ACPICA: Interpreter: Add warning if 64-bit constant appears in 32-bit table.

Some ASL compilers allow 64-bit constants within a 32-bit table
(DSDT version == 1). When encountered, emit a warning that the
constant will be truncated to 32 bits. This is potentially a
serious problem in the ACPI table(s).

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/drivers/acpi/acpica/dsobject.c b/drivers/acpi/acpica/dsobject.c
index 13844a115d97..82050bcd90e7 100644
--- a/drivers/acpi/acpica/dsobject.c
+++ b/drivers/acpi/acpica/dsobject.c
@@ -703,7 +703,7 @@ acpi_ds_init_object_from_op(struct acpi_walk_state *walk_state,
                                 /* Truncate value if we are executing from a 32-bit ACPI table */
 
 #ifndef ACPI_NO_METHOD_EXECUTION
-                                acpi_ex_truncate_for32bit_table(obj_desc);
+                                (void)acpi_ex_truncate_for32bit_table(obj_desc);
 #endif
                                 break;
 
@@ -725,8 +725,18 @@ acpi_ds_init_object_from_op(struct acpi_walk_state *walk_state,
                 case AML_TYPE_LITERAL:
 
                         obj_desc->integer.value = op->common.value.integer;
+
 #ifndef ACPI_NO_METHOD_EXECUTION
-                        acpi_ex_truncate_for32bit_table(obj_desc);
+                        if (acpi_ex_truncate_for32bit_table(obj_desc)) {
+
+                                /* Warn if we found a 64-bit constant in a 32-bit table */
+
+                                ACPI_WARNING((AE_INFO,
+                                              "Truncated 64-bit constant found in 32-bit table: %8.8X%8.8X => %8.8X",
+                                              ACPI_FORMAT_UINT64(op->common.
+                                                                 value.integer),
+                                              (u32)obj_desc->integer.value));
+                        }
 #endif
                         break;