Merge branches 'acpi-numa', 'acpi-tables' and 'acpi-osi'

* acpi-numa:
  ACPI / SRAT: fix SRAT parsing order with both LAPIC and X2APIC present

* acpi-tables:
  ACPI / tables: Fix DSDT override mechanism
  ACPI / tables: Convert initrd table override to table upgrade mechanism
  ACPI / x86: Cleanup initrd related code
  ACPI / tables: Move table override mechanisms to tables.c

* acpi-osi:
  ACPI / osi: Collect _OSI handling into one single file
  ACPI / osi: Cleanup coding style issues before creating a separate OSI source file
  ACPI / osi: Cleanup OSI handling code to use bool
  ACPI / osi: Fix default _OSI(Darwin) support
  ACPI / osi: Add acpi_osi=!! to allow reverting acpi_osi=!
  ACPI / osi: Cleanup _OSI("Linux") related code before introducing new support
  ACPI / osi: Fix an issue that acpi_osi=!* cannot disable ACPICA internal strings

Conflicts:
	drivers/acpi/internal.h

Documentation/acpi/initrd_table_override.txt

-Overriding ACPI tables via initrd
-=================================
+Upgrading ACPI tables via initrd
+================================
 
 1) Introduction (What is this about)
 2) What is this for
@@ -9,12 +9,14 @@ Overriding ACPI tables via initrd
 1) What is this about
 ---------------------
 
-If the ACPI_INITRD_TABLE_OVERRIDE compile option is true, it is possible to
-override nearly any ACPI table provided by the BIOS with an instrumented,
-modified one.
+If the ACPI_TABLE_UPGRADE compile option is true, it is possible to
+upgrade the ACPI execution environment that is defined by the ACPI tables
+via upgrading the ACPI tables provided by the BIOS with an instrumented,
+modified, more recent version one, or installing brand new ACPI tables.
 
-For a full list of ACPI tables that can be overridden, take a look at
-the char *table_sigs[MAX_ACPI_SIGNATURE]; definition in drivers/acpi/osl.c
+For a full list of ACPI tables that can be upgraded/installed, take a look
+at the char *table_sigs[MAX_ACPI_SIGNATURE]; definition in
+drivers/acpi/tables.c.
 All ACPI tables iasl (Intel's ACPI compiler and disassembler) knows should
 be overridable, except:
    - ACPI_SIG_RSDP (has a signature of 6 bytes)
@@ -25,17 +27,20 @@ Both could get implemented as well.
 2) What is this for
 -------------------
 
-Please keep in mind that this is a debug option.
-ACPI tables should not get overridden for productive use.
-If BIOS ACPI tables are overridden the kernel will get tainted with the
-TAINT_OVERRIDDEN_ACPI_TABLE flag.
-Complain to your platform/BIOS vendor if you find a bug which is so sever
-that a workaround is not accepted in the Linux kernel.
+Complain to your platform/BIOS vendor if you find a bug which is so severe
+that a workaround is not accepted in the Linux kernel. And this facility
+allows you to upgrade the buggy tables before your platform/BIOS vendor
+releases an upgraded BIOS binary.
 
-Still, it can and should be enabled in any kernel, because:
-  - There is no functional change with not instrumented initrds
-  - It provides a powerful feature to easily debug and test ACPI BIOS table
-    compatibility with the Linux kernel.
+This facility can be used by platform/BIOS vendors to provide a Linux
+compatible environment without modifying the underlying platform firmware.
+
+This facility also provides a powerful feature to easily debug and test
+ACPI BIOS table compatibility with the Linux kernel by modifying old
+platform provided ACPI tables or inserting new ACPI tables.
+
+It can and should be enabled in any kernel because there is no functional
+change with not instrumented initrds.
 
