1 files changed, 25 insertions, 4 deletions

diff --git a/drivers/acpi/dispatcher/dsopcode.c b/drivers/acpi/dispatcher/dsopcode.c
index 69fae5905bb8..5cd406676c2c 100644
--- a/drivers/acpi/dispatcher/dsopcode.c
+++ b/drivers/acpi/dispatcher/dsopcode.c
@@ -1140,10 +1140,29 @@ acpi_ds_exec_begin_control_op(struct acpi_walk_state *walk_state,
                           op->common.aml_opcode, walk_state));
 
         switch (op->common.aml_opcode) {
-        case AML_IF_OP:
         case AML_WHILE_OP:
 
                 /*
+                 * If this is an additional iteration of a while loop, continue.
+                 * There is no need to allocate a new control state.
+                 */
+                if (walk_state->control_state) {
+                        if (walk_state->control_state->control.aml_predicate_start
+                                == (walk_state->parser_state.aml - 1)) {
+
+                                /* Reset the state to start-of-loop */
+
+                                walk_state->control_state->common.state =
+                                    ACPI_CONTROL_CONDITIONAL_EXECUTING;
+                                break;
+                        }
+                }
+
+                /*lint -fallthrough */
+
+        case AML_IF_OP:
+
+                /*
                  * IF/WHILE: Create a new control state to manage these
                  * constructs. We need to manage these as a stack, in order
                  * to handle nesting.
@@ -1248,8 +1267,13 @@ acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
                         /* Predicate was true, go back and evaluate it again! */
 
                         status = AE_CTRL_PENDING;
+                        walk_state->aml_last_while =
+                            walk_state->control_state->control.aml_predicate_start;
+                        break;
                 }
 
+                /* Predicate was false, terminate this while loop */
+
                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
                                   "[WHILE_OP] termination! Op=%p\n", op));
 
@@ -1257,9 +1281,6 @@ acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
 
                 control_state =
                     acpi_ut_pop_generic_state(&walk_state->control_state);
-
-                walk_state->aml_last_while =
-                    control_state->control.aml_predicate_start;
                 acpi_ut_delete_generic_state(control_state);
                 break;