Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2110 insertions, 0 deletions

diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c
new file mode 100644
index 000000000..bd0a51dc3
--- /dev/null
+++ b/arch/ia64/kernel/mca.c
@@ -0,0 +1,2110 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * File:	mca.c
+ * Purpose:	Generic MCA handling layer
+ *
+ * Copyright (C) 2003 Hewlett-Packard Co
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * Copyright (C) 2002 Dell Inc.
+ * Copyright (C) Matt Domsch <Matt_Domsch@dell.com>
+ *
+ * Copyright (C) 2002 Intel
+ * Copyright (C) Jenna Hall <jenna.s.hall@intel.com>
+ *
+ * Copyright (C) 2001 Intel
+ * Copyright (C) Fred Lewis <frederick.v.lewis@intel.com>
+ *
+ * Copyright (C) 2000 Intel
+ * Copyright (C) Chuck Fleckenstein <cfleck@co.intel.com>
+ *
+ * Copyright (C) 1999, 2004-2008 Silicon Graphics, Inc.
+ * Copyright (C) Vijay Chander <vijay@engr.sgi.com>
+ *
+ * Copyright (C) 2006 FUJITSU LIMITED
+ * Copyright (C) Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
+ *
+ * 2000-03-29 Chuck Fleckenstein <cfleck@co.intel.com>
+ *	      Fixed PAL/SAL update issues, began MCA bug fixes, logging issues,
+ *	      added min save state dump, added INIT handler.
+ *
+ * 2001-01-03 Fred Lewis <frederick.v.lewis@intel.com>
+ *	      Added setup of CMCI and CPEI IRQs, logging of corrected platform
+ *	      errors, completed code for logging of corrected & uncorrected
+ *	      machine check errors, and updated for conformance with Nov. 2000
+ *	      revision of the SAL 3.0 spec.
+ *
+ * 2002-01-04 Jenna Hall <jenna.s.hall@intel.com>
+ *	      Aligned MCA stack to 16 bytes, added platform vs. CPU error flag,
+ *	      set SAL default return values, changed error record structure to
+ *	      linked list, added init call to sal_get_state_info_size().
+ *
+ * 2002-03-25 Matt Domsch <Matt_Domsch@dell.com>
+ *	      GUID cleanups.
+ *
+ * 2003-04-15 David Mosberger-Tang <davidm@hpl.hp.com>
+ *	      Added INIT backtrace support.
+ *
+ * 2003-12-08 Keith Owens <kaos@sgi.com>
+ *	      smp_call_function() must not be called from interrupt context
+ *	      (can deadlock on tasklist_lock).
+ *	      Use keventd to call smp_call_function().
+ *
+ * 2004-02-01 Keith Owens <kaos@sgi.com>
+ *	      Avoid deadlock when using printk() for MCA and INIT records.
+ *	      Delete all record printing code, moved to salinfo_decode in user
+ *	      space.  Mark variables and functions static where possible.
+ *	      Delete dead variables and functions.  Reorder to remove the need
+ *	      for forward declarations and to consolidate related code.
+ *
+ * 2005-08-12 Keith Owens <kaos@sgi.com>
+ *	      Convert MCA/INIT handlers to use per event stacks and SAL/OS
+ *	      state.
+ *
+ * 2005-10-07 Keith Owens <kaos@sgi.com>
+ *	      Add notify_die() hooks.
+ *
+ * 2006-09-15 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
+ *	      Add printing support for MCA/INIT.
+ *
+ * 2007-04-27 Russ Anderson <rja@sgi.com>
+ *	      Support multiple cpus going through OS_MCA in the same event.
+ */
+#include <linux/jiffies.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/interrupt.h>
+#include <linux/irq.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/cpumask.h>
+#include <linux/kdebug.h>
+#include <linux/cpu.h>
+#include <linux/gfp.h>
+
+#include <asm/delay.h>
+#include <asm/meminit.h>
+#include <asm/page.h>
+#include <asm/ptrace.h>
+#include <asm/sal.h>
+#include <asm/mca.h>
+#include <asm/kexec.h>
+
+#include <asm/irq.h>
+#include <asm/hw_irq.h>
+#include <asm/tlb.h>
+
+#include "mca_drv.h"
+#include "entry.h"
+#include "irq.h"
+
+#if defined(IA64_MCA_DEBUG_INFO)
+# define IA64_MCA_DEBUG(fmt...)	printk(fmt)
+#else
+# define IA64_MCA_DEBUG(fmt...)
+#endif
+
+#define NOTIFY_INIT(event, regs, arg, spin)				\
+do {									\
+	if ((notify_die((event), "INIT", (regs), (arg), 0, 0)		\
+			== NOTIFY_STOP) && ((spin) == 1))		\
+		ia64_mca_spin(__func__);				\
+} while (0)
+
+#define NOTIFY_MCA(event, regs, arg, spin)				\
+do {									\
+	if ((notify_die((event), "MCA", (regs), (arg), 0, 0)		\
+			== NOTIFY_STOP) && ((spin) == 1))		\
+		ia64_mca_spin(__func__);				\
+} while (0)
+
+/* Used by mca_asm.S */
+DEFINE_PER_CPU(u64, ia64_mca_data); /* == __per_cpu_mca[smp_processor_id()] */
+DEFINE_PER_CPU(u64, ia64_mca_per_cpu_pte); /* PTE to map per-CPU area */
+DEFINE_PER_CPU(u64, ia64_mca_pal_pte);	    /* PTE to map PAL code */
+DEFINE_PER_CPU(u64, ia64_mca_pal_base);    /* vaddr PAL code granule */
+DEFINE_PER_CPU(u64, ia64_mca_tr_reload);   /* Flag for TR reload */
+
+unsigned long __per_cpu_mca[NR_CPUS];
+
+/* In mca_asm.S */
+extern void			ia64_os_init_dispatch_monarch (void);
+extern void			ia64_os_init_dispatch_slave (void);
+
+static int monarch_cpu = -1;
+
+static ia64_mc_info_t		ia64_mc_info;
+
+#define MAX_CPE_POLL_INTERVAL (15*60*HZ) /* 15 minutes */
+#define MIN_CPE_POLL_INTERVAL (2*60*HZ)  /* 2 minutes */
+#define CMC_POLL_INTERVAL     (1*60*HZ)  /* 1 minute */
+#define CPE_HISTORY_LENGTH    5
+#define CMC_HISTORY_LENGTH    5
+
+static struct timer_list cpe_poll_timer;
+static struct timer_list cmc_poll_timer;
+/*
+ * This variable tells whether we are currently in polling mode.
+ * Start with this in the wrong state so we won't play w/ timers
+ * before the system is ready.
+ */
+static int cmc_polling_enabled = 1;
+
+/*
+ * Clearing this variable prevents CPE polling from getting activated
+ * in mca_late_init.  Use it if your system doesn't provide a CPEI,
+ * but encounters problems retrieving CPE logs.  This should only be
+ * necessary for debugging.
+ */
+static int cpe_poll_enabled = 1;
+
+extern void salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe);
+
+static int mca_init __initdata;
+
+/*
+ * limited & delayed printing support for MCA/INIT handler
+ */
+
+#define mprintk(fmt...) ia64_mca_printk(fmt)
+
+#define MLOGBUF_SIZE (512+256*NR_CPUS)
+#define MLOGBUF_MSGMAX 256
+static char mlogbuf[MLOGBUF_SIZE];
+static DEFINE_SPINLOCK(mlogbuf_wlock);	/* mca context only */
+static DEFINE_SPINLOCK(mlogbuf_rlock);	/* normal context only */
+static unsigned long mlogbuf_start;
+static unsigned long mlogbuf_end;
+static unsigned int mlogbuf_finished = 0;
+static unsigned long mlogbuf_timestamp = 0;
+
+static int loglevel_save = -1;
+#define BREAK_LOGLEVEL(__console_loglevel)		\
+	oops_in_progress = 1;				\
+	if (loglevel_save < 0)				\
+		loglevel_save = __console_loglevel;	\
+	__console_loglevel = 15;
+
+#define RESTORE_LOGLEVEL(__console_loglevel)		\
+	if (loglevel_save >= 0) {			\
+		__console_loglevel = loglevel_save;	\
+		loglevel_save = -1;			\
+	}						\
+	mlogbuf_finished = 0;				\
+	oops_in_progress = 0;
+
+/*
+ * Push messages into buffer, print them later if not urgent.
+ */
+void ia64_mca_printk(const char *fmt, ...)
+{
+	va_list args;
+	int printed_len;
+	char temp_buf[MLOGBUF_MSGMAX];
+	char *p;
+
+	va_start(args, fmt);
+	printed_len = vscnprintf(temp_buf, sizeof(temp_buf), fmt, args);
+	va_end(args);
+
+	/* Copy the output into mlogbuf */
+	if (oops_in_progress) {
+		/* mlogbuf was abandoned, use printk directly instead. */
+		printk("%s", temp_buf);
+	} else {
+		spin_lock(&mlogbuf_wlock);
+		for (p = temp_buf; *p; p++) {
+			unsigned long next = (mlogbuf_end + 1) % MLOGBUF_SIZE;
+			if (next != mlogbuf_start) {
+				mlogbuf[mlogbuf_end] = *p;
+				mlogbuf_end = next;
+			} else {
+				/* buffer full */
+				break;
+			}
+		}
+		mlogbuf[mlogbuf_end] = '\0';
+		spin_unlock(&mlogbuf_wlock);
+	}
+}
+EXPORT_SYMBOL(ia64_mca_printk);
+
+/*
+ * Print buffered messages.