 
 3) How does it work
@@ -50,23 +55,31 @@ iasl -d *.dat
 # For example add this statement into a _PRT (PCI Routing Table) function
 # of the DSDT:
 Store("HELLO WORLD", debug)
+# And increase the OEM Revision. For example, before modification:
+DefinitionBlock ("DSDT.aml", "DSDT", 2, "INTEL ", "TEMPLATE", 0x00000000)
+# After modification:
+DefinitionBlock ("DSDT.aml", "DSDT", 2, "INTEL ", "TEMPLATE", 0x00000001)
 iasl -sa dsdt.dsl
 # Add the raw ACPI tables to an uncompressed cpio archive.
-# They must be put into a /kernel/firmware/acpi directory inside the
-# cpio archive.
-# The uncompressed cpio archive must be the first.
-# Other, typically compressed cpio archives, must be
-# concatenated on top of the uncompressed one.
+# They must be put into a /kernel/firmware/acpi directory inside the cpio
+# archive. Note that if the table put here matches a platform table
+# (similar Table Signature, and similar OEMID, and similar OEM Table ID)
+# with a more recent OEM Revision, the platform table will be upgraded by
+# this table. If the table put here doesn't match a platform table
+# (dissimilar Table Signature, or dissimilar OEMID, or dissimilar OEM Table
+# ID), this table will be appended.
 mkdir -p kernel/firmware/acpi
 cp dsdt.aml kernel/firmware/acpi
-# A maximum of: #define ACPI_OVERRIDE_TABLES 10
-# tables are  currently allowed (see osl.c):
+# A maximum of "NR_ACPI_INITRD_TABLES (64)" tables are currently allowed
+# (see osl.c):
 iasl -sa facp.dsl
 iasl -sa ssdt1.dsl
 cp facp.aml kernel/firmware/acpi
 cp ssdt1.aml kernel/firmware/acpi
-# Create the uncompressed cpio archive and concatenate the original initrd
-# on top:
+# The uncompressed cpio archive must be the first. Other, typically
+# compressed cpio archives, must be concatenated on top of the uncompressed
+# one. Following command creates the uncompressed cpio archive and
+# concatenates the original initrd on top:
 find kernel | cpio -H newc --create > /boot/instrumented_initrd
 cat /boot/initrd >>/boot/instrumented_initrd
 # reboot with increased acpi debug level, e.g. boot params:

Documentation/kernel-parameters.txt

@@ -312,6 +312,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			acpi_osi=!*		# remove all strings
 			acpi_osi=!		# disable all built-in OS vendor
 						  strings
+			acpi_osi=!!		# enable all built-in OS vendor
+						  strings
 			acpi_osi=		# disable all strings
 
 			'acpi_osi=!' can be used in combination with single or

arch/x86/kernel/setup.c

@@ -398,6 +398,11 @@ static void __init reserve_initrd(void)
 
 	memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
 }
+
+static void __init early_initrd_acpi_init(void)
+{
+	early_acpi_table_init((void *)initrd_start, initrd_end - initrd_start);
+}
 #else
 static void __init early_reserve_initrd(void)
 {
@@ -405,6 +410,9 @@ static void __init early_reserve_initrd(void)
 static void __init reserve_initrd(void)
 {
 }
+static void __init early_initrd_acpi_init(void)
+{
+}
 #endif /* CONFIG_BLK_DEV_INITRD */
 
 static void __init parse_setup_data(void)
@@ -1138,9 +1146,7 @@ void __init setup_arch(char **cmdline_p)
 
 	reserve_initrd();
 
-#if defined(CONFIG_ACPI) && defined(CONFIG_BLK_DEV_INITRD)
-	acpi_initrd_override((void *)initrd_start, initrd_end - initrd_start);
-#endif
+	early_initrd_acpi_init();
 
 	vsmp_init();
 

drivers/acpi/Kconfig

@@ -311,12 +311,12 @@ config ACPI_CUSTOM_DSDT
 	bool
 	default ACPI_CUSTOM_DSDT_FILE != ""
 
