Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
  ACPI: IA64: fix %ll build warnings
  ACPI: IA64: fix allnoconfig build
  ACPI: Only use IPI on known broken machines (AMD, Dothan/BaniasPentium M)
  ACPI: ibm-acpi: allow module to load when acpi notifiers can't be set (v2)
  ACPI: parse 2nd MADT by default
  ACPICA: revert "acpi_serialize" changes
  sony-laptop: MAINTAINERS fix entry, add L: and W:
  ACPI: resolve HP nx6125 S3 immediate wakeup regression
  ACPI: Add support to parse 2nd MADT

13 files changed, 191 insertions, 125 deletions

diff --git a/drivers/acpi/events/evmisc.c b/drivers/acpi/events/evmisc.c
index 3a799b9b5df..cae786ca860 100644
--- a/drivers/acpi/events/evmisc.c
+++ b/drivers/acpi/events/evmisc.c
@@ -196,11 +196,15 @@ acpi_ev_queue_notify_request(struct acpi_namespace_node * node,
 		notify_info->notify.value = (u16) notify_value;
 		notify_info->notify.handler_obj = handler_obj;
 
-		acpi_ex_relinquish_interpreter();
+		acpi_ex_exit_interpreter();
 
 		acpi_ev_notify_dispatch(notify_info);
 
-		acpi_ex_reacquire_interpreter();
+		status = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+
 	}
 
 	if (!handler_obj) {
diff --git a/drivers/acpi/events/evregion.c b/drivers/acpi/events/evregion.c
index e99f0c435a4..96b0e843174 100644
--- a/drivers/acpi/events/evregion.c
+++ b/drivers/acpi/events/evregion.c
@@ -291,6 +291,7 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 			       u32 bit_width, acpi_integer * value)
 {
 	acpi_status status;
+	acpi_status status2;
 	acpi_adr_space_handler handler;
 	acpi_adr_space_setup region_setup;
 	union acpi_operand_object *handler_desc;
@@ -344,7 +345,7 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 		 * setup will potentially execute control methods
 		 * (e.g., _REG method for this region)
 		 */
-		acpi_ex_relinquish_interpreter();
+		acpi_ex_exit_interpreter();
 
 		status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
 				      handler_desc->address_space.context,
@@ -352,7 +353,10 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 
 		/* Re-enter the interpreter */
 
-		acpi_ex_reacquire_interpreter();
+		status2 = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status2)) {
+			return_ACPI_STATUS(status2);
+		}
 
 		/* Check for failure of the Region Setup */
 
@@ -405,7 +409,7 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 		 * exit the interpreter because the handler *might* block -- we don't
 		 * know what it will do, so we can't hold the lock on the intepreter.
 		 */
-		acpi_ex_relinquish_interpreter();
+		acpi_ex_exit_interpreter();
 	}
 
 	/* Call the handler */
@@ -426,7 +430,10 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 		 * We just returned from a non-default handler, we must re-enter the
 		 * interpreter
 		 */
-		acpi_ex_reacquire_interpreter();
+		status2 = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status2)) {
+			return_ACPI_STATUS(status2);
+		}
 	}
 
 	return_ACPI_STATUS(status);
diff --git a/drivers/acpi/events/evxface.c b/drivers/acpi/events/evxface.c
index 685a103a358..a3379bafa67 100644
--- a/drivers/acpi/events/evxface.c
+++ b/drivers/acpi/events/evxface.c
@@ -768,9 +768,11 @@ acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 		return (AE_BAD_PARAMETER);
 	}
 
-	/* Must lock interpreter to prevent race conditions */
+	status = acpi_ex_enter_interpreter();
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
 