+ *  NOTE: call this after returning normal context. (ex. from salinfod)
+ */
+void ia64_mlogbuf_dump(void)
+{
+	char temp_buf[MLOGBUF_MSGMAX];
+	char *p;
+	unsigned long index;
+	unsigned long flags;
+	unsigned int printed_len;
+
+	/* Get output from mlogbuf */
+	while (mlogbuf_start != mlogbuf_end) {
+		temp_buf[0] = '\0';
+		p = temp_buf;
+		printed_len = 0;
+
+		spin_lock_irqsave(&mlogbuf_rlock, flags);
+
+		index = mlogbuf_start;
+		while (index != mlogbuf_end) {
+			*p = mlogbuf[index];
+			index = (index + 1) % MLOGBUF_SIZE;
+			if (!*p)
+				break;
+			p++;
+			if (++printed_len >= MLOGBUF_MSGMAX - 1)
+				break;
+		}
+		*p = '\0';
+		if (temp_buf[0])
+			printk("%s", temp_buf);
+		mlogbuf_start = index;
+
+		mlogbuf_timestamp = 0;
+		spin_unlock_irqrestore(&mlogbuf_rlock, flags);
+	}
+}
+EXPORT_SYMBOL(ia64_mlogbuf_dump);
+
+/*
+ * Call this if system is going to down or if immediate flushing messages to
+ * console is required. (ex. recovery was failed, crash dump is going to be
+ * invoked, long-wait rendezvous etc.)
+ *  NOTE: this should be called from monarch.
+ */
+static void ia64_mlogbuf_finish(int wait)
+{
+	BREAK_LOGLEVEL(console_loglevel);
+
+	spin_lock_init(&mlogbuf_rlock);
+	ia64_mlogbuf_dump();
+	printk(KERN_EMERG "mlogbuf_finish: printing switched to urgent mode, "
+		"MCA/INIT might be dodgy or fail.\n");
+
+	if (!wait)
+		return;
+
+	/* wait for console */
+	printk("Delaying for 5 seconds...\n");
+	udelay(5*1000000);
+
+	mlogbuf_finished = 1;
+}
+
+/*
+ * Print buffered messages from INIT context.
+ */
+static void ia64_mlogbuf_dump_from_init(void)
+{
+	if (mlogbuf_finished)
+		return;
+
+	if (mlogbuf_timestamp &&
+			time_before(jiffies, mlogbuf_timestamp + 30 * HZ)) {
+		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT "
+			" and the system seems to be messed up.\n");
+		ia64_mlogbuf_finish(0);
+		return;
+	}
+
+	if (!spin_trylock(&mlogbuf_rlock)) {
+		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT. "
+			"Generated messages other than stack dump will be "
+			"buffered to mlogbuf and will be printed later.\n");
+		printk(KERN_ERR "INIT: If messages would not printed after "
+			"this INIT, wait 30sec and assert INIT again.\n");
+		if (!mlogbuf_timestamp)
+			mlogbuf_timestamp = jiffies;
+		return;
+	}
+	spin_unlock(&mlogbuf_rlock);
+	ia64_mlogbuf_dump();
+}
+
+static inline void
+ia64_mca_spin(const char *func)
+{
+	if (monarch_cpu == smp_processor_id())
+		ia64_mlogbuf_finish(0);
+	mprintk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
+	while (1)
+		cpu_relax();
+}
+/*
+ * IA64_MCA log support
+ */
+#define IA64_MAX_LOGS		2	/* Double-buffering for nested MCAs */
+#define IA64_MAX_LOG_TYPES      4   /* MCA, INIT, CMC, CPE */
+
+typedef struct ia64_state_log_s
+{
+	spinlock_t	isl_lock;
+	int		isl_index;
+	unsigned long	isl_count;
+	ia64_err_rec_t  *isl_log[IA64_MAX_LOGS]; /* need space to store header + error log */
+} ia64_state_log_t;
+
+static ia64_state_log_t ia64_state_log[IA64_MAX_LOG_TYPES];
+
+#define IA64_LOG_LOCK_INIT(it) spin_lock_init(&ia64_state_log[it].isl_lock)
+#define IA64_LOG_LOCK(it)      spin_lock_irqsave(&ia64_state_log[it].isl_lock, s)
+#define IA64_LOG_UNLOCK(it)    spin_unlock_irqrestore(&ia64_state_log[it].isl_lock,s)
+#define IA64_LOG_NEXT_INDEX(it)    ia64_state_log[it].isl_index
+#define IA64_LOG_CURR_INDEX(it)    1 - ia64_state_log[it].isl_index
+#define IA64_LOG_INDEX_INC(it) \
+    {ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index; \
+    ia64_state_log[it].isl_count++;}
+#define IA64_LOG_INDEX_DEC(it) \
+    ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index
+#define IA64_LOG_NEXT_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)]))
+#define IA64_LOG_CURR_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)]))
+#define IA64_LOG_COUNT(it)         ia64_state_log[it].isl_count
+
+static inline void ia64_log_allocate(int it, u64 size)
+{
+	ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)] =
+		(ia64_err_rec_t *)memblock_alloc(size, SMP_CACHE_BYTES);
+	if (!ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)])
+		panic("%s: Failed to allocate %llu bytes\n", __func__, size);
+
+	ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)] =
+		(ia64_err_rec_t *)memblock_alloc(size, SMP_CACHE_BYTES);
+	if (!ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)])
+		panic("%s: Failed to allocate %llu bytes\n", __func__, size);
+}
+
+/*
+ * ia64_log_init
+ *	Reset the OS ia64 log buffer
+ * Inputs   :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
+ * Outputs	:	None
+ */
+static void __init
+ia64_log_init(int sal_info_type)
+{
+	u64	max_size = 0;
+
+	IA64_LOG_NEXT_INDEX(sal_info_type) = 0;
+	IA64_LOG_LOCK_INIT(sal_info_type);
+
+	// SAL will tell us the maximum size of any error record of this type
+	max_size = ia64_sal_get_state_info_size(sal_info_type);
+	if (!max_size)
+		/* alloc_bootmem() doesn't like zero-sized allocations! */
+		return;
+
+	// set up OS data structures to hold error info
+	ia64_log_allocate(sal_info_type, max_size);
+}
+
+/*
+ * ia64_log_get
+ *
+ *	Get the current MCA log from SAL and copy it into the OS log buffer.
+ *
+ *  Inputs  :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
+ *              irq_safe    whether you can use printk at this point
+ *  Outputs :   size        (total record length)
+ *              *buffer     (ptr to error record)
+ *
+ */
+static u64
+ia64_log_get(int sal_info_type, u8 **buffer, int irq_safe)
+{
+	sal_log_record_header_t     *log_buffer;
+	u64                         total_len = 0;
+	unsigned long               s;
+
+	IA64_LOG_LOCK(sal_info_type);
+
+	/* Get the process state information */
+	log_buffer = IA64_LOG_NEXT_BUFFER(sal_info_type);
+
+	total_len = ia64_sal_get_state_info(sal_info_type, (u64 *)log_buffer);
+
+	if (total_len) {
+		IA64_LOG_INDEX_INC(sal_info_type);
+		IA64_LOG_UNLOCK(sal_info_type);
+		if (irq_safe) {
+			IA64_MCA_DEBUG("%s: SAL error record type %d retrieved. Record length = %ld\n",
+				       __func__, sal_info_type, total_len);
+		}
+		*buffer = (u8 *) log_buffer;
+		return total_len;
+	} else {
+		IA64_LOG_UNLOCK(sal_info_type);
+		return 0;
+	}
+}
+
+/*
+ *  ia64_mca_log_sal_error_record
+ *
+ *  This function retrieves a specified error record type from SAL
+ *  and wakes up any processes waiting for error records.
+ *
+ *  Inputs  :   sal_info_type   (Type of error record MCA/CMC/CPE)
+ *              FIXME: remove MCA and irq_safe.
+ */
+static void
+ia64_mca_log_sal_error_record(int sal_info_type)
+{
+	u8 *buffer;
+	sal_log_record_header_t *rh;
+	u64 size;
+	int irq_safe = sal_info_type != SAL_INFO_TYPE_MCA;
+#ifdef IA64_MCA_DEBUG_INFO
+	static const char * const rec_name[] = { "MCA", "INIT", "CMC", "CPE" };
+#endif
+
+	size = ia64_log_get(sal_info_type, &buffer, irq_safe);
+	if (!size)
+		return;
+
+	salinfo_log_wakeup(sal_info_type, buffer, size, irq_safe);
+
+	if (irq_safe)
+		IA64_MCA_DEBUG("CPU %d: SAL log contains %s error record\n",
+			smp_processor_id(),
+			sal_info_type < ARRAY_SIZE(rec_name) ? rec_name[sal_info_type] : "UNKNOWN");
+
+	/* Clear logs from corrected errors in case there's no user-level logger */
+	rh = (sal_log_record_header_t *)buffer;
+	if (rh->severity == sal_log_severity_corrected)
+		ia64_sal_clear_state_info(sal_info_type);
+}
+
+/*
+ * search_mca_table
+ *  See if the MCA surfaced in an instruction range
+ *  that has been tagged as recoverable.
+ *
+ *  Inputs
+ *	first	First address range to check
+ *	last	Last address range to check
+ *	ip	Instruction pointer, address we are looking for
+ *
+ * Return value:
+ *      1 on Success (in the table)/ 0 on Failure (not in the  table)
+ */
+int
+search_mca_table (const struct mca_table_entry *first,
+                const struct mca_table_entry *last,
+                unsigned long ip)
+{
+        const struct mca_table_entry *curr;
+        u64 curr_start, curr_end;
+
+        curr = first;
+        while (curr <= last) {
+                curr_start = (u64) &curr->start_addr + curr->start_addr;
+                curr_end = (u64) &curr->end_addr + curr->end_addr;
+
+                if ((ip >= curr_start) && (ip <= curr_end)) {
+                        return 1;
+                }
+                curr++;
+        }
+        return 0;
+}
+
+/* Given an address, look for it in the mca tables. */
+int mca_recover_range(unsigned long addr)
+{
+	extern struct mca_table_entry __start___mca_table[];
+	extern struct mca_table_entry __stop___mca_table[];
+
+	return search_mca_table(__start___mca_table, __stop___mca_table-1, addr);
+}
+EXPORT_SYMBOL_GPL(mca_recover_range);
+
+int cpe_vector = -1;
+int ia64_cpe_irq = -1;
+
+static irqreturn_t
+ia64_mca_cpe_int_handler (int cpe_irq, void *arg)
+{
+	static unsigned long	cpe_history[CPE_HISTORY_LENGTH];
+	static int		index;
+	static DEFINE_SPINLOCK(cpe_history_lock);
+
+	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
+		       __func__, cpe_irq, smp_processor_id());
+
+	/* SAL spec states this should run w/ interrupts enabled */
+	local_irq_enable();
+
+	spin_lock(&cpe_history_lock);
+	if (!cpe_poll_enabled && cpe_vector >= 0) {
+
+		int i, count = 1; /* we know 1 happened now */
+		unsigned long now = jiffies;
+
+		for (i = 0; i < CPE_HISTORY_LENGTH; i++) {
+			if (now - cpe_history[i] <= HZ)
+				count++;
+		}
+
+		IA64_MCA_DEBUG(KERN_INFO "CPE threshold %d/%d\n", count, CPE_HISTORY_LENGTH);
+		if (count >= CPE_HISTORY_LENGTH) {
+
+			cpe_poll_enabled = 1;
+			spin_unlock(&cpe_history_lock);
+			disable_irq_nosync(local_vector_to_irq(IA64_CPE_VECTOR));
+
+			/*
+			 * Corrected errors will still be corrected, but
+			 * make sure there's a log somewhere that indicates
+			 * something is generating more than we can handle.
