ACPI / sysfs: Fix an issue for LoadTable opcode
OEM tables can be installed via RSDT/XSDT, in this case, they have already been created under /sys/firmware/acpi/tables. For this kind of tables, normally LoadTable opcode will be executed to load them. If LoadTable opcode is executed after acpi_sysfs_init(), acpi_sysfs_table_handler() will be invoked, thus a redundant table file will be created under /sys/firmware/acpi/tables/dynamic. Then running "acpidump" on such platform results in an error, complaining blank empty table (see Link 1 below). The bug can be reproduced by customizing an OEM1 table, allowing it to be overridden via 'table_sigs' (drivers/acpi/tables.c), adding the following code to the customized DSDT to load it: Name (OEMH, Zero) Name (OEMF, One) If (LEqual (OEMF, One)) { Store (LoadTable ("OEM1", "Intel", "Test"), OEMH) Store (Zero, OEMF) } In order to make sure that the OEM1 table is installed after acpi_sysfs_init(), acpi_sysfs_init() can be moved before invoking acpi_load_tables(). Then the following command execution result can be seen: # acpidump > acpidump.txt Could not read table header: /sysfs/firmware/acpi/tables/dynamic/OEM12 Could not get ACPI table at index 17, AE_BAD_HEADER Link: https://bugzilla.kernel.org/show_bug.cgi?id=150841 # [1] Link: https://github.com/acpica/acpica/commit/ed6a5fbcReported-by: NJason Voelz <jason.voelz@intel.com> Reported-by: NFrancisco Leoner <francisco.j.lenoer.soto@intel.com> Signed-off-by: NLv Zheng <lv.zheng@intel.com> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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