-	acpi_ex_enter_interpreter();
 	status = acpi_ev_acquire_global_lock(timeout);
 	acpi_ex_exit_interpreter();
 
diff --git a/drivers/acpi/executer/excreate.c b/drivers/acpi/executer/excreate.c
index 7c38528a7e8..ae97812681a 100644
--- a/drivers/acpi/executer/excreate.c
+++ b/drivers/acpi/executer/excreate.c
@@ -583,7 +583,10 @@ acpi_ex_create_method(u8 * aml_start,
 	 * Get the sync_level. If method is serialized, a mutex will be
 	 * created for this method when it is parsed.
 	 */
-	if (method_flags & AML_METHOD_SERIALIZED) {
+	if (acpi_gbl_all_methods_serialized) {
+		obj_desc->method.sync_level = 0;
+		obj_desc->method.method_flags |= AML_METHOD_SERIALIZED;
+	} else if (method_flags & AML_METHOD_SERIALIZED) {
 		/*
 		 * ACPI 1.0: sync_level = 0
 		 * ACPI 2.0: sync_level = sync_level in method declaration
diff --git a/drivers/acpi/executer/exsystem.c b/drivers/acpi/executer/exsystem.c
index 9460baff303..b2edf620ba8 100644
--- a/drivers/acpi/executer/exsystem.c
+++ b/drivers/acpi/executer/exsystem.c
@@ -66,6 +66,7 @@ ACPI_MODULE_NAME("exsystem")
 acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
 {
 	acpi_status status;
+	acpi_status status2;
 
 	ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
 
@@ -78,7 +79,7 @@ acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
 
 		/* We must wait, so unlock the interpreter */
 
-		acpi_ex_relinquish_interpreter();
+		acpi_ex_exit_interpreter();
 
 		status = acpi_os_wait_semaphore(semaphore, 1, timeout);
 
@@ -88,7 +89,13 @@ acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
 
 		/* Reacquire the interpreter */
 
-		acpi_ex_reacquire_interpreter();
+		status2 = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status2)) {
+
+			/* Report fatal error, could not acquire interpreter */
+
+			return_ACPI_STATUS(status2);
+		}
 	}
 
 	return_ACPI_STATUS(status);
@@ -112,6 +119,7 @@ acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
 acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
 {
 	acpi_status status;
+	acpi_status status2;
 
 	ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
 
@@ -124,7 +132,7 @@ acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
 
 		/* We must wait, so unlock the interpreter */
 
-		acpi_ex_relinquish_interpreter();
+		acpi_ex_exit_interpreter();
 
 		status = acpi_os_acquire_mutex(mutex, timeout);
 
@@ -134,7 +142,13 @@ acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
 
 		/* Reacquire the interpreter */
 
-		acpi_ex_reacquire_interpreter();
+		status2 = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status2)) {
+
+			/* Report fatal error, could not acquire interpreter */
+
+			return_ACPI_STATUS(status2);
+		}
 	}
 
 	return_ACPI_STATUS(status);
@@ -195,18 +209,20 @@ acpi_status acpi_ex_system_do_stall(u32 how_long)
 
 acpi_status acpi_ex_system_do_suspend(acpi_integer how_long)
 {
+	acpi_status status;
+
 	ACPI_FUNCTION_ENTRY();
 
 	/* Since this thread will sleep, we must release the interpreter */
 
-	acpi_ex_relinquish_interpreter();
+	acpi_ex_exit_interpreter();
 
 	acpi_os_sleep(how_long);
 
 	/* And now we must get the interpreter again */
 
-	acpi_ex_reacquire_interpreter();
-	return (AE_OK);
+	status = acpi_ex_enter_interpreter();
+	return (status);
 }
 
 /*******************************************************************************
diff --git a/drivers/acpi/executer/exutils.c b/drivers/acpi/executer/exutils.c
index 6b0aeccbb69..aea461f3a48 100644
--- a/drivers/acpi/executer/exutils.c
+++ b/drivers/acpi/executer/exutils.c
@@ -76,15 +76,14 @@ static u32 acpi_ex_digits_needed(acpi_integer value, u32 base);
  *
  * PARAMETERS:  None
  *
- * RETURN:      None
+ * RETURN:      Status
  *
- * DESCRIPTION: Enter the interpreter execution region. Failure to enter
- *              the interpreter region is a fatal system error. Used in
- *              conjunction with exit_interpreter.
+ * DESCRIPTION: Enter the interpreter execution region.  Failure to enter
+ *              the interpreter region is a fatal system error
  *
  ******************************************************************************/
 