+			 */
+			printk(KERN_WARNING "WARNING: Switching to polling CPE handler; error records may be lost\n");
+
+			mod_timer(&cpe_poll_timer, jiffies + MIN_CPE_POLL_INTERVAL);
+
+			/* lock already released, get out now */
+			goto out;
+		} else {
+			cpe_history[index++] = now;
+			if (index == CPE_HISTORY_LENGTH)
+				index = 0;
+		}
+	}
+	spin_unlock(&cpe_history_lock);
+out:
+	/* Get the CPE error record and log it */
+	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE);
+
+	local_irq_disable();
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * ia64_mca_register_cpev
+ *
+ *  Register the corrected platform error vector with SAL.
+ *
+ *  Inputs
+ *      cpev        Corrected Platform Error Vector number
+ *
+ *  Outputs
+ *      None
+ */
+void
+ia64_mca_register_cpev (int cpev)
+{
+	/* Register the CPE interrupt vector with SAL */
+	struct ia64_sal_retval isrv;
+
+	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_CPE_INT, SAL_MC_PARAM_MECHANISM_INT, cpev, 0, 0);
+	if (isrv.status) {
+		printk(KERN_ERR "Failed to register Corrected Platform "
+		       "Error interrupt vector with SAL (status %ld)\n", isrv.status);
+		return;
+	}
+
+	IA64_MCA_DEBUG("%s: corrected platform error "
+		       "vector %#x registered\n", __func__, cpev);
+}
+
+/*
+ * ia64_mca_cmc_vector_setup
+ *
+ *  Setup the corrected machine check vector register in the processor.
+ *  (The interrupt is masked on boot. ia64_mca_late_init unmask this.)
+ *  This function is invoked on a per-processor basis.
+ *
+ * Inputs
+ *      None
+ *
+ * Outputs
+ *	None
+ */
+void
+ia64_mca_cmc_vector_setup (void)
+{
+	cmcv_reg_t	cmcv;
+
+	cmcv.cmcv_regval	= 0;
+	cmcv.cmcv_mask		= 1;        /* Mask/disable interrupt at first */
+	cmcv.cmcv_vector	= IA64_CMC_VECTOR;
+	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
+
+	IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x registered.\n",
+		       __func__, smp_processor_id(), IA64_CMC_VECTOR);
+
+	IA64_MCA_DEBUG("%s: CPU %d CMCV = %#016lx\n",
+		       __func__, smp_processor_id(), ia64_getreg(_IA64_REG_CR_CMCV));
+}
+
+/*
+ * ia64_mca_cmc_vector_disable
+ *
+ *  Mask the corrected machine check vector register in the processor.
+ *  This function is invoked on a per-processor basis.
+ *
+ * Inputs
+ *      dummy(unused)
+ *
+ * Outputs
+ *	None
+ */
+static void
+ia64_mca_cmc_vector_disable (void *dummy)
+{
+	cmcv_reg_t	cmcv;
+
+	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
+
+	cmcv.cmcv_mask = 1; /* Mask/disable interrupt */
+	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
+
+	IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x disabled.\n",
+		       __func__, smp_processor_id(), cmcv.cmcv_vector);
+}
+
+/*
+ * ia64_mca_cmc_vector_enable
+ *
+ *  Unmask the corrected machine check vector register in the processor.
+ *  This function is invoked on a per-processor basis.
+ *
+ * Inputs
+ *      dummy(unused)
+ *
+ * Outputs
+ *	None
+ */
+static void
+ia64_mca_cmc_vector_enable (void *dummy)
+{
+	cmcv_reg_t	cmcv;
+
+	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
+
+	cmcv.cmcv_mask = 0; /* Unmask/enable interrupt */
+	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
+
+	IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x enabled.\n",
+		       __func__, smp_processor_id(), cmcv.cmcv_vector);
+}
+
+/*
+ * ia64_mca_cmc_vector_disable_keventd
+ *
+ * Called via keventd (smp_call_function() is not safe in interrupt context) to
+ * disable the cmc interrupt vector.
+ */
+static void
+ia64_mca_cmc_vector_disable_keventd(struct work_struct *unused)
+{
+	on_each_cpu(ia64_mca_cmc_vector_disable, NULL, 0);
+}
+
+/*
+ * ia64_mca_cmc_vector_enable_keventd
+ *
+ * Called via keventd (smp_call_function() is not safe in interrupt context) to
+ * enable the cmc interrupt vector.
+ */
+static void
+ia64_mca_cmc_vector_enable_keventd(struct work_struct *unused)
+{
+	on_each_cpu(ia64_mca_cmc_vector_enable, NULL, 0);
+}
+
+/*
+ * ia64_mca_wakeup
+ *
+ *	Send an inter-cpu interrupt to wake-up a particular cpu.
+ *
+ *  Inputs  :   cpuid
+ *  Outputs :   None
+ */
+static void
+ia64_mca_wakeup(int cpu)
+{
+	ia64_send_ipi(cpu, IA64_MCA_WAKEUP_VECTOR, IA64_IPI_DM_INT, 0);
+}
+
+/*
+ * ia64_mca_wakeup_all
+ *
+ *	Wakeup all the slave cpus which have rendez'ed previously.
+ *
+ *  Inputs  :   None
+ *  Outputs :   None
+ */
+static void
+ia64_mca_wakeup_all(void)
+{
+	int cpu;
+
+	/* Clear the Rendez checkin flag for all cpus */
+	for_each_online_cpu(cpu) {
+		if (ia64_mc_info.imi_rendez_checkin[cpu] == IA64_MCA_RENDEZ_CHECKIN_DONE)
+			ia64_mca_wakeup(cpu);
+	}
+
+}
+
+/*
+ * ia64_mca_rendez_interrupt_handler
+ *
+ *	This is handler used to put slave processors into spinloop
+ *	while the monarch processor does the mca handling and later
+ *	wake each slave up once the monarch is done.  The state
+ *	IA64_MCA_RENDEZ_CHECKIN_DONE indicates the cpu is rendez'ed
+ *	in SAL.  The state IA64_MCA_RENDEZ_CHECKIN_NOTDONE indicates
+ *	the cpu has come out of OS rendezvous.
+ *
+ *  Inputs  :   None
+ *  Outputs :   None
+ */
+static irqreturn_t
+ia64_mca_rendez_int_handler(int rendez_irq, void *arg)
+{
+	unsigned long flags;
+	int cpu = smp_processor_id();
+	struct ia64_mca_notify_die nd =
+		{ .sos = NULL, .monarch_cpu = &monarch_cpu };
+
+	/* Mask all interrupts */
+	local_irq_save(flags);
+
+	NOTIFY_MCA(DIE_MCA_RENDZVOUS_ENTER, get_irq_regs(), (long)&nd, 1);
+
+	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_DONE;
+	/* Register with the SAL monarch that the slave has
+	 * reached SAL
+	 */
+	ia64_sal_mc_rendez();
+
+	NOTIFY_MCA(DIE_MCA_RENDZVOUS_PROCESS, get_irq_regs(), (long)&nd, 1);
+
+	/* Wait for the monarch cpu to exit. */
+	while (monarch_cpu != -1)
+	       cpu_relax();	/* spin until monarch leaves */
+
+	NOTIFY_MCA(DIE_MCA_RENDZVOUS_LEAVE, get_irq_regs(), (long)&nd, 1);
+
+	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
+	/* Enable all interrupts */
+	local_irq_restore(flags);
+	return IRQ_HANDLED;
+}
+
+/*
+ * ia64_mca_wakeup_int_handler
+ *
+ *	The interrupt handler for processing the inter-cpu interrupt to the
+ *	slave cpu which was spinning in the rendez loop.
+ *	Since this spinning is done by turning off the interrupts and
+ *	polling on the wakeup-interrupt bit in the IRR, there is
+ *	nothing useful to be done in the handler.
+ *
+ *  Inputs  :   wakeup_irq  (Wakeup-interrupt bit)
+ *	arg		(Interrupt handler specific argument)
+ *  Outputs :   None
+ *
+ */
+static irqreturn_t
+ia64_mca_wakeup_int_handler(int wakeup_irq, void *arg)
+{
+	return IRQ_HANDLED;
+}
+
+/* Function pointer for extra MCA recovery */
+int (*ia64_mca_ucmc_extension)
+	(void*,struct ia64_sal_os_state*)
+	= NULL;
+
+int
+ia64_reg_MCA_extension(int (*fn)(void *, struct ia64_sal_os_state *))
+{
+	if (ia64_mca_ucmc_extension)
+		return 1;
+
+	ia64_mca_ucmc_extension = fn;
+	return 0;
+}
+
+void
+ia64_unreg_MCA_extension(void)
+{
+	if (ia64_mca_ucmc_extension)
+		ia64_mca_ucmc_extension = NULL;
+}
+
+EXPORT_SYMBOL(ia64_reg_MCA_extension);
+EXPORT_SYMBOL(ia64_unreg_MCA_extension);
+
+
+static inline void
+copy_reg(const u64 *fr, u64 fnat, unsigned long *tr, unsigned long *tnat)
+{
+	u64 fslot, tslot, nat;
+	*tr = *fr;
+	fslot = ((unsigned long)fr >> 3) & 63;
+	tslot = ((unsigned long)tr >> 3) & 63;
+	*tnat &= ~(1UL << tslot);
+	nat = (fnat >> fslot) & 1;
+	*tnat |= (nat << tslot);
+}
+
+/* Change the comm field on the MCA/INT task to include the pid that
+ * was interrupted, it makes for easier debugging.  If that pid was 0
+ * (swapper or nested MCA/INIT) then use the start of the previous comm
+ * field suffixed with its cpu.
