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 <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 5508df89756f8378024828e185724a9bd2348985 Mon Sep 17 00:00:00 2001 From: Lv Zheng <lv.zheng@xxxxxxxxx> 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 <chris.bainbridge@xxxxxxxxx> Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> diff --git a/drivers/acpi/acpica/nsinit.c b/drivers/acpi/acpica/nsinit.c index f029a3da67eb..d4aa8b696ee9 100644 --- a/drivers/acpi/acpica/nsinit.c +++ b/drivers/acpi/acpica/nsinit.c @@ -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")); ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT, diff --git a/drivers/acpi/acpica/tbxfload.c b/drivers/acpi/acpica/tbxfload.c index 9496b84476a4..3151968c10d1 100644 --- a/drivers/acpi/acpica/tbxfload.c +++ b/drivers/acpi/acpica/tbxfload.c @@ -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); } diff --git a/drivers/acpi/acpica/utxfinit.c b/drivers/acpi/acpica/utxfinit.c index d70649d3ac60..75b5f27da267 100644 --- a/drivers/acpi/acpica/utxfinit.c +++ b/drivers/acpi/acpica/utxfinit.c @@ -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. -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html