ACPICA: Add repair for bad _MAT buffers

_MAT can inadvertently return an Integer instead of a Buffer
if the return value has been read from a Field whose width is
less than or equal to the global integer width (32 or 64 bits).
ACPICA BZ 810.

http://www.acpica.org/bugzilla/show_bug.cgi?id=810

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Lin Ming 2009-10-13 10:23:20 +08:00 committed by Len Brown
parent 2752699392
commit 0240d7b4f2

View File

@ -44,6 +44,7 @@
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acinterp.h"
#include "acpredef.h"
#define _COMPONENT ACPI_NAMESPACE
@ -76,6 +77,7 @@ acpi_ns_repair_object(struct acpi_predefined_data *data,
union acpi_operand_object *return_object = *return_object_ptr;
union acpi_operand_object *new_object;
acpi_size length;
acpi_status status;
/*
* At this point, we know that the type of the returned object was not
@ -120,9 +122,26 @@ acpi_ns_repair_object(struct acpi_predefined_data *data,
case ACPI_TYPE_INTEGER:
/* Does the method/object legally return a string? */
/* 1) Does the method/object legally return a buffer? */
if (expected_btypes & ACPI_RTYPE_STRING) {
if (expected_btypes & ACPI_RTYPE_BUFFER) {
/*
* Convert the Integer to a packed-byte buffer. _MAT needs
* this sometimes, if a read has been performed on a Field
* object that is less than or equal to the global integer
* size (32 or 64 bits).
*/
status =
acpi_ex_convert_to_buffer(return_object,
&new_object);
if (ACPI_FAILURE(status)) {
return (status);
}
}
/* 2) Does the method/object legally return a string? */
else if (expected_btypes & ACPI_RTYPE_STRING) {
/*
* The only supported Integer-to-String conversion is to convert
* an integer of value 0 to a NULL string. The last element of