+ */
+
+static void
+ia64_mca_modify_comm(const struct task_struct *previous_current)
+{
+	char *p, comm[sizeof(current->comm)];
+	if (previous_current->pid)
+		snprintf(comm, sizeof(comm), "%s %d",
+			current->comm, previous_current->pid);
+	else {
+		int l;
+		if ((p = strchr(previous_current->comm, ' ')))
+			l = p - previous_current->comm;
+		else
+			l = strlen(previous_current->comm);
+		snprintf(comm, sizeof(comm), "%s %*s %d",
+			current->comm, l, previous_current->comm,
+			task_thread_info(previous_current)->cpu);
+	}
+	memcpy(current->comm, comm, sizeof(current->comm));
+}
+
+static void
+finish_pt_regs(struct pt_regs *regs, struct ia64_sal_os_state *sos,
+		unsigned long *nat)
+{
+	const pal_min_state_area_t *ms = sos->pal_min_state;
+	const u64 *bank;
+
+	/* If ipsr.ic then use pmsa_{iip,ipsr,ifs}, else use
+	 * pmsa_{xip,xpsr,xfs}
+	 */
+	if (ia64_psr(regs)->ic) {
+		regs->cr_iip = ms->pmsa_iip;
+		regs->cr_ipsr = ms->pmsa_ipsr;
+		regs->cr_ifs = ms->pmsa_ifs;
+	} else {
+		regs->cr_iip = ms->pmsa_xip;
+		regs->cr_ipsr = ms->pmsa_xpsr;
+		regs->cr_ifs = ms->pmsa_xfs;
+
+		sos->iip = ms->pmsa_iip;
+		sos->ipsr = ms->pmsa_ipsr;
+		sos->ifs = ms->pmsa_ifs;
+	}
+	regs->pr = ms->pmsa_pr;
+	regs->b0 = ms->pmsa_br0;
+	regs->ar_rsc = ms->pmsa_rsc;
+	copy_reg(&ms->pmsa_gr[1-1], ms->pmsa_nat_bits, &regs->r1, nat);
+	copy_reg(&ms->pmsa_gr[2-1], ms->pmsa_nat_bits, &regs->r2, nat);
+	copy_reg(&ms->pmsa_gr[3-1], ms->pmsa_nat_bits, &regs->r3, nat);
+	copy_reg(&ms->pmsa_gr[8-1], ms->pmsa_nat_bits, &regs->r8, nat);
+	copy_reg(&ms->pmsa_gr[9-1], ms->pmsa_nat_bits, &regs->r9, nat);
+	copy_reg(&ms->pmsa_gr[10-1], ms->pmsa_nat_bits, &regs->r10, nat);
+	copy_reg(&ms->pmsa_gr[11-1], ms->pmsa_nat_bits, &regs->r11, nat);
+	copy_reg(&ms->pmsa_gr[12-1], ms->pmsa_nat_bits, &regs->r12, nat);
+	copy_reg(&ms->pmsa_gr[13-1], ms->pmsa_nat_bits, &regs->r13, nat);
+	copy_reg(&ms->pmsa_gr[14-1], ms->pmsa_nat_bits, &regs->r14, nat);
+	copy_reg(&ms->pmsa_gr[15-1], ms->pmsa_nat_bits, &regs->r15, nat);
+	if (ia64_psr(regs)->bn)
+		bank = ms->pmsa_bank1_gr;
+	else
+		bank = ms->pmsa_bank0_gr;
+	copy_reg(&bank[16-16], ms->pmsa_nat_bits, &regs->r16, nat);
+	copy_reg(&bank[17-16], ms->pmsa_nat_bits, &regs->r17, nat);
+	copy_reg(&bank[18-16], ms->pmsa_nat_bits, &regs->r18, nat);
+	copy_reg(&bank[19-16], ms->pmsa_nat_bits, &regs->r19, nat);
+	copy_reg(&bank[20-16], ms->pmsa_nat_bits, &regs->r20, nat);
+	copy_reg(&bank[21-16], ms->pmsa_nat_bits, &regs->r21, nat);
+	copy_reg(&bank[22-16], ms->pmsa_nat_bits, &regs->r22, nat);
+	copy_reg(&bank[23-16], ms->pmsa_nat_bits, &regs->r23, nat);
+	copy_reg(&bank[24-16], ms->pmsa_nat_bits, &regs->r24, nat);
+	copy_reg(&bank[25-16], ms->pmsa_nat_bits, &regs->r25, nat);
+	copy_reg(&bank[26-16], ms->pmsa_nat_bits, &regs->r26, nat);
+	copy_reg(&bank[27-16], ms->pmsa_nat_bits, &regs->r27, nat);
+	copy_reg(&bank[28-16], ms->pmsa_nat_bits, &regs->r28, nat);
+	copy_reg(&bank[29-16], ms->pmsa_nat_bits, &regs->r29, nat);
+	copy_reg(&bank[30-16], ms->pmsa_nat_bits, &regs->r30, nat);
+	copy_reg(&bank[31-16], ms->pmsa_nat_bits, &regs->r31, nat);
+}
+
+/* On entry to this routine, we are running on the per cpu stack, see
+ * mca_asm.h.  The original stack has not been touched by this event.  Some of
+ * the original stack's registers will be in the RBS on this stack.  This stack
+ * also contains a partial pt_regs and switch_stack, the rest of the data is in
+ * PAL minstate.
+ *
+ * The first thing to do is modify the original stack to look like a blocked
+ * task so we can run backtrace on the original task.  Also mark the per cpu
+ * stack as current to ensure that we use the correct task state, it also means
+ * that we can do backtrace on the MCA/INIT handler code itself.
+ */
+
+static struct task_struct *
+ia64_mca_modify_original_stack(struct pt_regs *regs,
+		const struct switch_stack *sw,
+		struct ia64_sal_os_state *sos,
+		const char *type)
+{
+	char *p;
+	ia64_va va;
+	extern char ia64_leave_kernel[];	/* Need asm address, not function descriptor */
+	const pal_min_state_area_t *ms = sos->pal_min_state;
+	struct task_struct *previous_current;
+	struct pt_regs *old_regs;
+	struct switch_stack *old_sw;
+	unsigned size = sizeof(struct pt_regs) +
+			sizeof(struct switch_stack) + 16;
+	unsigned long *old_bspstore, *old_bsp;
+	unsigned long *new_bspstore, *new_bsp;
+	unsigned long old_unat, old_rnat, new_rnat, nat;
+	u64 slots, loadrs = regs->loadrs;
+	u64 r12 = ms->pmsa_gr[12-1], r13 = ms->pmsa_gr[13-1];
+	u64 ar_bspstore = regs->ar_bspstore;
+	u64 ar_bsp = regs->ar_bspstore + (loadrs >> 16);
+	const char *msg;
+	int cpu = smp_processor_id();
+
+	previous_current = curr_task(cpu);
+	ia64_set_curr_task(cpu, current);
+	if ((p = strchr(current->comm, ' ')))
+		*p = '\0';
+
+	/* Best effort attempt to cope with MCA/INIT delivered while in
+	 * physical mode.
+	 */
+	regs->cr_ipsr = ms->pmsa_ipsr;
+	if (ia64_psr(regs)->dt == 0) {
+		va.l = r12;
+		if (va.f.reg == 0) {
+			va.f.reg = 7;
+			r12 = va.l;
+		}
+		va.l = r13;
+		if (va.f.reg == 0) {
+			va.f.reg = 7;
+			r13 = va.l;
+		}
+	}
+	if (ia64_psr(regs)->rt == 0) {
+		va.l = ar_bspstore;
+		if (va.f.reg == 0) {
+			va.f.reg = 7;
+			ar_bspstore = va.l;
+		}
+		va.l = ar_bsp;
+		if (va.f.reg == 0) {
+			va.f.reg = 7;
+			ar_bsp = va.l;
+		}
+	}
+
+	/* mca_asm.S ia64_old_stack() cannot assume that the dirty registers
+	 * have been copied to the old stack, the old stack may fail the
+	 * validation tests below.  So ia64_old_stack() must restore the dirty
+	 * registers from the new stack.  The old and new bspstore probably
+	 * have different alignments, so loadrs calculated on the old bsp
+	 * cannot be used to restore from the new bsp.  Calculate a suitable
+	 * loadrs for the new stack and save it in the new pt_regs, where
+	 * ia64_old_stack() can get it.
+	 */
+	old_bspstore = (unsigned long *)ar_bspstore;
+	old_bsp = (unsigned long *)ar_bsp;
+	slots = ia64_rse_num_regs(old_bspstore, old_bsp);
+	new_bspstore = (unsigned long *)((u64)current + IA64_RBS_OFFSET);
+	new_bsp = ia64_rse_skip_regs(new_bspstore, slots);
+	regs->loadrs = (new_bsp - new_bspstore) * 8 << 16;
+
+	/* Verify the previous stack state before we change it */
+	if (user_mode(regs)) {
+		msg = "occurred in user space";
+		/* previous_current is guaranteed to be valid when the task was
+		 * in user space, so ...
