Merge tag 'acpi-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These eliminate significant AML processing overhead related to using
  operation regions in system memory, update the ACPICA code in the
  kernel to upstream revision 20200717 (including a fix to prevent
  operation region reference counts from overflowing in some cases),
  remove the last bits of the (long deprecated) ACPI procfs interface
  and do some assorted cleanups.

  Specifics:

   - Eliminate significant AML processing overhead related to using
     operation regions in system memory by reworking the management of
     memory mappings in the ACPI code to defer unmap operations (to do
     them outside of the ACPICA locks, among other things) and making
     the memory operation reagion handler avoid releasing memory
     mappings created by it too early (Rafael Wysocki).

   - Update the ACPICA code in the kernel to upstream revision 20200717:

       * Prevent operation region reference counts from overflowing in
         some cases (Erik Kaneda).

       * Replace one-element array with flexible-array (Gustavo A. R.
         Silva).

   - Fix ACPI PCI hotplug reference counting (Rafael Wysocki).

   - Drop last bits of the ACPI procfs interface (Thomas Renninger).

   - Drop some redundant checks from the code parsing ACPI tables
     related to NUMA (Hanjun Guo).

   - Avoid redundant object evaluation in the ACPI device properties
     handling code (Heikki Krogerus).

   - Avoid unecessary memory overhead related to storing the signatures
     of the ACPI tables recognized by the kernel (Ard Biesheuvel).

   - Add missing newline characters when printing module parameter
     values in some places (Xiongfeng Wang).

   - Update the link to the ACPI specifications in some places (Tiezhu
     Yang).

   - Use the fallthrough pseudo-keyword in the ACPI code (Gustavo A. R.
     Silva).

   - Drop redundant variable initialization from the APEI code (Colin
     Ian King).

   - Drop uninitialized_var() from the ACPI PAD driver (Jason Yan).

   - Replace HTTP links with HTTPS ones in the ACPI code (Alexander A.
     Klimov)"

* tag 'acpi-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (22 commits)
  ACPI: APEI: remove redundant assignment to variable rc
  ACPI: NUMA: Remove the useless 'node >= MAX_NUMNODES' check
  ACPI: NUMA: Remove the useless sub table pointer check
  ACPI: tables: Remove the duplicated checks for acpi_parse_entries_array()
  ACPICA: Update version to 20200717
  ACPICA: Do not increment operation_region reference counts for field units
  ACPICA: Replace one-element array with flexible-array
  ACPI: Replace HTTP links with HTTPS ones
  ACPI: Use valid link to the ACPI specification
  ACPI: OSL: Clean up the removal of unused memory mappings
  ACPI: OSL: Use deferred unmapping in acpi_os_unmap_iomem()
  ACPI: OSL: Use deferred unmapping in acpi_os_unmap_generic_address()
  ACPICA: Preserve memory opregion mappings
  ACPI: OSL: Implement deferred unmapping of ACPI memory
  ACPI: Use fallthrough pseudo-keyword
  PCI: hotplug: ACPI: Fix context refcounting in acpiphp_grab_context()
  ACPI: tables: avoid relocations for table signature array
  ACPI: PAD: Eliminate usage of uninitialized_var() macro
  ACPI: sysfs: add newlines when printing module parameters
  ACPI: EC: add newline when printing 'ec_event_clearing' module parameter
  ...

38 files changed, 167 insertions, 620 deletions

diff --git a/Documentation/firmware-guide/acpi/DSD-properties-rules.rst b/Documentation/firmware-guide/acpi/DSD-properties-rules.rst
index 4306f29b6103..8b2d8d0864c2 100644
--- a/Documentation/firmware-guide/acpi/DSD-properties-rules.rst
+++ b/Documentation/firmware-guide/acpi/DSD-properties-rules.rst
@@ -96,5 +96,5 @@ contents.
 References
 ==========
 
-.. [1] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf
-.. [2] http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf
+.. [1] https://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf
+.. [2] https://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf
diff --git a/Documentation/firmware-guide/acpi/dsd/data-node-references.rst b/Documentation/firmware-guide/acpi/dsd/data-node-references.rst
index febccbc5689d..9b17dc77d18c 100644
--- a/Documentation/firmware-guide/acpi/dsd/data-node-references.rst
+++ b/Documentation/firmware-guide/acpi/dsd/data-node-references.rst
@@ -85,9 +85,9 @@ References
 ==========
 
 [1] Hierarchical Data Extension UUID For _DSD.
-<http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>,
+<https://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>,
 referenced 2018-07-17.
 