-config ACPI_INITRD_TABLE_OVERRIDE
-	bool "ACPI tables override via initrd"
+config ACPI_TABLE_UPGRADE
+	bool "Allow upgrading ACPI tables via initrd"
 	depends on BLK_DEV_INITRD && X86
-	default n
+	default y
 	help
-	  This option provides functionality to override arbitrary ACPI tables
+	  This option provides functionality to upgrade arbitrary ACPI tables
 	  via initrd. No functional change if no ACPI tables are passed via
 	  initrd, therefore it's safe to say Y.
 	  See Documentation/acpi/initrd_table_override.txt for details

drivers/acpi/Makefile

@@ -18,7 +18,7 @@ obj-$(CONFIG_ACPI)		+= acpi.o \
 					acpica/
 
 # All the builtin files are in the "acpi." module_param namespace.
-acpi-y				+= osl.o utils.o reboot.o
+acpi-y				+= osi.o osl.o utils.o reboot.o
 acpi-y				+= nvs.o
 
 # Power management related files

drivers/acpi/blacklist.c

@@ -3,7 +3,7 @@
  *
  *  Check to see if the given machine has a known bad ACPI BIOS
  *  or if the BIOS is too old.
- *  Check given machine against acpi_osi_dmi_table[].
+ *  Check given machine against acpi_rev_dmi_table[].
  *
  *  Copyright (C) 2004 Len Brown <len.brown@intel.com>
  *  Copyright (C) 2002 Andy Grover <andrew.grover@intel.com>
@@ -47,7 +47,7 @@ struct acpi_blacklist_item {
 	u32 is_critical_error;
 };
 
-static struct dmi_system_id acpi_osi_dmi_table[] __initdata;
+static struct dmi_system_id acpi_rev_dmi_table[] __initdata;
 
 /*
  * POLICY: If *anything* doesn't work, put it on the blacklist.
@@ -128,36 +128,12 @@ int __init acpi_blacklisted(void)
 		}
 	}
 
-	dmi_check_system(acpi_osi_dmi_table);
+	(void)early_acpi_osi_init();
+	dmi_check_system(acpi_rev_dmi_table);
 
 	return blacklisted;
 }
 #ifdef CONFIG_DMI
-static int __init dmi_enable_osi_linux(const struct dmi_system_id *d)
-{
-	acpi_dmi_osi_linux(1, d);	/* enable */
-	return 0;
-}
-static int __init dmi_disable_osi_vista(const struct dmi_system_id *d)
-{
-	printk(KERN_NOTICE PREFIX "DMI detected: %s\n", d->ident);
-	acpi_osi_setup("!Windows 2006");
-	acpi_osi_setup("!Windows 2006 SP1");
-	acpi_osi_setup("!Windows 2006 SP2");
-	return 0;
-}
-static int __init dmi_disable_osi_win7(const struct dmi_system_id *d)
-{
-	printk(KERN_NOTICE PREFIX "DMI detected: %s\n", d->ident);
-	acpi_osi_setup("!Windows 2009");
-	return 0;
-}
-static int __init dmi_disable_osi_win8(const struct dmi_system_id *d)
-{
-	printk(KERN_NOTICE PREFIX "DMI detected: %s\n", d->ident);
-	acpi_osi_setup("!Windows 2012");
-	return 0;
-}
 #ifdef CONFIG_ACPI_REV_OVERRIDE_POSSIBLE
 static int __init dmi_enable_rev_override(const struct dmi_system_id *d)
 {
@@ -168,169 +144,7 @@ static int __init dmi_enable_rev_override(const struct dmi_system_id *d)
 }
 #endif
 