+		 */
+		ia64_mca_modify_comm(previous_current);
+		goto no_mod;
+	}
+
+	if (r13 != sos->prev_IA64_KR_CURRENT) {
+		msg = "inconsistent previous current and r13";
+		goto no_mod;
+	}
+
+	if (!mca_recover_range(ms->pmsa_iip)) {
+		if ((r12 - r13) >= KERNEL_STACK_SIZE) {
+			msg = "inconsistent r12 and r13";
+			goto no_mod;
+		}
+		if ((ar_bspstore - r13) >= KERNEL_STACK_SIZE) {
+			msg = "inconsistent ar.bspstore and r13";
+			goto no_mod;
+		}
+		va.p = old_bspstore;
+		if (va.f.reg < 5) {
+			msg = "old_bspstore is in the wrong region";
+			goto no_mod;
+		}
+		if ((ar_bsp - r13) >= KERNEL_STACK_SIZE) {
+			msg = "inconsistent ar.bsp and r13";
+			goto no_mod;
+		}
+		size += (ia64_rse_skip_regs(old_bspstore, slots) - old_bspstore) * 8;
+		if (ar_bspstore + size > r12) {
+			msg = "no room for blocked state";
+			goto no_mod;
+		}
+	}
+
+	ia64_mca_modify_comm(previous_current);
+
+	/* Make the original task look blocked.  First stack a struct pt_regs,
+	 * describing the state at the time of interrupt.  mca_asm.S built a
+	 * partial pt_regs, copy it and fill in the blanks using minstate.
+	 */
+	p = (char *)r12 - sizeof(*regs);
+	old_regs = (struct pt_regs *)p;
+	memcpy(old_regs, regs, sizeof(*regs));
+	old_regs->loadrs = loadrs;
+	old_unat = old_regs->ar_unat;
+	finish_pt_regs(old_regs, sos, &old_unat);
+
+	/* Next stack a struct switch_stack.  mca_asm.S built a partial
+	 * switch_stack, copy it and fill in the blanks using pt_regs and
+	 * minstate.
+	 *
+	 * In the synthesized switch_stack, b0 points to ia64_leave_kernel,
+	 * ar.pfs is set to 0.
+	 *
+	 * unwind.c::unw_unwind() does special processing for interrupt frames.
+	 * It checks if the PRED_NON_SYSCALL predicate is set, if the predicate
+	 * is clear then unw_unwind() does _not_ adjust bsp over pt_regs.  Not
+	 * that this is documented, of course.  Set PRED_NON_SYSCALL in the
+	 * switch_stack on the original stack so it will unwind correctly when
+	 * unwind.c reads pt_regs.
+	 *
+	 * thread.ksp is updated to point to the synthesized switch_stack.
+	 */
+	p -= sizeof(struct switch_stack);
+	old_sw = (struct switch_stack *)p;
+	memcpy(old_sw, sw, sizeof(*sw));
+	old_sw->caller_unat = old_unat;
+	old_sw->ar_fpsr = old_regs->ar_fpsr;
+	copy_reg(&ms->pmsa_gr[4-1], ms->pmsa_nat_bits, &old_sw->r4, &old_unat);
+	copy_reg(&ms->pmsa_gr[5-1], ms->pmsa_nat_bits, &old_sw->r5, &old_unat);
+	copy_reg(&ms->pmsa_gr[6-1], ms->pmsa_nat_bits, &old_sw->r6, &old_unat);
+	copy_reg(&ms->pmsa_gr[7-1], ms->pmsa_nat_bits, &old_sw->r7, &old_unat);
+	old_sw->b0 = (u64)ia64_leave_kernel;
+	old_sw->b1 = ms->pmsa_br1;
+	old_sw->ar_pfs = 0;
+	old_sw->ar_unat = old_unat;
+	old_sw->pr = old_regs->pr | (1UL << PRED_NON_SYSCALL);
+	previous_current->thread.ksp = (u64)p - 16;
+
+	/* Finally copy the original stack's registers back to its RBS.
+	 * Registers from ar.bspstore through ar.bsp at the time of the event
+	 * are in the current RBS, copy them back to the original stack.  The
+	 * copy must be done register by register because the original bspstore
+	 * and the current one have different alignments, so the saved RNAT
+	 * data occurs at different places.
+	 *
+	 * mca_asm does cover, so the old_bsp already includes all registers at
+	 * the time of MCA/INIT.  It also does flushrs, so all registers before
+	 * this function have been written to backing store on the MCA/INIT
+	 * stack.
+	 */
+	new_rnat = ia64_get_rnat(ia64_rse_rnat_addr(new_bspstore));
+	old_rnat = regs->ar_rnat;
+	while (slots--) {
+		if (ia64_rse_is_rnat_slot(new_bspstore)) {
+			new_rnat = ia64_get_rnat(new_bspstore++);
+		}
+		if (ia64_rse_is_rnat_slot(old_bspstore)) {
+			*old_bspstore++ = old_rnat;
+			old_rnat = 0;
+		}
+		nat = (new_rnat >> ia64_rse_slot_num(new_bspstore)) & 1UL;
+		old_rnat &= ~(1UL << ia64_rse_slot_num(old_bspstore));
+		old_rnat |= (nat << ia64_rse_slot_num(old_bspstore));
+		*old_bspstore++ = *new_bspstore++;
+	}
+	old_sw->ar_bspstore = (unsigned long)old_bspstore;
+	old_sw->ar_rnat = old_rnat;
+
+	sos->prev_task = previous_current;
+	return previous_current;
+
+no_mod:
+	mprintk(KERN_INFO "cpu %d, %s %s, original stack not modified\n",
+			smp_processor_id(), type, msg);
+	old_unat = regs->ar_unat;
+	finish_pt_regs(regs, sos, &old_unat);
+	return previous_current;
+}
+
+/* The monarch/slave interaction is based on monarch_cpu and requires that all
+ * slaves have entered rendezvous before the monarch leaves.  If any cpu has
+ * not entered rendezvous yet then wait a bit.  The assumption is that any
+ * slave that has not rendezvoused after a reasonable time is never going to do
+ * so.  In this context, slave includes cpus that respond to the MCA rendezvous
+ * interrupt, as well as cpus that receive the INIT slave event.
+ */
+
+static void
+ia64_wait_for_slaves(int monarch, const char *type)
+{
+	int c, i , wait;
+
+	/*
+	 * wait 5 seconds total for slaves (arbitrary)
+	 */
+	for (i = 0; i < 5000; i++) {
+		wait = 0;
+		for_each_online_cpu(c) {
+			if (c == monarch)
+				continue;
+			if (ia64_mc_info.imi_rendez_checkin[c]
+					== IA64_MCA_RENDEZ_CHECKIN_NOTDONE) {
+				udelay(1000);		/* short wait */
+				wait = 1;
+				break;
+			}
+		}
+		if (!wait)
+			goto all_in;
+	}
+
+	/*
+	 * Maybe slave(s) dead. Print buffered messages immediately.
+	 */
+	ia64_mlogbuf_finish(0);
+	mprintk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
+	for_each_online_cpu(c) {
+		if (c == monarch)
+			continue;
+		if (ia64_mc_info.imi_rendez_checkin[c] == IA64_MCA_RENDEZ_CHECKIN_NOTDONE)
+			mprintk(" %d", c);
+	}
+	mprintk("\n");
+	return;
+
+all_in:
+	mprintk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
+	return;
+}
+
+/*  mca_insert_tr
+ *
+ *  Switch rid when TR reload and needed!
+ *  iord: 1: itr, 2: itr;
+ *
+*/
+static void mca_insert_tr(u64 iord)
+{
+
+	int i;
+	u64 old_rr;
+	struct ia64_tr_entry *p;
+	unsigned long psr;
+	int cpu = smp_processor_id();
+
+	if (!ia64_idtrs[cpu])
+		return;
+
+	psr = ia64_clear_ic();
+	for (i = IA64_TR_ALLOC_BASE; i < IA64_TR_ALLOC_MAX; i++) {
+		p = ia64_idtrs[cpu] + (iord - 1) * IA64_TR_ALLOC_MAX;
+		if (p->pte & 0x1) {
+			old_rr = ia64_get_rr(p->ifa);
+			if (old_rr != p->rr) {
+				ia64_set_rr(p->ifa, p->rr);
+				ia64_srlz_d();
+			}
+			ia64_ptr(iord, p->ifa, p->itir >> 2);
+			ia64_srlz_i();
+			if (iord & 0x1) {
+				ia64_itr(0x1, i, p->ifa, p->pte, p->itir >> 2);
+				ia64_srlz_i();
+			}
+			if (iord & 0x2) {
+				ia64_itr(0x2, i, p->ifa, p->pte, p->itir >> 2);
+				ia64_srlz_i();
+			}
+			if (old_rr != p->rr) {
+				ia64_set_rr(p->ifa, old_rr);
+				ia64_srlz_d();
+			}
+		}
+	}
+	ia64_set_psr(psr);
+}
+
+/*
+ * ia64_mca_handler
+ *
+ *	This is uncorrectable machine check handler called from OS_MCA
+ *	dispatch code which is in turn called from SAL_CHECK().
+ *	This is the place where the core of OS MCA handling is done.
+ *	Right now the logs are extracted and displayed in a well-defined
+ *	format. This handler code is supposed to be run only on the
+ *	monarch processor. Once the monarch is done with MCA handling
+ *	further MCA logging is enabled by clearing logs.
+ *	Monarch also has the duty of sending wakeup-IPIs to pull the
+ *	slave processors out of rendezvous spinloop.
+ *
+ *	If multiple processors call into OS_MCA, the first will become
+ *	the monarch.  Subsequent cpus will be recorded in the mca_cpu
+ *	bitmask.  After the first monarch has processed its MCA, it
+ *	will wake up the next cpu in the mca_cpu bitmask and then go
+ *	into the rendezvous loop.  When all processors have serviced
+ *	their MCA, the last monarch frees up the rest of the processors.
+ */
+void
+ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
+		 struct ia64_sal_os_state *sos)
+{
+	int recover, cpu = smp_processor_id();
+	struct task_struct *previous_current;
+	struct ia64_mca_notify_die nd =
+		{ .sos = sos, .monarch_cpu = &monarch_cpu, .data = &recover };
+	static atomic_t mca_count;
+	static cpumask_t mca_cpu;
+
+	if (atomic_add_return(1, &mca_count) == 1) {
+		monarch_cpu = cpu;
+		sos->monarch = 1;
+	} else {
+		cpumask_set_cpu(cpu, &mca_cpu);
+		sos->monarch = 0;
+	}
+	mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d "
+		"monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch);
+
+	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA");
+
+	NOTIFY_MCA(DIE_MCA_MONARCH_ENTER, regs, (long)&nd, 1);
+
+	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA;
+	if (sos->monarch) {
+		ia64_wait_for_slaves(cpu, "MCA");
+
+		/* Wakeup all the processors which are spinning in the
+		 * rendezvous loop.  They will leave SAL, then spin in the OS
+		 * with interrupts disabled until this monarch cpu leaves the
+		 * MCA handler.  That gets control back to the OS so we can
+		 * backtrace the other cpus, backtrace when spinning in SAL
+		 * does not work.