 [2] Device Properties UUID For _DSD.
-<http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,
+<https://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,
 referenced 2016-10-04.
diff --git a/Documentation/firmware-guide/acpi/dsd/graph.rst b/Documentation/firmware-guide/acpi/dsd/graph.rst
index 1a6ce7afba5e..7072db801aeb 100644
--- a/Documentation/firmware-guide/acpi/dsd/graph.rst
+++ b/Documentation/firmware-guide/acpi/dsd/graph.rst
@@ -154,23 +154,23 @@ References
 ==========
 
 [1] _DSD (Device Specific Data) Implementation Guide.
-    http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel-1_1.htm,
+    https://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel-1_1.htm,
     referenced 2016-10-03.
 
-[2] Devicetree. http://www.devicetree.org, referenced 2016-10-03.
+[2] Devicetree. https://www.devicetree.org, referenced 2016-10-03.
 
 [3] Documentation/devicetree/bindings/graph.txt
 
 [4] Device Properties UUID For _DSD.
-    http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf,
+    https://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf,
     referenced 2016-10-04.
 
 [5] Hierarchical Data Extension UUID For _DSD.
-    http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf,
+    https://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf,
     referenced 2016-10-04.
 
 [6] Advanced Configuration and Power Interface Specification.
-    http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf,
+    https://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf,
     referenced 2016-10-04.
 
 [7] _DSD Device Properties Usage Rules.
diff --git a/Documentation/firmware-guide/acpi/dsd/leds.rst b/Documentation/firmware-guide/acpi/dsd/leds.rst
index 946efe2b2936..aba1e9abfeeb 100644
--- a/Documentation/firmware-guide/acpi/dsd/leds.rst
+++ b/Documentation/firmware-guide/acpi/dsd/leds.rst
@@ -90,7 +90,7 @@ where
 References
 ==========
 
-[1] Device tree. <URL:http://www.devicetree.org>, referenced 2019-02-21.
+[1] Device tree. <URL:https://www.devicetree.org>, referenced 2019-02-21.
 
 [2] Advanced Configuration and Power Interface Specification.
     <URL:https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf>,
@@ -101,11 +101,11 @@ References
 [4] Documentation/devicetree/bindings/media/video-interfaces.txt
 
 [5] Device Properties UUID For _DSD.
-    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,
+    <URL:https://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>,
     referenced 2019-02-21.
 
 [6] Hierarchical Data Extension UUID For _DSD.
-    <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>,
+    <URL:https://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>,
     referenced 2019-02-21.
 
 [7] Documentation/firmware-guide/acpi/dsd/data-node-references.rst
diff --git a/Documentation/firmware-guide/acpi/lpit.rst b/Documentation/firmware-guide/acpi/lpit.rst
index aca928fab027..37922a903573 100644
--- a/Documentation/firmware-guide/acpi/lpit.rst
+++ b/Documentation/firmware-guide/acpi/lpit.rst
@@ -7,7 +7,7 @@ Low Power Idle Table (LPIT)
 To enumerate platform Low Power Idle states, Intel platforms are using
 “Low Power Idle Table” (LPIT). More details about this table can be
 downloaded from:
-http://www.uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf
+https://www.uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf
 
 Residencies for each low power state can be read via FFH
 (Function fixed hardware) or a memory mapped interface.
diff --git a/Documentation/hwmon/acpi_power_meter.rst b/Documentation/hwmon/acpi_power_meter.rst
index 4a0941ade0ca..8628c1161015 100644
--- a/Documentation/hwmon/acpi_power_meter.rst
+++ b/Documentation/hwmon/acpi_power_meter.rst
@@ -9,7 +9,7 @@ Supported systems:
 
     Prefix: 'power_meter'
 
-    Datasheet: http://acpi.info/, section 10.4.
+    Datasheet: https://uefi.org/specifications, section 10.4.
 