-void acpi_ex_enter_interpreter(void)
+acpi_status acpi_ex_enter_interpreter(void)
 {
 	acpi_status status;
 
@@ -92,42 +91,10 @@ void acpi_ex_enter_interpreter(void)
 
 	status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
 	if (ACPI_FAILURE(status)) {
-		ACPI_ERROR((AE_INFO,
-			    "Could not acquire AML Interpreter mutex"));
+		ACPI_ERROR((AE_INFO, "Could not acquire interpreter mutex"));
 	}
 
-	return_VOID;
-}
-
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ex_reacquire_interpreter
- *
- * PARAMETERS:  None
- *
- * RETURN:      None
- *
- * DESCRIPTION: Reacquire the interpreter execution region from within the
- *              interpreter code. Failure to enter the interpreter region is a
- *              fatal system error. Used in  conjuction with
- *              relinquish_interpreter
- *
- ******************************************************************************/
-
-void acpi_ex_reacquire_interpreter(void)
-{
-	ACPI_FUNCTION_TRACE(ex_reacquire_interpreter);
-
-	/*
-	 * If the global serialized flag is set, do not release the interpreter,
-	 * since it was not actually released by acpi_ex_relinquish_interpreter.
-	 * This forces the interpreter to be single threaded.
-	 */
-	if (!acpi_gbl_all_methods_serialized) {
-		acpi_ex_enter_interpreter();
-	}
-
-	return_VOID;
+	return_ACPI_STATUS(status);
 }
 
 /*******************************************************************************
@@ -138,9 +105,17 @@ void acpi_ex_reacquire_interpreter(void)
  *
  * RETURN:      None
  *
- * DESCRIPTION: Exit the interpreter execution region. This is the top level
- *              routine used to exit the interpreter when all processing has
- *              been completed.
+ * DESCRIPTION: Exit the interpreter execution region
+ *
+ * Cases where the interpreter is unlocked:
+ *      1) Completion of the execution of a control method
+ *      2) Method blocked on a Sleep() AML opcode
+ *      3) Method blocked on an Acquire() AML opcode
+ *      4) Method blocked on a Wait() AML opcode
+ *      5) Method blocked to acquire the global lock
+ *      6) Method blocked to execute a serialized control method that is
+ *          already executing
+ *      7) About to invoke a user-installed opregion handler
  *
  ******************************************************************************/
 
@@ -152,46 +127,7 @@ void acpi_ex_exit_interpreter(void)
 
 	status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
 	if (ACPI_FAILURE(status)) {
-		ACPI_ERROR((AE_INFO,
-			    "Could not release AML Interpreter mutex"));
-	}
-
-	return_VOID;
-}
-
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ex_relinquish_interpreter
- *
- * PARAMETERS:  None
- *
- * RETURN:      None
- *
- * DESCRIPTION: Exit the interpreter execution region, from within the
- *              interpreter - before attempting an operation that will possibly
- *              block the running thread.
- *
- * Cases where the interpreter is unlocked internally
- *      1) Method to be blocked on a Sleep() AML opcode
- *      2) Method to be blocked on an Acquire() AML opcode
- *      3) Method to be blocked on a Wait() AML opcode
- *      4) Method to be blocked to acquire the global lock
- *      5) Method to be blocked waiting to execute a serialized control method
- *          that is currently executing
- *      6) About to invoke a user-installed opregion handler
- *
- ******************************************************************************/
-
-void acpi_ex_relinquish_interpreter(void)
-{
-	ACPI_FUNCTION_TRACE(ex_relinquish_interpreter);
-
-	/*
-	 * If the global serialized flag is set, do not release the interpreter.
-	 * This forces the interpreter to be single threaded.
-	 */
-	if (!acpi_gbl_all_methods_serialized) {
-		acpi_ex_exit_interpreter();
+		ACPI_ERROR((AE_INFO, "Could not release interpreter mutex"));
 	}
 
 	return_VOID;
@@ -205,8 +141,8 @@ void acpi_ex_relinquish_interpreter(void)
  *
  * RETURN:      none
  *
- * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
- *              32-bit, as determined by the revision of the DSDT.
+ * DESCRIPTION: Truncate a number to 32-bits if the currently executing method
+ *              belongs to a 32-bit ACPI table.
  *
  ******************************************************************************/
 
