1 files changed, 69 insertions, 13 deletions

diff --git a/drivers/acpi/acpica/tbinstal.c b/drivers/acpi/acpica/tbinstal.c
index 37374b21969d..f865d5a096de 100644
--- a/drivers/acpi/acpica/tbinstal.c
+++ b/drivers/acpi/acpica/tbinstal.c
@@ -103,7 +103,9 @@ acpi_status acpi_tb_verify_table(struct acpi_table_desc *table_desc)
  *
  * RETURN:      Status
  *
- * DESCRIPTION: This function is called to add the ACPI table
+ * DESCRIPTION: This function is called to add an ACPI table. It is used to
+ *              dynamically load tables via the Load and load_table AML
+ *              operators.
  *
  ******************************************************************************/
 
@@ -112,6 +114,7 @@ acpi_tb_add_table(struct acpi_table_desc *table_desc, u32 *table_index)
 {
         u32 i;
         acpi_status status = AE_OK;
+        struct acpi_table_header *override_table = NULL;
 
         ACPI_FUNCTION_TRACE(tb_add_table);
 
@@ -201,6 +204,29 @@ acpi_tb_add_table(struct acpi_table_desc *table_desc, u32 *table_index)
                 }
         }
 
+        /*
+         * ACPI Table Override:
+         * Allow the host to override dynamically loaded tables.
+         */
+        status = acpi_os_table_override(table_desc->pointer, &override_table);
+        if (ACPI_SUCCESS(status) && override_table) {
+                ACPI_INFO((AE_INFO,
+                           "%4.4s @ 0x%p Table override, replaced with:",
+                           table_desc->pointer->signature,
+                           ACPI_CAST_PTR(void, table_desc->address)));
+
+                /* We can delete the table that was passed as a parameter */
+
+                acpi_tb_delete_table(table_desc);
+
+                /* Setup descriptor for the new table */
+
+                table_desc->address = ACPI_PTR_TO_PHYSADDR(override_table);
+                table_desc->pointer = override_table;
+                table_desc->length = override_table->length;
+                table_desc->flags = ACPI_TABLE_ORIGIN_OVERRIDE;
+        }
+
         /* Add the table to the global root table list */
 
         status = acpi_tb_store_table(table_desc->address, table_desc->pointer,
@@ -247,8 +273,9 @@ acpi_status acpi_tb_resize_root_table_list(void)
         /* Increase the Table Array size */
 
         tables = ACPI_ALLOCATE_ZEROED(((acpi_size) acpi_gbl_root_table_list.
-                                       size + ACPI_ROOT_TABLE_SIZE_INCREMENT)
-                                      * sizeof(struct acpi_table_desc));
+                                       size +
+                                       ACPI_ROOT_TABLE_SIZE_INCREMENT) *
+                                      sizeof(struct acpi_table_desc));
         if (!tables) {
                 ACPI_ERROR((AE_INFO,
                             "Could not allocate new root table array"));
@@ -407,27 +434,56 @@ void acpi_tb_terminate(void)
  *
  * PARAMETERS:  table_index         - Table index
  *
- * RETURN:      None
+ * RETURN:      Status
  *
  * DESCRIPTION: Delete all namespace objects created when this table was loaded.
  *
  ******************************************************************************/
 
-void acpi_tb_delete_namespace_by_owner(u32 table_index)
+acpi_status acpi_tb_delete_namespace_by_owner(u32 table_index)
 {
         acpi_owner_id owner_id;
+        acpi_status status;
+
+        ACPI_FUNCTION_TRACE(tb_delete_namespace_by_owner);
+
+        status = acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
+
+        if (table_index >= acpi_gbl_root_table_list.count) {
+
+                /* The table index does not exist */
 
-        (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
-        if (table_index < acpi_gbl_root_table_list.count) {
-                owner_id =
-                    acpi_gbl_root_table_list.tables[table_index].owner_id;
-        } else {
                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
-                return;
+                return_ACPI_STATUS(AE_NOT_EXIST);
         }
 
+        /* Get the owner ID for this table, used to delete namespace nodes */
+
+        owner_id = acpi_gbl_root_table_list.tables[table_index].owner_id;
         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
+
+        /*
+         * Need to acquire the namespace writer lock to prevent interference
+         * with any concurrent namespace walks. The interpreter must be
+         * released during the deletion since the acquisition of the deletion
+         * lock may block, and also since the execution of a namespace walk
+         * must be allowed to use the interpreter.
+         */
+        acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
+        status = acpi_ut_acquire_write_lock(&acpi_gbl_namespace_rw_lock);
+
         acpi_ns_delete_namespace_by_owner(owner_id);
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
+
+        acpi_ut_release_write_lock(&acpi_gbl_namespace_rw_lock);
+
+        status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
+        return_ACPI_STATUS(status);
 }
 
 /*******************************************************************************
@@ -535,8 +591,8 @@ u8 acpi_tb_is_table_loaded(u32 table_index)
         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
         if (table_index < acpi_gbl_root_table_list.count) {
                 is_loaded = (u8)
-                    (acpi_gbl_root_table_list.tables[table_index].
-                     flags & ACPI_TABLE_IS_LOADED);
+                    (acpi_gbl_root_table_list.tables[table_index].flags &
+                     ACPI_TABLE_IS_LOADED);
         }
 
         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);