@@ -453,23 +565,28 @@ recover_from_read_error(slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_chec
  * @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)
+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);
+       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);
+                       status = recover_from_read_error(slidx, peidx, pbci,
+                                                        sos);
                        break;
                case 0: /* unknown */
                case 2: /* partial write */
@@ -480,90 +597,133 @@ recover_from_platform_error(slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_
                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 */
+               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
  */
-/*
- *  Later we try to recover when below all conditions are satisfied.
- *   1. Only one processor error section is exist.
- *   2. BUS_CHECK is exist and the others are not exist.(Except TLB_CHECK)
- *   3. The entry of BUS_CHECK_INFO is 1.
- *   4. "External bus error" flag is set and the others are not set.
- */
 
 static int
-recover_from_processor_error(int platform, slidx_table_t *slidx, peidx_table_t *peidx, pal_bus_check_info_t *pbci)
+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);
+       pal_processor_state_info_t *psp =
+               (pal_processor_state_info_t*)peidx_psp(peidx);
 
-       /* 
-        * We cannot recover errors with other than bus_check.
+       /*
+        * Processor recovery status must key off of the PAL recovery
+        * status in the Processor State Parameter.
         */
-       if (psp->cc || psp->rc || psp->uc) 
-               return 0;
 
        /*
-        * If there is no bus error, record is weird but we need not to recover.
+        * The machine check is corrected.
         */
-       if (psp->bc == 0 || pbci == NULL)
-               return 1;
+       if (psp->cm == 1)
+               return mca_recovered("machine check is already corrected.");
 
        /*
-        * Sorry, we cannot handle so many.
+        * The error was not contained.  Software must be reset.
         */
-       if (peidx_bus_check_num(peidx) > 1)
-               return 0;
+       if (psp->us || psp->ci == 0)
+               return fatal_mca("error not contained");
+
        /*
-        * Well, here is only one bus error.
+        * Look for recoverable TLB check
         */
-       if (pbci->ib || pbci->cc)
-               return 0;
+       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 0;
-       if (psp->ci == 0)
-               return 0;
+               return fatal_mca("External bus check fatal status");
 
        /*
-        * This is a local MCA and estimated as recoverble external bus error.
-        * (e.g. a load from poisoned memory)
-        * This means "there are some platform errors".
+        * This is a local MCA and estimated as a recoverable error.
         */
-       if (platform) 
-               return recover_from_platform_error(slidx, peidx, pbci);
-       /* 
-        * On account of strange SAL error record, we cannot recover. 
+       if (platform)
+               return recover_from_platform_error(slidx, peidx, pbci, sos);
+
+       /*
+        * On account of strange SAL error record, we cannot recover.
         */
-       return 0;
+       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, 
-       ia64_mca_sal_to_os_state_t *sal_to_os_state,
-       ia64_mca_os_to_sal_state_t *os_to_sal_state)
+mca_try_to_recover(void *rec, struct ia64_sal_os_state *sos)
 {
        int platform_err;
        int n_proc_err;
@@ -571,10 +731,6 @@ mca_try_to_recover(void *rec,
        peidx_table_t peidx;
        pal_bus_check_info_t pbci;
 
-       /* handoff state from/to mca.c */
-       sal_to_os_handoff_state = sal_to_os_state;
-       os_to_sal_handoff_state = os_to_sal_state;
-
        /* Make index of SAL error record */
        platform_err = mca_make_slidx(rec, &slidx);
 
@@ -583,25 +739,25 @@ mca_try_to_recover(void *rec,
 
         /* Now, OS can recover when there is one processor error section */
        if (n_proc_err > 1)
-               return 0;
-       else if (n_proc_err == 0) {
-               /* Weird SAL record ... We need not to recover */
-
-               return 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);
+       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))
-               return 0;
+       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);
+       return recover_from_processor_error(platform_err, &slidx, &peidx,
+                                           &pbci, sos);
 }
 
 /*
@@ -614,7 +770,7 @@ int __init mca_external_handler_init(void)
                return -ENOMEM;
 
        /* register external mca handlers */
-       if (ia64_reg_MCA_extension(mca_try_to_recover))       
+       if (ia64_reg_MCA_extension(mca_try_to_recover)) {       
                printk(KERN_ERR "ia64_reg_MCA_extension failed.\n");
                kfree(slidx_pool.buffer);
                return -EFAULT;