diff --git a/drivers/acpi/hardware/hwsleep.c b/drivers/acpi/hardware/hwsleep.c
index 8fa93125fd4..c84b1faba28 100644
--- a/drivers/acpi/hardware/hwsleep.c
+++ b/drivers/acpi/hardware/hwsleep.c
@@ -300,6 +300,11 @@ acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
 	/*
 	 * 2) Enable all wakeup GPEs
 	 */
+	status = acpi_hw_disable_all_gpes();
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
+
 	acpi_gbl_system_awake_and_running = FALSE;
 
 	status = acpi_hw_enable_all_wakeup_gpes();
diff --git a/drivers/acpi/ibm_acpi.c b/drivers/acpi/ibm_acpi.c
index 36901362fd2..dc1096608f4 100644
--- a/drivers/acpi/ibm_acpi.c
+++ b/drivers/acpi/ibm_acpi.c
@@ -2507,7 +2507,7 @@ static int __init setup_notify(struct ibm_struct *ibm)
 	ret = acpi_bus_get_device(*ibm->handle, &ibm->device);
 	if (ret < 0) {
 		printk(IBM_ERR "%s device not present\n", ibm->name);
-		return 0;
+		return -ENODEV;
 	}
 
 	acpi_driver_data(ibm->device) = ibm;
@@ -2516,8 +2516,13 @@ static int __init setup_notify(struct ibm_struct *ibm)
 	status = acpi_install_notify_handler(*ibm->handle, ibm->type,
 					     dispatch_notify, ibm);
 	if (ACPI_FAILURE(status)) {
-		printk(IBM_ERR "acpi_install_notify_handler(%s) failed: %d\n",
-		       ibm->name, status);
+		if (status == AE_ALREADY_EXISTS) {
+			printk(IBM_NOTICE "another device driver is already handling %s events\n",
+				ibm->name);
+		} else {
+			printk(IBM_ERR "acpi_install_notify_handler(%s) failed: %d\n",
+				ibm->name, status);
+		}
 		return -ENODEV;
 	}
 	ibm->notify_installed = 1;
@@ -2553,6 +2558,8 @@ static int __init register_driver(struct ibm_struct *ibm)
 	return ret;
 }
 
+static void ibm_exit(struct ibm_struct *ibm);
+
 static int __init ibm_init(struct ibm_struct *ibm)
 {
 	int ret;
@@ -2594,6 +2601,12 @@ static int __init ibm_init(struct ibm_struct *ibm)
 
 	if (ibm->notify) {
 		ret = setup_notify(ibm);
+		if (ret == -ENODEV) {
+			printk(IBM_NOTICE "disabling subdriver %s\n",
+				ibm->name);
+			ibm_exit(ibm);
+			return 0;
+		}
 		if (ret < 0)
 			return ret;
 	}
diff --git a/drivers/acpi/namespace/nseval.c b/drivers/acpi/namespace/nseval.c
index aa6370c67ec..26fd0dd6953 100644
--- a/drivers/acpi/namespace/nseval.c
+++ b/drivers/acpi/namespace/nseval.c
@@ -154,7 +154,11 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
 		 * Execute the method via the interpreter. The interpreter is locked
 		 * here before calling into the AML parser
 		 */
-		acpi_ex_enter_interpreter();
+		status = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+
 		status = acpi_ps_execute_method(info);
 		acpi_ex_exit_interpreter();
 	} else {
@@ -178,7 +182,10 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
 		 * resolution, we must lock it because we could access an opregion.
 		 * The opregion access code assumes that the interpreter is locked.
 		 */
-		acpi_ex_enter_interpreter();
+		status = acpi_ex_enter_interpreter();
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
 