-static struct dmi_system_id acpi_osi_dmi_table[] __initdata = {
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "Fujitsu Siemens",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile V5505"),
-		},
-	},
-	{
-	/*
-	 * There have a NVIF method in MSI GX723 DSDT need call by Nvidia
-	 * driver (e.g. nouveau) when user press brightness hotkey.
-	 * Currently, nouveau driver didn't do the job and it causes there
-	 * have a infinite while loop in DSDT when user press hotkey.
-	 * We add MSI GX723's dmi information to this table for workaround
-	 * this issue.
-	 * Will remove MSI GX723 from the table after nouveau grows support.
-	 */
-	.callback = dmi_disable_osi_vista,
-	.ident = "MSI GX723",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star International"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "GX723"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "Sony VGN-NS10J_S",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NS10J_S"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "Sony VGN-SR290J",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR290J"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "VGN-NS50B_L",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NS50B_L"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "VGN-SR19XN",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR19XN"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "Toshiba Satellite L355",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
-		     DMI_MATCH(DMI_PRODUCT_VERSION, "Satellite L355"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win7,
-	.ident = "ASUS K50IJ",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "K50IJ"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "Toshiba P305D",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "Satellite P305D"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_vista,
-	.ident = "Toshiba NB100",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "NB100"),
-		},
-	},
-
-	/*
-	 * The wireless hotkey does not work on those machines when
-	 * returning true for _OSI("Windows 2012")
-	 */
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Inspiron 7737",
-	.matches = {
-		    DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		    DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7737"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Inspiron 7537",
-	.matches = {
-		    DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		    DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7537"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Inspiron 5437",
-	.matches = {
-		    DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		    DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 5437"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Inspiron 3437",
-	.matches = {
-		    DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		    DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 3437"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Vostro 3446",
-	.matches = {
-		    DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		    DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3446"),
-		},
-	},
-	{
-	.callback = dmi_disable_osi_win8,
-	.ident = "Dell Vostro 3546",
-	.matches = {
-		    DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
-		    DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3546"),
-		},
-	},
-
-	/*
-	 * BIOS invocation of _OSI(Linux) is almost always a BIOS bug.
-	 * Linux ignores it, except for the machines enumerated below.
-	 */
-
-	/*
-	 * Without this this EEEpc exports a non working WMI interface, with
-	 * this it exports a working "good old" eeepc_laptop interface, fixing
-	 * both brightness control, and rfkill not working.
-	 */
-	{
-	.callback = dmi_enable_osi_linux,
-	.ident = "Asus EEE PC 1015PX",
-	.matches = {
-		     DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer INC."),
-		     DMI_MATCH(DMI_PRODUCT_NAME, "1015PX"),
-		},
-	},
-
+static struct dmi_system_id acpi_rev_dmi_table[] __initdata = {
 #ifdef CONFIG_ACPI_REV_OVERRIDE_POSSIBLE
 	/*
 	 * DELL XPS 13 (2015) switches sound between HDA and I2S

drivers/acpi/internal.h

@@ -20,7 +20,8 @@
 
 #define PREFIX "ACPI: "
 
-void acpi_initrd_initialize_tables(void);
+int early_acpi_osi_init(void);
+int acpi_osi_init(void);
 acpi_status acpi_os_initialize1(void);
 void init_acpi_device_notify(void);
 int acpi_scan_init(void);

drivers/acpi/numa.c

@@ -327,10 +327,18 @@ int __init acpi_numa_init(void)
 
 	/* SRAT: Static Resource Affinity Table */
 	if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) {
-		acpi_table_parse_srat(ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY,
-				     acpi_parse_x2apic_affinity, 0);
-		acpi_table_parse_srat(ACPI_SRAT_TYPE_CPU_AFFINITY,
-				     acpi_parse_processor_affinity, 0);
+		struct acpi_subtable_proc srat_proc[2];
+
+		memset(srat_proc, 0, sizeof(srat_proc));
+		srat_proc[0].id = ACPI_SRAT_TYPE_CPU_AFFINITY;
+		srat_proc[0].handler = acpi_parse_processor_affinity;
+		srat_proc[1].id = ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY;
+		srat_proc[1].handler = acpi_parse_x2apic_affinity;
+
+		acpi_table_parse_entries_array(ACPI_SIG_SRAT,
+					sizeof(struct acpi_table_srat),
+					srat_proc, ARRAY_SIZE(srat_proc), 0);
+
 		cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY,
 					    acpi_parse_memory_affinity,
 					    NR_NODE_MEMBLKS);