 Author: Darrick J. Wong
 
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index ce2730d61a8f..7540a5179a47 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -32,7 +32,7 @@ menuconfig ACPI
 	  Linux support for ACPI is based on Intel Corporation's ACPI
 	  Component Architecture (ACPI CA).  For more information on the
 	  ACPI CA, see:
-	  <http://acpica.org/>
+	  <https://acpica.org/>
 
 	  ACPI is an open industry specification originally co-developed by
 	  Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. Currently,
@@ -40,8 +40,7 @@ menuconfig ACPI
 	  the UEFI Forum and any UEFI member can join the ASWG and contribute
 	  to the ACPI specification.
 	  The specification is available at:
-	  <http://www.acpi.info>
-	  <http://www.uefi.org/acpi/specs>
+	  <https://uefi.org/specifications>
 
 if ACPI
 
@@ -99,23 +98,6 @@ config ACPI_SLEEP
 	depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
 	default y
 
-config ACPI_PROCFS_POWER
-	bool "Deprecated power /proc/acpi directories"
-	depends on X86 && PROC_FS
-	help
-	  For backwards compatibility, this option allows
-	  deprecated power /proc/acpi/ directories to exist, even when
-	  they have been replaced by functions in /sys.
-	  The deprecated directories (and their replacements) include:
-	  /proc/acpi/battery/* (/sys/class/power_supply/*) and
-	  /proc/acpi/ac_adapter/* (sys/class/power_supply/*).
-	  This option has no effect on /proc/acpi/ directories
-	  and functions which do not yet exist in /sys.
-	  This option, together with the proc directories, will be
-	  deleted in the future.
-
-	  Say N to delete power /proc/acpi/ directories that have moved to /sys.
-
 config ACPI_REV_OVERRIDE_POSSIBLE
 	bool "Allow supported ACPI revision to be overridden"
 	depends on X86
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index e81e1ebbfb32..9a957544e357 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -55,7 +55,6 @@ acpi-$(CONFIG_X86)		+= acpi_cmos_rtc.o
 acpi-$(CONFIG_X86)		+= x86/apple.o
 acpi-$(CONFIG_X86)		+= x86/utils.o
 acpi-$(CONFIG_DEBUG_FS)		+= debugfs.o
-acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
 acpi-y				+= acpi_lpat.o
 acpi-$(CONFIG_ACPI_LPIT)	+= acpi_lpit.o
 acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o
diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index 69d2db13886b..46a64e9fa716 100644
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -13,10 +13,6 @@
 #include <linux/types.h>
 #include <linux/dmi.h>
 #include <linux/delay.h>
-#ifdef CONFIG_ACPI_PROCFS_POWER
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#endif
 #include <linux/platform_device.h>
 #include <linux/power_supply.h>
 #include <linux/acpi.h>
@@ -66,12 +62,6 @@ static int acpi_ac_resume(struct device *dev);
 #endif
 static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
 
-#ifdef CONFIG_ACPI_PROCFS_POWER
-extern struct proc_dir_entry *acpi_lock_ac_dir(void);
-extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
-#endif
-
-
 static int ac_sleep_before_get_state_ms;
 static int ac_check_pmic = 1;
 
@@ -150,77 +140,6 @@ static enum power_supply_property ac_props[] = {
 	POWER_SUPPLY_PROP_ONLINE,
 };
 