 		/* Function has a strange interface */
 
diff --git a/drivers/acpi/namespace/nsinit.c b/drivers/acpi/namespace/nsinit.c
index 33db2241044..c4ab615f77f 100644
--- a/drivers/acpi/namespace/nsinit.c
+++ b/drivers/acpi/namespace/nsinit.c
@@ -214,7 +214,7 @@ acpi_ns_init_one_object(acpi_handle obj_handle,
 			u32 level, void *context, void **return_value)
 {
 	acpi_object_type type;
-	acpi_status status = AE_OK;
+	acpi_status status;
 	struct acpi_init_walk_info *info =
 	    (struct acpi_init_walk_info *)context;
 	struct acpi_namespace_node *node =
@@ -268,7 +268,10 @@ acpi_ns_init_one_object(acpi_handle obj_handle,
 	/*
 	 * Must lock the interpreter before executing AML code
 	 */
-	acpi_ex_enter_interpreter();
+	status = acpi_ex_enter_interpreter();
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
 
 	/*
 	 * Each of these types can contain executable AML code within the
diff --git a/drivers/acpi/namespace/nsxfeval.c b/drivers/acpi/namespace/nsxfeval.c
index 7ac6ace5005..8904d0fae6a 100644
--- a/drivers/acpi/namespace/nsxfeval.c
+++ b/drivers/acpi/namespace/nsxfeval.c
@@ -170,6 +170,7 @@ acpi_evaluate_object(acpi_handle handle,
 		     struct acpi_buffer *return_buffer)
 {
 	acpi_status status;
+	acpi_status status2;
 	struct acpi_evaluate_info *info;
 	acpi_size buffer_space_needed;
 	u32 i;
@@ -328,12 +329,14 @@ acpi_evaluate_object(acpi_handle handle,
 		 * Delete the internal return object. NOTE: Interpreter must be
 		 * locked to avoid race condition.
 		 */
-		acpi_ex_enter_interpreter();
+		status2 = acpi_ex_enter_interpreter();
+		if (ACPI_SUCCESS(status2)) {
 
-		/* Remove one reference on the return object (should delete it) */
+			/* Remove one reference on the return object (should delete it) */
 
-		acpi_ut_remove_reference(info->return_object);
-		acpi_ex_exit_interpreter();
+			acpi_ut_remove_reference(info->return_object);
+			acpi_ex_exit_interpreter();
+		}
 	}
 
       cleanup:
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 60773005b8a..562124ed785 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -89,6 +89,12 @@ module_param(nocst, uint, 0000);
 static unsigned int bm_history __read_mostly =
     (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1));
 module_param(bm_history, uint, 0644);
+
+static unsigned use_ipi = 2;
+module_param(use_ipi, uint, 0644);
+MODULE_PARM_DESC(use_ipi, "IPI (vs. LAPIC) irqs for not waking up from C2/C3"
+		 " machines. 0=apic, 1=ipi, 2=auto\n");
+
 /* --------------------------------------------------------------------------
                                 Power Management
    -------------------------------------------------------------------------- */
@@ -260,9 +266,8 @@ static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
 
 /*
  * Some BIOS implementations switch to C3 in the published C2 state.
- * This seems to be a common problem on AMD boxen, but other vendors
- * are affected too. We pick the most conservative approach: we assume
- * that the local APIC stops in both C2 and C3.
+ * This seems to be a common problem on AMD boxen and Intel Dothan/Banias
+ * Pentium M machines.
  */
 static void acpi_timer_check_state(int state, struct acpi_processor *pr,
 				   struct acpi_processor_cx *cx)
@@ -276,8 +281,17 @@ static void acpi_timer_check_state(int state, struct acpi_processor *pr,
 	if (pwr->timer_broadcast_on_state < state)
 		return;
 
-	if (cx->type >= ACPI_STATE_C2)
-		pr->power.timer_broadcast_on_state = state;
+	if (cx->type >= ACPI_STATE_C2) {
+		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+			pr->power.timer_broadcast_on_state = state;
+		else if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+			  boot_cpu_data.x86 == 6) &&
+			 (boot_cpu_data.x86_model == 13 ||
+			  boot_cpu_data.x86_model == 9))
+		{
+			pr->power.timer_broadcast_on_state = state;
+		}
+	}
 }
 
 static void acpi_propagate_timer_broadcast(struct acpi_processor *pr)
@@ -292,10 +306,16 @@ static void acpi_propagate_timer_broadcast(struct acpi_processor *pr)
 #else
 	cpumask_t mask = cpumask_of_cpu(pr->id);
 
