From c6c6069cad37952da71d2a24eb6ee0a87074b35c Mon Sep 17 00:00:00 2001 From: Bob Moore Date: Tue, 29 Dec 2015 13:56:14 +0800 Subject: [PATCH] ACPICA: Add comment explaining _SUB removal ACPICA commit 81a89968f83bfc3b1d0f0f80f2da08ea69646053 Adds a lengthy comment to acpi_get_object_info explaining the removal of _SUB and why no complex methods can be added ever to this interface. Link: https://github.com/acpica/acpica/commit/81a89968 Signed-off-by: Bob Moore Signed-off-by: Lv Zheng Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/nsxfname.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/acpi/acpica/nsxfname.c b/drivers/acpi/acpica/nsxfname.c index 0e4e6b7983cc..669e0f1b0967 100644 --- a/drivers/acpi/acpica/nsxfname.c +++ b/drivers/acpi/acpica/nsxfname.c @@ -267,6 +267,13 @@ static char *acpi_ns_copy_device_id(struct acpi_pnp_device_id *dest, * * Note: Allocates the return buffer, must be freed by the caller. * + * Note: This interface is intended to be used during the initial device + * discovery namespace traversal. Therefore, no complex methods can be + * executed, especially those that access operation regions. Therefore, do + * not add any additional methods that could cause problems in this area. + * this was the fate of the _SUB method which was found to cause such + * problems and was removed (11/2015). + * ******************************************************************************/ acpi_status -- 2.20.1