-#ifdef CONFIG_ACPI_PROCFS_POWER
-/* --------------------------------------------------------------------------
-                              FS Interface (/proc)
-   -------------------------------------------------------------------------- */
-
-static struct proc_dir_entry *acpi_ac_dir;
-
-static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
-{
-	struct acpi_ac *ac = seq->private;
-
-
-	if (!ac)
-		return 0;
-
-	if (acpi_ac_get_state(ac)) {
-		seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
-		return 0;
-	}
-
-	seq_puts(seq, "state:                   ");
-	switch (ac->state) {
-	case ACPI_AC_STATUS_OFFLINE:
-		seq_puts(seq, "off-line\n");
-		break;
-	case ACPI_AC_STATUS_ONLINE:
-		seq_puts(seq, "on-line\n");
-		break;
-	default:
-		seq_puts(seq, "unknown\n");
-		break;
-	}
-
-	return 0;
-}
-
-static int acpi_ac_add_fs(struct acpi_ac *ac)
-{
-	struct proc_dir_entry *entry = NULL;
-
-	printk(KERN_WARNING PREFIX "Deprecated procfs I/F for AC is loaded,"
-			" please retry with CONFIG_ACPI_PROCFS_POWER cleared\n");
-	if (!acpi_device_dir(ac->device)) {
-		acpi_device_dir(ac->device) =
-			proc_mkdir(acpi_device_bid(ac->device), acpi_ac_dir);
-		if (!acpi_device_dir(ac->device))
-			return -ENODEV;
-	}
-
-	/* 'state' [R] */
-	entry = proc_create_single_data(ACPI_AC_FILE_STATE, S_IRUGO,
-			acpi_device_dir(ac->device), acpi_ac_seq_show, ac);
-	if (!entry)
-		return -ENODEV;
-	return 0;
-}
-
-static int acpi_ac_remove_fs(struct acpi_ac *ac)
-{
-
-	if (acpi_device_dir(ac->device)) {
-		remove_proc_entry(ACPI_AC_FILE_STATE,
-				  acpi_device_dir(ac->device));
-		remove_proc_entry(acpi_device_bid(ac->device), acpi_ac_dir);
-		acpi_device_dir(ac->device) = NULL;
-	}
-
-	return 0;
-}
-#endif
-
 /* --------------------------------------------------------------------------
                                    Driver Model
    -------------------------------------------------------------------------- */
@@ -236,7 +155,7 @@ static void acpi_ac_notify(struct acpi_device *device, u32 event)
 	default:
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "Unsupported event [0x%x]\n", event));
-	/* fall through */
+		fallthrough;
 	case ACPI_AC_NOTIFY_STATUS:
 	case ACPI_NOTIFY_BUS_CHECK:
 	case ACPI_NOTIFY_DEVICE_CHECK:
@@ -348,11 +267,6 @@ static int acpi_ac_add(struct acpi_device *device)
 	psy_cfg.drv_data = ac;
 
 	ac->charger_desc.name = acpi_device_bid(device);
-#ifdef CONFIG_ACPI_PROCFS_POWER
-	result = acpi_ac_add_fs(ac);
-	if (result)
-		goto end;
-#endif
 	ac->charger_desc.type = POWER_SUPPLY_TYPE_MAINS;
 	ac->charger_desc.properties = ac_props;
 	ac->charger_desc.num_properties = ARRAY_SIZE(ac_props);
@@ -372,9 +286,6 @@ static int acpi_ac_add(struct acpi_device *device)
 	register_acpi_notifier(&ac->battery_nb);
 end:
 	if (result) {
-#ifdef CONFIG_ACPI_PROCFS_POWER
-		acpi_ac_remove_fs(ac);
-#endif
 		kfree(ac);
 	}
 
@@ -418,10 +329,6 @@ static int acpi_ac_remove(struct acpi_device *device)
 	power_supply_unregister(ac->charger);
 	unregister_acpi_notifier(&ac->battery_nb);
 