-	if (pr->power.timer_broadcast_on_state < INT_MAX)
+	if (use_ipi == 0)
 		on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1);
-	else
+	else if (use_ipi == 1)
 		on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1);
+	else {
+		if (pr->power.timer_broadcast_on_state < INT_MAX)
+			on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1);
+		else
+			on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1);
+	}
 #endif
 }
 
@@ -1013,13 +1033,13 @@ static int acpi_processor_power_verify(struct acpi_processor *pr)
 
 		case ACPI_STATE_C2:
 			acpi_processor_power_verify_c2(cx);
-			if (cx->valid)
+			if (cx->valid && use_ipi != 0 && use_ipi != 1)
 				acpi_timer_check_state(i, pr, cx);
 			break;
 
 		case ACPI_STATE_C3:
 			acpi_processor_power_verify_c3(pr, cx);
-			if (cx->valid)
+			if (cx->valid && use_ipi != 0 && use_ipi != 1)
 				acpi_timer_check_state(i, pr, cx);
 			break;
 		}
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index 849e2c36180..96792a6cc16 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -42,7 +42,9 @@ static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
 
 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
 
-void acpi_table_print_madt_entry(struct acpi_subtable_header * header)
+static int acpi_apic_instance __initdata = 2;
+
+void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 {
 	if (!header)
 		return;
@@ -183,8 +185,10 @@ acpi_table_parse_entries(char *id,
 	if (!handler)
 		return -EINVAL;
 
-	/* Locate the table (if exists). There should only be one. */
-	acpi_get_table(id, 0, &table_header);
+	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
+		acpi_get_table(id, acpi_apic_instance, &table_header);
+	else
+		acpi_get_table(id, 0, &table_header);
 
 	if (!table_header) {
 		printk(KERN_WARNING PREFIX "%4.4s not present\n", id);
@@ -237,10 +241,15 @@ acpi_table_parse_madt(enum acpi_madt_type id,
 int __init acpi_table_parse(char *id, acpi_table_handler handler)
 {
 	struct acpi_table_header *table = NULL;
+
 	if (!handler)
 		return -EINVAL;
 
-	acpi_get_table(id, 0, &table);
+	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
+		acpi_get_table(id, acpi_apic_instance, &table);
+	else
+		acpi_get_table(id, 0, &table);
+
 	if (table) {
 		handler(table);
 		return 0;
@@ -248,6 +257,31 @@ int __init acpi_table_parse(char *id, acpi_table_handler handler)
 		return 1;
 }
 
+/* 
+ * The BIOS is supposed to supply a single APIC/MADT,
+ * but some report two.  Provide a knob to use either.
+ * (don't you wish instance 0 and 1 were not the same?)
+ */
+static void __init check_multiple_madt(void)
+{
+	struct acpi_table_header *table = NULL;
+
+	acpi_get_table(ACPI_SIG_MADT, 2, &table);
+	if (table) {
+		printk(KERN_WARNING PREFIX
+		       "BIOS bug: multiple APIC/MADT found,"
+		       " using %d\n", acpi_apic_instance);
+		printk(KERN_WARNING PREFIX
+		       "If \"acpi_apic_instance=%d\" works better, "
+		       "notify linux-acpi@vger.kernel.org\n",
+		       acpi_apic_instance ? 0 : 2);
+
+	} else
+		acpi_apic_instance = 0;
+
+	return;
+}
+
 /*
  * acpi_table_init()
  *
@@ -257,9 +291,22 @@ int __init acpi_table_parse(char *id, acpi_table_handler handler)
  * result: sdt_entry[] is initialized
  */
 
-
 int __init acpi_table_init(void)
 {
 	acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
+	check_multiple_madt();
+	return 0;
+}
+
+static int __init acpi_parse_apic_instance(char *str)
+{
+
+	acpi_apic_instance = simple_strtoul(str, NULL, 0);
+
+	printk(KERN_NOTICE PREFIX "Shall use APIC/MADT table %d\n",
+	       acpi_apic_instance);
+
 	return 0;
 }
+
+early_param("acpi_apic_instance", acpi_parse_apic_instance);