FAILED: patch "[PATCH] ACPICA / Interpreter: Fix a regression triggered because of ACPICA: Events: Enhance acpi_ev_execute_reg_method() to" failed to apply to 4.5-stable tree

From 5508df89756f8378024828e185724a9bd2348985 Mon Sep 17 00:00:00 2001

From: [email protected] [mailto:[email protected]]
Subject: FAILED: patch "[PATCH] ACPICA / Interpreter: Fix a regression triggered because of ACPICA: Events: Enhance acpi_ev_execute_reg_method() to" failed to apply to 4.5-stable tree

The patch below does not apply to the 4.5-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5508df89756f8378024828e185724a9bd2348985 Mon Sep 17 00:00:00 2001
From: Lv Zheng <[email protected]>
Date: Thu, 10 Mar 2016 10:54:29 +0800
Subject: [PATCH] ACPICA / Interpreter: Fix a regression triggered because of
wrong Linux ECDT support

It is reported that the following commit triggers regressions:
Linux commit: efaed9be998b5ae0afb7458e057e5f4402b43fa0 ACPICA commit: 31178590dde82368fdb0f6b0e466b6c0add96c57
Subject: ACPICA: Events: Enhance acpi_ev_execute_reg_method() to
ensure no _REG evaluations can happen during OS early boot stages

This is because that the ECDT support is not corrected in Linux, and Linux requires to execute _REG for ECDT (though this sounds so wrong), we need to ensure acpi_gbl_namespace_initialized is set before ECDT probing in order for _REG to be executed. Since we have to move "acpi_gbl_namespace_initialized = TRUE" to the initialization step happening before ECDT probing, acpi_load_tables() is the best candidate for now. Thus this patch fixes the regression by doing so.

But if the ECDT support is fixed, Linux will not execute _REG for ECDT, and ECDT probing will happen before acpi_load_tables(). At that time, we still want to ensure acpi_gbl_namespace_initialized is set after executing acpi_ns_initialize_objects() (under the condition of acpi_gbl_group_module_level_code = FALSE), this patch also moves acpi_ns_initialize_objects() to acpi_load_tables() accordingly.

Since acpi_ns_initialize_objects() doesn't seem to be skippable, this patch also removes ACPI_NO_OBJECT_INIT for the one invoked in acpi_load_tables(). And since the default region handlers should always be installed before loading the tables, this patch also removes useless acpi_gbl_group_module_level_code check accordingly. Reported by Chris Bainbridge, Fixed by Lv Zheng.

Fixes efaed9be998b (ACPICA: Events: Enhance acpi_ev_execute_reg_method()

to ensure no _REG evaluations can happen during OS early boot stages)

Reported-and-tested-by Chris Bainbridge <[email protected]>

Signed-off-by Lv Zheng <[email protected]>

Signed-off-by Rafael J. Wysocki <[email protected]>

drivers/acpi/acpica/nsinit.c +2 -0

index f029a3da67eb..d4aa8b696ee9 100644
@@ -84,6 +84,8 @@ acpi_status acpi_ns_initialize_objects(void)
 
 	ACPI_FUNCTION_TRACE(ns_initialize_objects);
 
+	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
+			  "[Init] Completing Initialization of ACPI Objects\n"));
 	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
 			  "**** Starting initialization of namespace objects
 ****\n"));

drivers/acpi/acpica/nsinit.c +0 -0

 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,

drivers/acpi/acpica/tbxfload.c +19 -7

index 9496b84476a4..3151968c10d1 100644
@@ -81,13 +81,11 @@ acpi_status __init acpi_load_tables(void)
 	 * between acpi_initialize_subsystem() and acpi_load_tables() to use
 	 * their customized default region handlers.
 	 */
-	if (acpi_gbl_group_module_level_code) {
-		status = acpi_ev_install_region_handlers();
-		if (ACPI_FAILURE(status) && status != AE_ALREADY_EXISTS) {
-			ACPI_EXCEPTION((AE_INFO, status,
-					"During Region initialization"));
-			return_ACPI_STATUS(status);
-		}
+	status = acpi_ev_install_region_handlers();
+	if (ACPI_FAILURE(status) && status != AE_ALREADY_EXISTS) {
+		ACPI_EXCEPTION((AE_INFO, status,
+				"During Region initialization"));
+		return_ACPI_STATUS(status);
 	}
 
 	/* Load the namespace from the tables */

@@ -105,6 +103,20 @@ acpi_status __init acpi_load_tables(void)
 				"While loading namespace from ACPI tables"));
 	}
 
+	if (!acpi_gbl_group_module_level_code) {
+		/*
+		 * Initialize the objects that remain uninitialized. This
+		 * runs the executable AML that may be part of the
+		 * declaration of these objects:
+		 * operation_regions, buffer_fields, Buffers, and Packages.
+		 */
+		status = acpi_ns_initialize_objects();
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+	}
+
+	acpi_gbl_namespace_initialized = TRUE;
 	return_ACPI_STATUS(status);
 }
 

drivers/acpi/acpica/utxfinit.c +11 -32

index d70649d3ac60..75b5f27da267 100644
@@ -154,23 +154,6 @@ acpi_status __init acpi_enable_subsystem(u32 flags)
 	 */
 	acpi_gbl_early_initialization = FALSE;
 
-	/*
-	 * Install the default operation region handlers. These are the
-	 * handlers that are defined by the ACPI specification to be
-	 * "always accessible" -- namely, system_memory, system_IO, and
-	 * PCI_Config. This also means that no _REG methods need to be
-	 * run for these address spaces. We need to have these handlers
-	 * installed before any AML code can be executed, especially any
-	 * module-level code (11/2015).
-	 */
-	if (!acpi_gbl_group_module_level_code) {
-		status = acpi_ev_install_region_handlers();
-		if (ACPI_FAILURE(status)) {
-			ACPI_EXCEPTION((AE_INFO, status,
-					"During Region initialization"));
-			return_ACPI_STATUS(status);
-		}
-	}
 #if (!ACPI_REDUCED_HARDWARE)
 
 	/* Enable ACPI mode */

@@ -284,25 +267,21 @@ acpi_status __init acpi_initialize_objects(u32 flags)
 	 */
 	if (acpi_gbl_group_module_level_code) {
 		acpi_ns_exec_module_code_list();
-	}
 
-	/*
-	 * Initialize the objects that remain uninitialized. This runs the
-	 * executable AML that may be part of the declaration of these objects:
-	 * operation_regions, buffer_fields, Buffers, and Packages.
-	 */
-	if (!(flags & ACPI_NO_OBJECT_INIT)) {
-		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
-				  "[Init] Completing Initialization of ACPI
 Objects\n"));
-
-		status = acpi_ns_initialize_objects();
-		if (ACPI_FAILURE(status)) {
-			return_ACPI_STATUS(status);
+		/*
+		 * Initialize the objects that remain uninitialized. This
+		 * runs the executable AML that may be part of the
+		 * declaration of these objects:
+		 * operation_regions, buffer_fields, Buffers, and Packages.
+		 */
+		if (!(flags & ACPI_NO_OBJECT_INIT)) {
+			status = acpi_ns_initialize_objects();
+			if (ACPI_FAILURE(status)) {
+				return_ACPI_STATUS(status);
+			}
 		}
 	}
 
-	acpi_gbl_namespace_initialized = TRUE;
-
 	/*
 	 * Initialize all device/region objects in the namespace. This runs

* the device _STA and _INI methods and region _REG methods.