-#ifdef CONFIG_ACPI_PROCFS_POWER
-	acpi_ac_remove_fs(ac);
-#endif
-
 	kfree(ac);
 
 	return 0;
@@ -447,18 +354,8 @@ static int __init acpi_ac_init(void)
 			}
 	}
 
-#ifdef CONFIG_ACPI_PROCFS_POWER
-	acpi_ac_dir = acpi_lock_ac_dir();
-	if (!acpi_ac_dir)
-		return -ENODEV;
-#endif
-
-
 	result = acpi_bus_register_driver(&acpi_ac_driver);
 	if (result < 0) {
-#ifdef CONFIG_ACPI_PROCFS_POWER
-		acpi_unlock_ac_dir(acpi_ac_dir);
-#endif
 		return -ENODEV;
 	}
 
@@ -468,9 +365,6 @@ static int __init acpi_ac_init(void)
 static void __exit acpi_ac_exit(void)
 {
 	acpi_bus_unregister_driver(&acpi_ac_driver);
-#ifdef CONFIG_ACPI_PROCFS_POWER
-	acpi_unlock_ac_dir(acpi_ac_dir);
-#endif
 }
 module_init(acpi_ac_init);
 module_exit(acpi_ac_exit);
diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c
index e7dc0133f817..6cc4c92d9ff9 100644
--- a/drivers/acpi/acpi_pad.c
+++ b/drivers/acpi/acpi_pad.c
@@ -88,7 +88,7 @@ static void round_robin_cpu(unsigned int tsk_index)
 	cpumask_var_t tmp;
 	int cpu;
 	unsigned long min_weight = -1;
-	unsigned long uninitialized_var(preferred_cpu);
+	unsigned long preferred_cpu;
 
 	if (!alloc_cpumask_var(&tmp, GFP_KERNEL))
 		return;
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 5379bc3f275d..b51ddf3bb616 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -79,7 +79,7 @@ static int acpi_processor_errata_piix4(struct pci_dev *dev)
 		 * PIIX4 models.
 		 */
 		errata.piix4.throttle = 1;
-		/* fall through*/
+		fallthrough;
 
 	case 2:		/* PIIX4E */
 	case 3:		/* PIIX4M */
diff --git a/drivers/acpi/acpica/evrgnini.c b/drivers/acpi/acpica/evrgnini.c
index aefc0145e583..89be3ccdad53 100644
--- a/drivers/acpi/acpica/evrgnini.c
+++ b/drivers/acpi/acpica/evrgnini.c
@@ -38,6 +38,7 @@ acpi_ev_system_memory_region_setup(acpi_handle handle,
 	union acpi_operand_object *region_desc =
 	    (union acpi_operand_object *)handle;
 	struct acpi_mem_space_context *local_region_context;
+	struct acpi_mem_mapping *mm;
 
 	ACPI_FUNCTION_TRACE(ev_system_memory_region_setup);
 
@@ -46,13 +47,14 @@ acpi_ev_system_memory_region_setup(acpi_handle handle,
 			local_region_context =
 			    (struct acpi_mem_space_context *)*region_context;
 
-			/* Delete a cached mapping if present */
+			/* Delete memory mappings if present */
 