drivers/acpi/tables.c

@@ -32,8 +32,14 @@
 #include <linux/errno.h>
 #include <linux/acpi.h>
 #include <linux/bootmem.h>
+#include <linux/earlycpio.h>
+#include <linux/memblock.h>
 #include "internal.h"
 
+#ifdef CONFIG_ACPI_CUSTOM_DSDT
+#include CONFIG_ACPI_CUSTOM_DSDT_FILE
+#endif
+
 #define ACPI_MAX_TABLES		128
 
 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
@@ -433,6 +439,314 @@ static void __init check_multiple_madt(void)
 	return;
 }
 
+static void acpi_table_taint(struct acpi_table_header *table)
+{
+	pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
+		table->signature, table->oem_table_id);
+	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
+}
+
+#ifdef CONFIG_ACPI_TABLE_UPGRADE
+static u64 acpi_tables_addr;
+static int all_tables_size;
+
+/* Copied from acpica/tbutils.c:acpi_tb_checksum() */
+static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
+{
+	u8 sum = 0;
+	u8 *end = buffer + length;
+
+	while (buffer < end)
+		sum = (u8) (sum + *(buffer++));
+	return sum;
+}
+
+/* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
+static const char * const table_sigs[] = {
+	ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
+	ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
+	ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
+	ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
+	ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
+	ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
+	ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
+	ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
+	ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, NULL };
+
+#define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
+
+#define NR_ACPI_INITRD_TABLES 64
+static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
+static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
+
+#define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
+
+static void __init acpi_table_initrd_init(void *data, size_t size)
+{
+	int sig, no, table_nr = 0, total_offset = 0;
+	long offset = 0;
+	struct acpi_table_header *table;
+	char cpio_path[32] = "kernel/firmware/acpi/";
+	struct cpio_data file;
+
+	if (data == NULL || size == 0)
+		return;
+
+	for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
+		file = find_cpio_data(cpio_path, data, size, &offset);
+		if (!file.data)
+			break;
+
+		data += offset;
+		size -= offset;
+
+		if (file.size < sizeof(struct acpi_table_header)) {
+			pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
+				cpio_path, file.name);
+			continue;
+		}
+
+		table = file.data;
+
+		for (sig = 0; table_sigs[sig]; sig++)
+			if (!memcmp(table->signature, table_sigs[sig], 4))
+				break;
+
+		if (!table_sigs[sig]) {
+			pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
+				cpio_path, file.name);
+			continue;
+		}
+		if (file.size != table->length) {
+			pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
+				cpio_path, file.name);
+			continue;
+		}
+		if (acpi_table_checksum(file.data, table->length)) {
+			pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
+				cpio_path, file.name);
+			continue;
+		}
+
+		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
+			table->signature, cpio_path, file.name, table->length);
+
+		all_tables_size += table->length;
+		acpi_initrd_files[table_nr].data = file.data;
+		acpi_initrd_files[table_nr].size = file.size;
+		table_nr++;
+	}
+	if (table_nr == 0)
+		return;
+
+	acpi_tables_addr =
+		memblock_find_in_range(0, max_low_pfn_mapped << PAGE_SHIFT,
+				       all_tables_size, PAGE_SIZE);
+	if (!acpi_tables_addr) {
+		WARN_ON(1);
+		return;
+	}
+	/*
+	 * Only calling e820_add_reserve does not work and the
+	 * tables are invalid (memory got used) later.
+	 * memblock_reserve works as expected and the tables won't get modified.
+	 * But it's not enough on X86 because ioremap will
+	 * complain later (used by acpi_os_map_memory) that the pages
+	 * that should get mapped are not marked "reserved".
+	 * Both memblock_reserve and e820_add_region (via arch_reserve_mem_area)
+	 * works fine.
+	 */
+	memblock_reserve(acpi_tables_addr, all_tables_size);
+	arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
+
+	/*
+	 * early_ioremap only can remap 256k one time. If we map all
+	 * tables one time, we will hit the limit. Need to map chunks
+	 * one by one during copying the same as that in relocate_initrd().
+	 */
+	for (no = 0; no < table_nr; no++) {
+		unsigned char *src_p = acpi_initrd_files[no].data;
+		phys_addr_t size = acpi_initrd_files[no].size;
+		phys_addr_t dest_addr = acpi_tables_addr + total_offset;
+		phys_addr_t slop, clen;
+		char *dest_p;
+
+		total_offset += size;
+
+		while (size) {
+			slop = dest_addr & ~PAGE_MASK;
+			clen = size;
+			if (clen > MAP_CHUNK_SIZE - slop)
+				clen = MAP_CHUNK_SIZE - slop;
