4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Erik Schmauss <erik.schma...@intel.com>

commit 460a53106ac39b74625d1104d9a113e0f3716c18 upstream.

Previous change in the AML parser code blindly set all non-successful
dispatcher statuses to AE_OK. That approach is incorrect, though,
because successful control method invocations from module-level
return AE_CTRL_TRANSFER. Overwriting AE_OK to this status causes the
AML parser to think that there was no return value from the control
method invocation.

Fixes: 92c0f4af386 (ACPICA: AML Parser: ignore dispatcher error status during 
table load)
Reported-by: Linus Torvalds <torva...@linux-foundation.org>
Tested-by: Linus Torvalds <torva...@linux-foundation.org>
Tested-by: Oleksandr Natalenko <oleksa...@natalenko.name>
Signed-off-by: Erik Schmauss <erik.schma...@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/acpi/acpica/psloop.c |   19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

--- a/drivers/acpi/acpica/psloop.c
+++ b/drivers/acpi/acpica/psloop.c
@@ -709,15 +709,20 @@ acpi_status acpi_ps_parse_loop(struct ac
                        } else
                            if ((walk_state->
                                 parse_flags & ACPI_PARSE_MODULE_LEVEL)
+                               && status != AE_CTRL_TRANSFER
                                && ACPI_FAILURE(status)) {
                                /*
-                                * ACPI_PARSE_MODULE_LEVEL means that we are 
loading a table by
-                                * executing it as a control method. However, 
if we encounter
-                                * an error while loading the table, we need to 
keep trying to
-                                * load the table rather than aborting the 
table load. Set the
-                                * status to AE_OK to proceed with the table 
load. If we get a
-                                * failure at this point, it means that the 
dispatcher got an
-                                * error while processing Op (most likely an 
AML operand error.
+                                * ACPI_PARSE_MODULE_LEVEL flag means that we 
are currently
+                                * loading a table by executing it as a control 
method.
+                                * However, if we encounter an error while 
loading the table,
+                                * we need to keep trying to load the table 
rather than
+                                * aborting the table load (setting the status 
to AE_OK
+                                * continues the table load). If we get a 
failure at this
+                                * point, it means that the dispatcher got an 
error while
+                                * processing Op (most likely an AML operand 
error) or a
+                                * control method was called from module level 
and the
+                                * dispatcher returned AE_CTRL_TRANSFER. In the 
latter case,
+                                * leave the status alone, there's nothing 
wrong with it.
                                 */
                                status = AE_OK;
                        }


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