-			if (local_region_context->mapped_length) {
-				acpi_os_unmap_memory(local_region_context->
-						     mapped_logical_address,
-						     local_region_context->
-						     mapped_length);
+			while (local_region_context->first_mm) {
+				mm = local_region_context->first_mm;
+				local_region_context->first_mm = mm->next_mm;
+				acpi_os_unmap_memory(mm->logical_address,
+						     mm->length);
+				ACPI_FREE(mm);
 			}
 			ACPI_FREE(local_region_context);
 			*region_context = NULL;
diff --git a/drivers/acpi/acpica/exprep.c b/drivers/acpi/acpica/exprep.c
index a4e306690a21..4a0f03157e08 100644
--- a/drivers/acpi/acpica/exprep.c
+++ b/drivers/acpi/acpica/exprep.c
@@ -473,10 +473,6 @@ acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
 				    (u8)access_byte_width;
 			}
 		}
-		/* An additional reference for the container */
-
-		acpi_ut_add_reference(obj_desc->field.region_obj);
-
 		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 				  "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
 				  obj_desc->field.start_field_bit_offset,
diff --git a/drivers/acpi/acpica/exregion.c b/drivers/acpi/acpica/exregion.c
index d15a66de26c0..4914dbc44517 100644
--- a/drivers/acpi/acpica/exregion.c
+++ b/drivers/acpi/acpica/exregion.c
@@ -41,6 +41,7 @@ acpi_ex_system_memory_space_handler(u32 function,
 	acpi_status status = AE_OK;
 	void *logical_addr_ptr = NULL;
 	struct acpi_mem_space_context *mem_info = region_context;
+	struct acpi_mem_mapping *mm = mem_info->cur_mm;
 	u32 length;
 	acpi_size map_length;
 	acpi_size page_boundary_map_length;
@@ -96,20 +97,37 @@ acpi_ex_system_memory_space_handler(u32 function,
 	 * Is 1) Address below the current mapping? OR
 	 *    2) Address beyond the current mapping?
 	 */
-	if ((address < mem_info->mapped_physical_address) ||
-	    (((u64) address + length) > ((u64)
-					 mem_info->mapped_physical_address +
-					 mem_info->mapped_length))) {
+	if (!mm || (address < mm->physical_address) ||
+	    ((u64) address + length > (u64) mm->physical_address + mm->length)) {
 		/*
-		 * The request cannot be resolved by the current memory mapping;
-		 * Delete the existing mapping and create a new one.
+		 * The request cannot be resolved by the current memory mapping.
+		 *
+		 * Look for an existing saved mapping covering the address range
+		 * at hand.  If found, save it as the current one and carry out
+		 * the access.
 		 */
-		if (mem_info->mapped_length) {
+		for (mm = mem_info->first_mm; mm; mm = mm->next_mm) {
+			if (mm == mem_info->cur_mm)
+				continue;
+
+			if (address < mm->physical_address)
+				continue;
 
-			/* Valid mapping, delete it */
+			if ((u64) address + length >
+					(u64) mm->physical_address + mm->length)
+				continue;
 
-			acpi_os_unmap_memory(mem_info->mapped_logical_address,
-					     mem_info->mapped_length);
+			mem_info->cur_mm = mm;
+			goto access;
+		}
+
+		/* Create a new mappings list entry */
+		mm = ACPI_ALLOCATE_ZEROED(sizeof(*mm));
+		if (!mm) {
+			ACPI_ERROR((AE_INFO,
+				    "Unable to save memory mapping at 0x%8.8X%8.8X, size %u",
+				    ACPI_FORMAT_UINT64(address), length));
+			return_ACPI_STATUS(AE_NO_MEMORY);
 		}
 
 		/*
@@ -143,29 +161,39 @@ acpi_ex_system_memory_space_handler(u32 function,
 
 		/* Create a new mapping starting at the address given */
 
-		mem_info->mapped_logical_address =
-		    acpi_os_map_memory(address, map_length);
-		if (!mem_info->mapped_logical_address) {
+		logical_addr_ptr = acpi_os_map_memory(address, map_length);
+		if (!logical_addr_ptr) {
 			ACPI_ERROR((AE_INFO,
 				    "Could not map memory at 0x%8.8X%8.8X, size %u",
 				    ACPI_FORMAT_UINT64(address),
 				    (u32)map_length));
-			mem_info->mapped_length = 0;
+			ACPI_FREE(mm);
 			return_ACPI_STATUS(AE_NO_MEMORY);
 		}
 
 		/* Save the physical address and mapping size */
 
-		mem_info->mapped_physical_address = address;
-		mem_info->mapped_length = map_length;
+		mm->logical_address = logical_addr_ptr;
+		mm->physical_address = address;
+		mm->length = map_length;
+
+		/*
+		 * Add the new entry to the mappigs list and save it as the
+		 * current mapping.
+		 */
+		mm->next_mm = mem_info->first_mm;
+		mem_info->first_mm = mm;
+
+		mem_info->cur_mm = mm;
 	}
 
