Panic can be seen when OS runs _PDC from different CPUs to dynamically "Load" the tables. And this is because acpi_tb_validate_table() is an early stage only API and cannot be deployed to the racing environment. While here we want the table to be transitioned into the "VALIDATED" state before being transitioned into "LOADED" state, so acpi_tb_validate_table_by_index() is actually the proper API that should be invoked here and it properly locks the table descriptor with MTX_TABLES mutex. Lv Zheng. Link: https://bugs.acpica.org/show_bug.cgi?id=1254 Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> --- drivers/acpi/acpica/exconfig.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/acpica/exconfig.c b/drivers/acpi/acpica/exconfig.c index 98102af..3418c90 100644 --- a/drivers/acpi/acpica/exconfig.c +++ b/drivers/acpi/acpica/exconfig.c @@ -493,10 +493,12 @@ acpi_ex_load_op(union acpi_operand_object *obj_desc, /* * Note: Now table is "INSTALLED", it must be validated before * loading. + * As Table pointer has been installed, no code from here will still be + * using the original pointer. Furthermore, the table handler actually + * wants a validation result of the table. So this pointer is refilled + * by the returning value of acpi_tb_validate_table_by_index(). */ - status = - acpi_tb_validate_table(&acpi_gbl_root_table_list. - tables[table_index]); + status = acpi_tb_validate_table_by_index(table_index, &table); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