+			dest_p = early_ioremap(dest_addr & PAGE_MASK,
+						 clen + slop);
+			memcpy(dest_p + slop, src_p, clen);
+			early_iounmap(dest_p, clen + slop);
+			src_p += clen;
+			dest_addr += clen;
+			size -= clen;
+		}
+	}
+}
+
+static acpi_status
+acpi_table_initrd_override(struct acpi_table_header *existing_table,
+			   acpi_physical_address *address, u32 *length)
+{
+	int table_offset = 0;
+	int table_index = 0;
+	struct acpi_table_header *table;
+	u32 table_length;
+
+	*length = 0;
+	*address = 0;
+	if (!acpi_tables_addr)
+		return AE_OK;
+
+	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
+		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
+					   ACPI_HEADER_SIZE);
+		if (table_offset + table->length > all_tables_size) {
+			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+			WARN_ON(1);
+			return AE_OK;
+		}
+
+		table_length = table->length;
+
+		/* Only override tables matched */
+		if (memcmp(existing_table->signature, table->signature, 4) ||
+		    memcmp(table->oem_id, existing_table->oem_id,
+			   ACPI_OEM_ID_SIZE) ||
+		    memcmp(table->oem_table_id, existing_table->oem_table_id,
+			   ACPI_OEM_TABLE_ID_SIZE)) {
+			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+			goto next_table;
+		}
+		/*
+		 * Mark the table to avoid being used in
+		 * acpi_table_initrd_scan() and check the revision.
+		 */
+		if (test_and_set_bit(table_index, acpi_initrd_installed) ||
+		    existing_table->oem_revision >= table->oem_revision) {
+			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+			goto next_table;
+		}
+
+		*length = table_length;
+		*address = acpi_tables_addr + table_offset;
+		pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
+			table->signature, table->oem_id,
+			table->oem_table_id);
+		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+		break;
+
+next_table:
+		table_offset += table_length;
+		table_index++;
+	}
+	return AE_OK;
+}
+
+static void __init acpi_table_initrd_scan(void)
+{
+	int table_offset = 0;
+	int table_index = 0;
+	u32 table_length;
+	struct acpi_table_header *table;
+
+	if (!acpi_tables_addr)
+		return;
+
+	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
+		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
+					   ACPI_HEADER_SIZE);
+		if (table_offset + table->length > all_tables_size) {
+			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+			WARN_ON(1);
+			return;
+		}
+
+		table_length = table->length;
+
+		/* Skip RSDT/XSDT which should only be used for override */
+		if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) ||
+		    ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) {
+			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+			goto next_table;
+		}
+		/*
+		 * Mark the table to avoid being used in
+		 * acpi_table_initrd_override(). Though this is not possible
+		 * because override is disabled in acpi_install_table().
+		 */
+		if (test_and_set_bit(table_index, acpi_initrd_installed)) {
+			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+			goto next_table;
+		}
+
+		pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
+			table->signature, table->oem_id,
+			table->oem_table_id);
+		acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+		acpi_install_table(acpi_tables_addr + table_offset, TRUE);
+next_table:
+		table_offset += table_length;
+		table_index++;
+	}
+}
+#else
+static void __init acpi_table_initrd_init(void *data, size_t size)
+{
+}
+
+static acpi_status
+acpi_table_initrd_override(struct acpi_table_header *existing_table,
+			   acpi_physical_address *address,
+			   u32 *table_length)
+{
+	*table_length = 0;
+	*address = 0;
+	return AE_OK;
+}
+
+static void __init acpi_table_initrd_scan(void)
+{
+}
+#endif /* CONFIG_ACPI_TABLE_UPGRADE */
+
+acpi_status
+acpi_os_physical_table_override(struct acpi_table_header *existing_table,
+				acpi_physical_address *address,
+				u32 *table_length)
+{
+	return acpi_table_initrd_override(existing_table, address,
+					  table_length);
+}
+
+acpi_status
+acpi_os_table_override(struct acpi_table_header *existing_table,
+		       struct acpi_table_header **new_table)
+{
+	if (!existing_table || !new_table)
+		return AE_BAD_PARAMETER;
+
+	*new_table = NULL;
+
+#ifdef CONFIG_ACPI_CUSTOM_DSDT
+	if (strncmp(existing_table->signature, "DSDT", 4) == 0)
+		*new_table = (struct acpi_table_header *)AmlCode;
+#endif
+	if (*new_table != NULL)
+		acpi_table_taint(existing_table);
+	return AE_OK;
+}
+
+void __init early_acpi_table_init(void *data, size_t size)
+{
+	acpi_table_initrd_init(data, size);
+}
+
 /*
  * acpi_table_init()
  *
@@ -457,7 +771,7 @@ int __init acpi_table_init(void)
 	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
 	if (ACPI_FAILURE(status))
 		return -EINVAL;
-	acpi_initrd_initialize_tables();
+	acpi_table_initrd_scan();
 