+access:
 	/*
 	 * Generate a logical pointer corresponding to the address we want to
 	 * access
 	 */
-	logical_addr_ptr = mem_info->mapped_logical_address +
-	    ((u64) address - (u64) mem_info->mapped_physical_address);
+	logical_addr_ptr = mm->logical_address +
+		((u64) address - (u64) mm->physical_address);
 
 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 			  "System-Memory (width %u) R/W %u Address=%8.8X%8.8X\n",
diff --git a/drivers/acpi/acpica/utdelete.c b/drivers/acpi/acpica/utdelete.c
index c365faf4e6cd..4c0d4e434196 100644
--- a/drivers/acpi/acpica/utdelete.c
+++ b/drivers/acpi/acpica/utdelete.c
@@ -568,11 +568,6 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 			next_object = object->buffer_field.buffer_obj;
 			break;
 
-		case ACPI_TYPE_LOCAL_REGION_FIELD:
-
-			next_object = object->field.region_obj;
-			break;
-
 		case ACPI_TYPE_LOCAL_BANK_FIELD:
 
 			next_object = object->bank_field.bank_obj;
@@ -613,6 +608,7 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 			}
 			break;
 
+		case ACPI_TYPE_LOCAL_REGION_FIELD:
 		case ACPI_TYPE_REGION:
 		default:
 
diff --git a/drivers/acpi/acpica/utids.c b/drivers/acpi/acpica/utids.c
index 3bb06935a2ad..3e68864ef242 100644
--- a/drivers/acpi/acpica/utids.c
+++ b/drivers/acpi/acpica/utids.c
@@ -263,8 +263,7 @@ acpi_ut_execute_CID(struct acpi_namespace_node *device_node,
 	 * 3) Size of the actual CID strings
 	 */
 	cid_list_size = sizeof(struct acpi_pnp_device_id_list) +
-	    ((count - 1) * sizeof(struct acpi_pnp_device_id)) +
-	    string_area_size;
+	    (count * sizeof(struct acpi_pnp_device_id)) + string_area_size;
 
 	cid_list = ACPI_ALLOCATE_ZEROED(cid_list_size);
 	if (!cid_list) {
diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
index 953a2fae8b15..6e980fe16772 100644
--- a/drivers/acpi/apei/hest.c
+++ b/drivers/acpi/apei/hest.c
@@ -227,7 +227,7 @@ __setup("hest_disable", setup_hest_disable);
 void __init acpi_hest_init(void)
 {
 	acpi_status status;
-	int rc = -ENODEV;
+	int rc;
 	unsigned int ghes_count = 0;
 
 	if (hest_disable) {
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 366c389175d8..cab4af532f36 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -24,12 +24,6 @@
 
 #include <asm/unaligned.h>
 
-#ifdef CONFIG_ACPI_PROCFS_POWER
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <linux/uaccess.h>
-#endif
-
 #include <linux/acpi.h>
 #include <linux/power_supply.h>
 
@@ -69,11 +63,6 @@ static unsigned int cache_time = 1000;
 module_param(cache_time, uint, 0644);
 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
 
-#ifdef CONFIG_ACPI_PROCFS_POWER
-extern struct proc_dir_entry *acpi_lock_battery_dir(void);
-extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
-#endif
-
 static const struct acpi_device_id battery_device_ids[] = {
 	{"PNP0C0A", 0},
 	{"", 0},
@@ -1024,226 +1013,6 @@ static void acpi_battery_refresh(struct acpi_battery *battery)
 }
 
 /* --------------------------------------------------------------------------
-                              FS Interface (/proc)
-   -------------------------------------------------------------------------- */
-
-#ifdef CONFIG_ACPI_PROCFS_POWER
-static struct proc_dir_entry *acpi_battery_dir;
-
-static const char *acpi_battery_units(const struct acpi_battery *battery)
-{
-	return