+		 */
+		ia64_mca_wakeup_all();
+	} else {
+		while (cpumask_test_cpu(cpu, &mca_cpu))
+			cpu_relax();	/* spin until monarch wakes us */
+	}
+
+	NOTIFY_MCA(DIE_MCA_MONARCH_PROCESS, regs, (long)&nd, 1);
+
+	/* Get the MCA error record and log it */
+	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_MCA);
+
+	/* MCA error recovery */
+	recover = (ia64_mca_ucmc_extension
+		&& ia64_mca_ucmc_extension(
+			IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA),
+			sos));
+
+	if (recover) {
+		sal_log_record_header_t *rh = IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA);
+		rh->severity = sal_log_severity_corrected;
+		ia64_sal_clear_state_info(SAL_INFO_TYPE_MCA);
+		sos->os_status = IA64_MCA_CORRECTED;
+	} else {
+		/* Dump buffered message to console */
+		ia64_mlogbuf_finish(1);
+	}
+
+	if (__this_cpu_read(ia64_mca_tr_reload)) {
+		mca_insert_tr(0x1); /*Reload dynamic itrs*/
+		mca_insert_tr(0x2); /*Reload dynamic itrs*/
+	}
+
+	NOTIFY_MCA(DIE_MCA_MONARCH_LEAVE, regs, (long)&nd, 1);
+
+	if (atomic_dec_return(&mca_count) > 0) {
+		int i;
+
+		/* wake up the next monarch cpu,
+		 * and put this cpu in the rendez loop.
+		 */
+		for_each_online_cpu(i) {
+			if (cpumask_test_cpu(i, &mca_cpu)) {
+				monarch_cpu = i;
+				cpumask_clear_cpu(i, &mca_cpu);	/* wake next cpu */
+				while (monarch_cpu != -1)
+					cpu_relax();	/* spin until last cpu leaves */
+				ia64_set_curr_task(cpu, previous_current);
+				ia64_mc_info.imi_rendez_checkin[cpu]
+						= IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
+				return;
+			}
+		}
+	}
+	ia64_set_curr_task(cpu, previous_current);
+	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
+	monarch_cpu = -1;	/* This frees the slaves and previous monarchs */
+}
+
+static DECLARE_WORK(cmc_disable_work, ia64_mca_cmc_vector_disable_keventd);
+static DECLARE_WORK(cmc_enable_work, ia64_mca_cmc_vector_enable_keventd);
+
+/*
+ * ia64_mca_cmc_int_handler
+ *
+ *  This is corrected machine check interrupt handler.
+ *	Right now the logs are extracted and displayed in a well-defined
+ *	format.
+ *
+ * Inputs
+ *      interrupt number
+ *      client data arg ptr
+ *
+ * Outputs
+ *	None
+ */
+static irqreturn_t
+ia64_mca_cmc_int_handler(int cmc_irq, void *arg)
+{
+	static unsigned long	cmc_history[CMC_HISTORY_LENGTH];
+	static int		index;
+	static DEFINE_SPINLOCK(cmc_history_lock);
+
+	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
+		       __func__, cmc_irq, smp_processor_id());
+
+	/* SAL spec states this should run w/ interrupts enabled */
+	local_irq_enable();
+
+	spin_lock(&cmc_history_lock);
+	if (!cmc_polling_enabled) {
+		int i, count = 1; /* we know 1 happened now */
+		unsigned long now = jiffies;
+
+		for (i = 0; i < CMC_HISTORY_LENGTH; i++) {
+			if (now - cmc_history[i] <= HZ)
+				count++;
+		}
+
+		IA64_MCA_DEBUG(KERN_INFO "CMC threshold %d/%d\n", count, CMC_HISTORY_LENGTH);
+		if (count >= CMC_HISTORY_LENGTH) {
+
+			cmc_polling_enabled = 1;
+			spin_unlock(&cmc_history_lock);
+			/* If we're being hit with CMC interrupts, we won't
+			 * ever execute the schedule_work() below.  Need to
+			 * disable CMC interrupts on this processor now.
+			 */
+			ia64_mca_cmc_vector_disable(NULL);
+			schedule_work(&cmc_disable_work);
+
+			/*
+			 * Corrected errors will still be corrected, but
+			 * make sure there's a log somewhere that indicates
+			 * something is generating more than we can handle.
+			 */
+			printk(KERN_WARNING "WARNING: Switching to polling CMC handler; error records may be lost\n");
+
+			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
+
+			/* lock already released, get out now */
+			goto out;
+		} else {
+			cmc_history[index++] = now;
+			if (index == CMC_HISTORY_LENGTH)
+				index = 0;
+		}
+	}
+	spin_unlock(&cmc_history_lock);
+out:
+	/* Get the CMC error record and log it */
+	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC);
+
+	local_irq_disable();
+
+	return IRQ_HANDLED;
+}
+
+/*
+ *  ia64_mca_cmc_int_caller
+ *
+ * 	Triggered by sw interrupt from CMC polling routine.  Calls
+ * 	real interrupt handler and either triggers a sw interrupt
+ * 	on the next cpu or does cleanup at the end.
+ *
+ * Inputs
+ *	interrupt number
+ *	client data arg ptr
+ * Outputs
+ * 	handled
+ */
+static irqreturn_t
+ia64_mca_cmc_int_caller(int cmc_irq, void *arg)
+{
+	static int start_count = -1;
+	unsigned int cpuid;
+
+	cpuid = smp_processor_id();
+
+	/* If first cpu, update count */
+	if (start_count == -1)
+		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CMC);
+
+	ia64_mca_cmc_int_handler(cmc_irq, arg);
+
+	cpuid = cpumask_next(cpuid+1, cpu_online_mask);
+
+	if (cpuid < nr_cpu_ids) {
+		ia64_send_ipi(cpuid, IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
+	} else {
+		/* If no log record, switch out of polling mode */
+		if (start_count == IA64_LOG_COUNT(SAL_INFO_TYPE_CMC)) {
+
+			printk(KERN_WARNING "Returning to interrupt driven CMC handler\n");
+			schedule_work(&cmc_enable_work);
+			cmc_polling_enabled = 0;
+
+		} else {
+
+			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
+		}
+
+		start_count = -1;
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ *  ia64_mca_cmc_poll
+ *
+ *	Poll for Corrected Machine Checks (CMCs)
+ *
+ * Inputs   :   dummy(unused)
+ * Outputs  :   None
+ *
+ */
+static void
+ia64_mca_cmc_poll (struct timer_list *unused)
+{
+	/* Trigger a CMC interrupt cascade  */
+	ia64_send_ipi(cpumask_first(cpu_online_mask), IA64_CMCP_VECTOR,
+							IA64_IPI_DM_INT, 0);
+}
+
+/*
+ *  ia64_mca_cpe_int_caller
+ *
+ * 	Triggered by sw interrupt from CPE polling routine.  Calls
+ * 	real interrupt handler and either triggers a sw interrupt
+ * 	on the next cpu or does cleanup at the end.
+ *
+ * Inputs
+ *	interrupt number
+ *	client data arg ptr
+ * Outputs
+ * 	handled
+ */
+static irqreturn_t
+ia64_mca_cpe_int_caller(int cpe_irq, void *arg)
+{
+	static int start_count = -1;
+	static int poll_time = MIN_CPE_POLL_INTERVAL;
+	unsigned int cpuid;
+
+	cpuid = smp_processor_id();
+
+	/* If first cpu, update count */
+	if (start_count == -1)
+		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CPE);
+
+	ia64_mca_cpe_int_handler(cpe_irq, arg);
+
+	cpuid = cpumask_next(cpuid+1, cpu_online_mask);
+
+	if (cpuid < NR_CPUS) {
+		ia64_send_ipi(cpuid, IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
+	} else {
+		/*
+		 * If a log was recorded, increase our polling frequency,
+		 * otherwise, backoff or return to interrupt mode.
+		 */
+		if (start_count != IA64_LOG_COUNT(SAL_INFO_TYPE_CPE)) {
+			poll_time = max(MIN_CPE_POLL_INTERVAL, poll_time / 2);
+		} else if (cpe_vector < 0) {
+			poll_time = min(MAX_CPE_POLL_INTERVAL, poll_time * 2);
+		} else {
+			poll_time = MIN_CPE_POLL_INTERVAL;
+
+			printk(KERN_WARNING "Returning to interrupt driven CPE handler\n");
+			enable_irq(local_vector_to_irq(IA64_CPE_VECTOR));
+			cpe_poll_enabled = 0;
+		}
+
+		if (cpe_poll_enabled)
+			mod_timer(&cpe_poll_timer, jiffies + poll_time);
+		start_count = -1;
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ *  ia64_mca_cpe_poll
+ *
+ *	Poll for Corrected Platform Errors (CPEs), trigger interrupt
+ *	on first cpu, from there it will trickle through all the cpus.
+ *
+ * Inputs   :   dummy(unused)
+ * Outputs  :   None
+ *
+ */
+static void
+ia64_mca_cpe_poll (struct timer_list *unused)
+{
+	/* Trigger a CPE interrupt cascade  */
+	ia64_send_ipi(cpumask_first(cpu_online_mask), IA64_CPEP_VECTOR,
+							IA64_IPI_DM_INT, 0);
+}
+
+static int
+default_monarch_init_process(struct notifier_block *self, unsigned long val, void *data)
+{
+	int c;
+	struct task_struct *g, *t;
+	if (val != DIE_INIT_MONARCH_PROCESS)
+		return NOTIFY_DONE;
+#ifdef CONFIG_KEXEC
+	if (atomic_read(&kdump_in_progress))
+		return NOTIFY_DONE;
+#endif
+
+	/*
+	 * FIXME: mlogbuf will brim over with INIT stack dumps.