 	check_multiple_madt();
 	return 0;

include/linux/acpi.h

@@ -190,14 +190,6 @@ static inline int acpi_debugger_notify_command_complete(void)
 }
 #endif
 
-#ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
-void acpi_initrd_override(void *data, size_t size);
-#else
-static inline void acpi_initrd_override(void *data, size_t size)
-{
-}
-#endif
-
 #define BAD_MADT_ENTRY(entry, end) (					    \
 		(!entry) || (unsigned long)entry + sizeof(*entry) > end ||  \
 		((struct acpi_subtable_header *)entry)->length < sizeof(*entry))
@@ -216,6 +208,7 @@ void acpi_boot_table_init (void);
 int acpi_mps_check (void);
 int acpi_numa_init (void);
 
+void early_acpi_table_init(void *data, size_t size);
 int acpi_table_init (void);
 int acpi_table_parse(char *id, acpi_tbl_table_handler handler);
 int __init acpi_parse_entries(char *id, unsigned long table_size,
@@ -360,7 +353,6 @@ extern bool wmi_has_guid(const char *guid);
 extern char acpi_video_backlight_string[];
 extern long acpi_is_video_device(acpi_handle handle);
 extern int acpi_blacklisted(void);
-extern void acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d);
 extern void acpi_osi_setup(char *str);
 extern bool acpi_osi_is_win8(void);
 
@@ -597,6 +589,7 @@ static inline const char *acpi_dev_name(struct acpi_device *adev)
 	return NULL;
 }
 
+static inline void early_acpi_table_init(void *data, size_t size) { }
 static inline void acpi_early_init(void) { }
 static inline void acpi_subsystem_init(void) { }