ACPICA: Disassembler: create buffer fields in ACPI_PARSE_LOAD_PASS1

[ Upstream commit 5ddbd77181dfca61b16d2e2222382ea65637f1b9 ]

ACPICA commit 29cc8dbc5463a93625bed87d7550a8bed8913bf4

create_buffer_field is a deferred op that is typically processed in
load pass 2. However, disassembly of control method contents walk the
parse tree with ACPI_PARSE_LOAD_PASS1 and AML_CREATE operators are
processed in a later walk. This is a problem when there is a control
method that has the same name as the AML_CREATE object. In this case,
any use of the name segment will be detected as a method call rather
than a reference to a buffer field. If this is detected as a method
call, it can result in a mal-formed parse tree if the control methods
have parameters.

This change in processing AML_CREATE ops earlier solves this issue by
inserting the named object in the ACPI namespace so that references
to this name would be detected as a name string rather than a method
call.

Link: https://github.com/acpica/acpica/commit/29cc8dbc
Reported-by: Elia Geretto <elia.f.geretto@gmail.com>
Tested-by: Elia Geretto <elia.f.geretto@gmail.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Erik Kaneda <erik.kaneda@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/acpi/acpica/dsfield.c b/drivers/acpi/acpica/dsfield.c
index 30fe895..bcc6a7a 100644 (file)
--- a/drivers/acpi/acpica/dsfield.c
+++ b/drivers/acpi/acpica/dsfield.c
@@ -244,7 +244,7 @@ cleanup:
  * FUNCTION:    acpi_ds_get_field_names
  *
  * PARAMETERS:  info            - create_field info structure
- *  `           walk_state      - Current method state
+ *              walk_state      - Current method state
  *              arg             - First parser arg for the field name list
  *
  * RETURN:      Status

diff --git a/drivers/acpi/acpica/dswload.c b/drivers/acpi/acpica/dswload.c
index d06c414..ba53662 100644 (file)
--- a/drivers/acpi/acpica/dswload.c
+++ b/drivers/acpi/acpica/dswload.c
@@ -412,6 +412,27 @@ acpi_status acpi_ds_load1_end_op(struct acpi_walk_state *walk_state)
        ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Op=%p State=%p\n", op,
                          walk_state));
 
+       /*
+        * Disassembler: handle create field operators here.
+        *
+        * create_buffer_field is a deferred op that is typically processed in load
+        * pass 2. However, disassembly of control method contents walk the parse
+        * tree with ACPI_PARSE_LOAD_PASS1 and AML_CREATE operators are processed
+        * in a later walk. This is a problem when there is a control method that
+        * has the same name as the AML_CREATE object. In this case, any use of the
+        * name segment will be detected as a method call rather than a reference
+        * to a buffer field.
+        *
+        * This earlier creation during disassembly solves this issue by inserting
+        * the named object in the ACPI namespace so that references to this name
+        * would be a name string rather than a method call.
+        */
+       if ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) &&
+           (walk_state->op_info->flags & AML_CREATE)) {
+               status = acpi_ds_create_buffer_field(op, walk_state);
+               return_ACPI_STATUS(status);
+       }
+
        /* We are only interested in opcodes that have an associated name */
 
        if (!(walk_state->op_info->flags & (AML_NAMED | AML_FIELD))) {