+	 * To enable show_stack from INIT, we use oops_in_progress which should
+	 * be used in real oops. This would cause something wrong after INIT.
+	 */
+	BREAK_LOGLEVEL(console_loglevel);
+	ia64_mlogbuf_dump_from_init();
+
+	printk(KERN_ERR "Processes interrupted by INIT -");
+	for_each_online_cpu(c) {
+		struct ia64_sal_os_state *s;
+		t = __va(__per_cpu_mca[c] + IA64_MCA_CPU_INIT_STACK_OFFSET);
+		s = (struct ia64_sal_os_state *)((char *)t + MCA_SOS_OFFSET);
+		g = s->prev_task;
+		if (g) {
+			if (g->pid)
+				printk(" %d", g->pid);
+			else
+				printk(" %d (cpu %d task 0x%p)", g->pid, task_cpu(g), g);
+		}
+	}
+	printk("\n\n");
+	if (read_trylock(&tasklist_lock)) {
+		do_each_thread (g, t) {
+			printk("\nBacktrace of pid %d (%s)\n", t->pid, t->comm);
+			show_stack(t, NULL, KERN_DEFAULT);
+		} while_each_thread (g, t);
+		read_unlock(&tasklist_lock);
+	}
+	/* FIXME: This will not restore zapped printk locks. */
+	RESTORE_LOGLEVEL(console_loglevel);
+	return NOTIFY_DONE;
+}
+
+/*
+ * C portion of the OS INIT handler
+ *
+ * Called from ia64_os_init_dispatch
+ *
+ * Inputs: pointer to pt_regs where processor info was saved.  SAL/OS state for
+ * this event.  This code is used for both monarch and slave INIT events, see
+ * sos->monarch.
+ *
+ * All INIT events switch to the INIT stack and change the previous process to
+ * blocked status.  If one of the INIT events is the monarch then we are
+ * probably processing the nmi button/command.  Use the monarch cpu to dump all
+ * the processes.  The slave INIT events all spin until the monarch cpu
+ * returns.  We can also get INIT slave events for MCA, in which case the MCA
+ * process is the monarch.
+ */
+
+void
+ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
+		  struct ia64_sal_os_state *sos)
+{
+	static atomic_t slaves;
+	static atomic_t monarchs;
+	struct task_struct *previous_current;
+	int cpu = smp_processor_id();
+	struct ia64_mca_notify_die nd =
+		{ .sos = sos, .monarch_cpu = &monarch_cpu };
+
+	NOTIFY_INIT(DIE_INIT_ENTER, regs, (long)&nd, 0);
+
+	mprintk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
+		sos->proc_state_param, cpu, sos->monarch);
+	salinfo_log_wakeup(SAL_INFO_TYPE_INIT, NULL, 0, 0);
+
+	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "INIT");
+	sos->os_status = IA64_INIT_RESUME;
+
+	/* FIXME: Workaround for broken proms that drive all INIT events as
+	 * slaves.  The last slave that enters is promoted to be a monarch.
+	 * Remove this code in September 2006, that gives platforms a year to
+	 * fix their proms and get their customers updated.
+	 */
+	if (!sos->monarch && atomic_add_return(1, &slaves) == num_online_cpus()) {
+		mprintk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
+		        __func__, cpu);
+		atomic_dec(&slaves);
+		sos->monarch = 1;
+	}
+
+	/* FIXME: Workaround for broken proms that drive all INIT events as
+	 * monarchs.  Second and subsequent monarchs are demoted to slaves.
+	 * Remove this code in September 2006, that gives platforms a year to
+	 * fix their proms and get their customers updated.
+	 */
+	if (sos->monarch && atomic_add_return(1, &monarchs) > 1) {
+		mprintk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
+			       __func__, cpu);
+		atomic_dec(&monarchs);
+		sos->monarch = 0;
+	}
+
+	if (!sos->monarch) {
+		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_INIT;
+
+#ifdef CONFIG_KEXEC
+		while (monarch_cpu == -1 && !atomic_read(&kdump_in_progress))
+			udelay(1000);
+#else
+		while (monarch_cpu == -1)
+			cpu_relax();	/* spin until monarch enters */
+#endif
+
+		NOTIFY_INIT(DIE_INIT_SLAVE_ENTER, regs, (long)&nd, 1);
+		NOTIFY_INIT(DIE_INIT_SLAVE_PROCESS, regs, (long)&nd, 1);
+
+#ifdef CONFIG_KEXEC
+		while (monarch_cpu != -1 && !atomic_read(&kdump_in_progress))
+			udelay(1000);
+#else
+		while (monarch_cpu != -1)
+			cpu_relax();	/* spin until monarch leaves */
+#endif
+
+		NOTIFY_INIT(DIE_INIT_SLAVE_LEAVE, regs, (long)&nd, 1);
+
+		mprintk("Slave on cpu %d returning to normal service.\n", cpu);
+		ia64_set_curr_task(cpu, previous_current);
+		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
+		atomic_dec(&slaves);
+		return;
+	}
+
+	monarch_cpu = cpu;
+	NOTIFY_INIT(DIE_INIT_MONARCH_ENTER, regs, (long)&nd, 1);
+
+	/*
+	 * Wait for a bit.  On some machines (e.g., HP's zx2000 and zx6000, INIT can be
+	 * generated via the BMC's command-line interface, but since the console is on the
+	 * same serial line, the user will need some time to switch out of the BMC before
+	 * the dump begins.
+	 */
+	mprintk("Delaying for 5 seconds...\n");
+	udelay(5*1000000);
+	ia64_wait_for_slaves(cpu, "INIT");
+	/* If nobody intercepts DIE_INIT_MONARCH_PROCESS then we drop through
+	 * to default_monarch_init_process() above and just print all the
+	 * tasks.
+	 */
+	NOTIFY_INIT(DIE_INIT_MONARCH_PROCESS, regs, (long)&nd, 1);
+	NOTIFY_INIT(DIE_INIT_MONARCH_LEAVE, regs, (long)&nd, 1);
+
+	mprintk("\nINIT dump complete.  Monarch on cpu %d returning to normal service.\n", cpu);
+	atomic_dec(&monarchs);
+	ia64_set_curr_task(cpu, previous_current);
+	monarch_cpu = -1;
+	return;
+}
+
+static int __init
+ia64_mca_disable_cpe_polling(char *str)
+{
+	cpe_poll_enabled = 0;
+	return 1;
+}
+
+__setup("disable_cpe_poll", ia64_mca_disable_cpe_polling);
+
+/* Minimal format of the MCA/INIT stacks.  The pseudo processes that run on
+ * these stacks can never sleep, they cannot return from the kernel to user
+ * space, they do not appear in a normal ps listing.  So there is no need to
+ * format most of the fields.
+ */
+
+static void
+format_mca_init_stack(void *mca_data, unsigned long offset,
+		const char *type, int cpu)
+{
+	struct task_struct *p = (struct task_struct *)((char *)mca_data + offset);
+	struct thread_info *ti;
+	memset(p, 0, KERNEL_STACK_SIZE);
+	ti = task_thread_info(p);
+	ti->flags = _TIF_MCA_INIT;
+	ti->preempt_count = 1;
+	ti->task = p;
+	ti->cpu = cpu;
+	p->stack = ti;
+	p->state = TASK_UNINTERRUPTIBLE;
+	cpumask_set_cpu(cpu, &p->cpus_mask);
+	INIT_LIST_HEAD(&p->tasks);
+	p->parent = p->real_parent = p->group_leader = p;
+	INIT_LIST_HEAD(&p->children);
+	INIT_LIST_HEAD(&p->sibling);
+	strncpy(p->comm, type, sizeof(p->comm)-1);
+}
+
+/* Caller prevents this from being called after init */
+static void * __ref mca_bootmem(void)
+{
+	return memblock_alloc(sizeof(struct ia64_mca_cpu), KERNEL_STACK_SIZE);
+}
+
+/* Do per-CPU MCA-related initialization.  */
+void
+ia64_mca_cpu_init(void *cpu_data)
+{
+	void *pal_vaddr;
+	void *data;
+	long sz = sizeof(struct ia64_mca_cpu);
+	int cpu = smp_processor_id();
+	static int first_time = 1;
+
+	/*
+	 * Structure will already be allocated if cpu has been online,
+	 * then offlined.
+	 */
+	if (__per_cpu_mca[cpu]) {
+		data = __va(__per_cpu_mca[cpu]);
+	} else {
+		if (first_time) {
+			data = mca_bootmem();
+			first_time = 0;
+		} else
+			data = (void *)__get_free_pages(GFP_ATOMIC,
+							get_order(sz));
+		if (!data)
+			panic("Could not allocate MCA memory for cpu %d\n",
+					cpu);
+	}
+	format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, mca_stack),
+		"MCA", cpu);
+	format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, init_stack),
+		"INIT", cpu);
+	__this_cpu_write(ia64_mca_data, (__per_cpu_mca[cpu] = __pa(data)));
+
+	/*
+	 * Stash away a copy of the PTE needed to map the per-CPU page.
+	 * We may need it during MCA recovery.
+	 */
+	__this_cpu_write(ia64_mca_per_cpu_pte,
+		pte_val(mk_pte_phys(__pa(cpu_data), PAGE_KERNEL)));
+
+	/*
+	 * Also, stash away a copy of the PAL address and the PTE
+	 * needed to map it.
+	 */
+	pal_vaddr = efi_get_pal_addr();
+	if (!pal_vaddr)
+		return;
+	__this_cpu_write(ia64_mca_pal_base,
+		GRANULEROUNDDOWN((unsigned long) pal_vaddr));
+	__this_cpu_write(ia64_mca_pal_pte, pte_val(mk_pte_phys(__pa(pal_vaddr),
+							      PAGE_KERNEL)));
+}
+
+static int ia64_mca_cpu_online(unsigned int cpu)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	if (!cmc_polling_enabled)
+		ia64_mca_cmc_vector_enable(NULL);
+	local_irq_restore(flags);
+	return 0;
+}
+
+/*
+ * ia64_mca_init
+ *
+ *  Do all the system level mca specific initialization.
