4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lv Zheng <lv.zheng@xxxxxxxxx> commit 5508df89756f8378024828e185724a9bd2348985 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/acpica/nsinit.c | 2 ++ drivers/acpi/acpica/tbxfload.c | 14 ++++++++++++++ drivers/acpi/acpica/utxfinit.c | 25 +++++++++++-------------- 3 files changed, 27 insertions(+), 14 deletions(-) --- a/drivers/acpi/acpica/nsinit.c +++ b/drivers/acpi/acpica/nsinit.c @@ -83,6 +83,8 @@ acpi_status acpi_ns_initialize_objects(v 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, --- a/drivers/acpi/acpica/tbxfload.c +++ b/drivers/acpi/acpica/tbxfload.c @@ -83,6 +83,20 @@ 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_reg_methods_enabled = TRUE; return_ACPI_STATUS(status); } --- a/drivers/acpi/acpica/utxfinit.c +++ b/drivers/acpi/acpica/utxfinit.c @@ -267,7 +267,6 @@ acpi_status __init acpi_initialize_objec * initialized, even if they contain executable AML (see the call to * acpi_ns_initialize_objects below). */ - acpi_gbl_reg_methods_enabled = TRUE; if (!(flags & ACPI_NO_ADDRESS_SPACE_INIT)) { ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[Init] Executing _REG OpRegion methods\n")); @@ -299,20 +298,18 @@ acpi_status __init acpi_initialize_objec */ 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); + } } } -- 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