+ *
+ *	1. Register spinloop and wakeup request interrupt vectors
+ *
+ *	2. Register OS_MCA handler entry point
+ *
+ *	3. Register OS_INIT handler entry point
+ *
+ *  4. Initialize MCA/CMC/INIT related log buffers maintained by the OS.
+ *
+ *  Note that this initialization is done very early before some kernel
+ *  services are available.
+ *
+ *  Inputs  :   None
+ *
+ *  Outputs :   None
+ */
+void __init
+ia64_mca_init(void)
+{
+	ia64_fptr_t *init_hldlr_ptr_monarch = (ia64_fptr_t *)ia64_os_init_dispatch_monarch;
+	ia64_fptr_t *init_hldlr_ptr_slave = (ia64_fptr_t *)ia64_os_init_dispatch_slave;
+	ia64_fptr_t *mca_hldlr_ptr = (ia64_fptr_t *)ia64_os_mca_dispatch;
+	int i;
+	long rc;
+	struct ia64_sal_retval isrv;
+	unsigned long timeout = IA64_MCA_RENDEZ_TIMEOUT; /* platform specific */
+	static struct notifier_block default_init_monarch_nb = {
+		.notifier_call = default_monarch_init_process,
+		.priority = 0/* we need to notified last */
+	};
+
+	IA64_MCA_DEBUG("%s: begin\n", __func__);
+
+	/* Clear the Rendez checkin flag for all cpus */
+	for(i = 0 ; i < NR_CPUS; i++)
+		ia64_mc_info.imi_rendez_checkin[i] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
+
+	/*
+	 * Register the rendezvous spinloop and wakeup mechanism with SAL
+	 */
+
+	/* Register the rendezvous interrupt vector with SAL */
+	while (1) {
+		isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_INT,
+					      SAL_MC_PARAM_MECHANISM_INT,
+					      IA64_MCA_RENDEZ_VECTOR,
+					      timeout,
+					      SAL_MC_PARAM_RZ_ALWAYS);
+		rc = isrv.status;
+		if (rc == 0)
+			break;
+		if (rc == -2) {
+			printk(KERN_INFO "Increasing MCA rendezvous timeout from "
+				"%ld to %ld milliseconds\n", timeout, isrv.v0);
+			timeout = isrv.v0;
+			NOTIFY_MCA(DIE_MCA_NEW_TIMEOUT, NULL, timeout, 0);
+			continue;
+		}
+		printk(KERN_ERR "Failed to register rendezvous interrupt "
+		       "with SAL (status %ld)\n", rc);
+		return;
+	}
+
+	/* Register the wakeup interrupt vector with SAL */
+	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_WAKEUP,
+				      SAL_MC_PARAM_MECHANISM_INT,
+				      IA64_MCA_WAKEUP_VECTOR,
+				      0, 0);
+	rc = isrv.status;
+	if (rc) {
+		printk(KERN_ERR "Failed to register wakeup interrupt with SAL "
+		       "(status %ld)\n", rc);
+		return;
+	}
+
+	IA64_MCA_DEBUG("%s: registered MCA rendezvous spinloop and wakeup mech.\n", __func__);
+
+	ia64_mc_info.imi_mca_handler        = ia64_tpa(mca_hldlr_ptr->fp);
+	/*
+	 * XXX - disable SAL checksum by setting size to 0; should be
+	 *	ia64_tpa(ia64_os_mca_dispatch_end) - ia64_tpa(ia64_os_mca_dispatch);
+	 */
+	ia64_mc_info.imi_mca_handler_size	= 0;
+
+	/* Register the os mca handler with SAL */
+	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_MCA,
+				       ia64_mc_info.imi_mca_handler,
+				       ia64_tpa(mca_hldlr_ptr->gp),
+				       ia64_mc_info.imi_mca_handler_size,
+				       0, 0, 0)))
+	{
+		printk(KERN_ERR "Failed to register OS MCA handler with SAL "
+		       "(status %ld)\n", rc);
+		return;
+	}
+
+	IA64_MCA_DEBUG("%s: registered OS MCA handler with SAL at 0x%lx, gp = 0x%lx\n", __func__,
+		       ia64_mc_info.imi_mca_handler, ia64_tpa(mca_hldlr_ptr->gp));
+
+	/*
+	 * XXX - disable SAL checksum by setting size to 0, should be
+	 * size of the actual init handler in mca_asm.S.
+	 */
+	ia64_mc_info.imi_monarch_init_handler		= ia64_tpa(init_hldlr_ptr_monarch->fp);
+	ia64_mc_info.imi_monarch_init_handler_size	= 0;
+	ia64_mc_info.imi_slave_init_handler		= ia64_tpa(init_hldlr_ptr_slave->fp);
+	ia64_mc_info.imi_slave_init_handler_size	= 0;
+
+	IA64_MCA_DEBUG("%s: OS INIT handler at %lx\n", __func__,
+		       ia64_mc_info.imi_monarch_init_handler);
+
+	/* Register the os init handler with SAL */
+	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_INIT,
+				       ia64_mc_info.imi_monarch_init_handler,
+				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
+				       ia64_mc_info.imi_monarch_init_handler_size,
+				       ia64_mc_info.imi_slave_init_handler,
+				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
+				       ia64_mc_info.imi_slave_init_handler_size)))
+	{
+		printk(KERN_ERR "Failed to register m/s INIT handlers with SAL "
+		       "(status %ld)\n", rc);
+		return;
+	}
+	if (register_die_notifier(&default_init_monarch_nb)) {
+		printk(KERN_ERR "Failed to register default monarch INIT process\n");
+		return;
+	}
+
+	IA64_MCA_DEBUG("%s: registered OS INIT handler with SAL\n", __func__);
+
+	/* Initialize the areas set aside by the OS to buffer the
+	 * platform/processor error states for MCA/INIT/CMC
+	 * handling.
+	 */
+	ia64_log_init(SAL_INFO_TYPE_MCA);
+	ia64_log_init(SAL_INFO_TYPE_INIT);
+	ia64_log_init(SAL_INFO_TYPE_CMC);
+	ia64_log_init(SAL_INFO_TYPE_CPE);
+
+	mca_init = 1;
+	printk(KERN_INFO "MCA related initialization done\n");
+}
+
+
+/*
+ * These pieces cannot be done in ia64_mca_init() because it is called before
+ * early_irq_init() which would wipe out our percpu irq registrations. But we
+ * cannot leave them until ia64_mca_late_init() because by then all the other
+ * processors have been brought online and have set their own CMC vectors to
+ * point at a non-existant action. Called from arch_early_irq_init().
+ */
+void __init ia64_mca_irq_init(void)
+{
+	/*
+	 *  Configure the CMCI/P vector and handler. Interrupts for CMC are
+	 *  per-processor, so AP CMC interrupts are setup in smp_callin() (smpboot.c).
+	 */
+	register_percpu_irq(IA64_CMC_VECTOR, ia64_mca_cmc_int_handler, 0,
+			    "cmc_hndlr");
+	register_percpu_irq(IA64_CMCP_VECTOR, ia64_mca_cmc_int_caller, 0,
+			    "cmc_poll");
+	ia64_mca_cmc_vector_setup();       /* Setup vector on BSP */
+
+	/* Setup the MCA rendezvous interrupt vector */
+	register_percpu_irq(IA64_MCA_RENDEZ_VECTOR, ia64_mca_rendez_int_handler,
+			    0, "mca_rdzv");
+
+	/* Setup the MCA wakeup interrupt vector */
+	register_percpu_irq(IA64_MCA_WAKEUP_VECTOR, ia64_mca_wakeup_int_handler,
+			    0, "mca_wkup");
+
+	/* Setup the CPEI/P handler */
+	register_percpu_irq(IA64_CPEP_VECTOR, ia64_mca_cpe_int_caller, 0,
+			    "cpe_poll");
+}
+
+/*
+ * ia64_mca_late_init
+ *
+ *	Opportunity to setup things that require initialization later
+ *	than ia64_mca_init.  Setup a timer to poll for CPEs if the
+ *	platform doesn't support an interrupt driven mechanism.
+ *
+ *  Inputs  :   None
+ *  Outputs :   Status
+ */
+static int __init
+ia64_mca_late_init(void)
+{
+	if (!mca_init)
+		return 0;
+
+	/* Setup the CMCI/P vector and handler */
+	timer_setup(&cmc_poll_timer, ia64_mca_cmc_poll, 0);
+
+	/* Unmask/enable the vector */
+	cmc_polling_enabled = 0;
+	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "ia64/mca:online",
+			  ia64_mca_cpu_online, NULL);
+	IA64_MCA_DEBUG("%s: CMCI/P setup and enabled.\n", __func__);
+
+	/* Setup the CPEI/P vector and handler */
+	cpe_vector = acpi_request_vector(ACPI_INTERRUPT_CPEI);
+	timer_setup(&cpe_poll_timer, ia64_mca_cpe_poll, 0);
+
+	{
+		unsigned int irq;
+
+		if (cpe_vector >= 0) {
+			/* If platform supports CPEI, enable the irq. */
+			irq = local_vector_to_irq(cpe_vector);
+			if (irq > 0) {
+				cpe_poll_enabled = 0;
+				irq_set_status_flags(irq, IRQ_PER_CPU);
+				if (request_irq(irq, ia64_mca_cpe_int_handler,
+						0, "cpe_hndlr", NULL))
+					pr_err("Failed to register cpe_hndlr interrupt\n");
+				ia64_cpe_irq = irq;
+				ia64_mca_register_cpev(cpe_vector);
+				IA64_MCA_DEBUG("%s: CPEI/P setup and enabled.\n",
+					__func__);
+				return 0;
+			}
+			printk(KERN_ERR "%s: Failed to find irq for CPE "
+					"interrupt handler, vector %d\n",
+					__func__, cpe_vector);
+		}
+		/* If platform doesn't support CPEI, get the timer going. */
+		if (cpe_poll_enabled) {
+			ia64_mca_cpe_poll(0UL);
+			IA64_MCA_DEBUG("%s: CPEP setup and enabled.\n", __func__);
+		}
+	}
+
+	return 0;
+}
+
+device_initcall(ia64_mca_late_init);