ACPICA: Tables: Fix multiple ACPI_FREE()s around acpi_tb_add_table().

Currently there are following issues in acpi_tb_add_table():
Following logic is currently correct:
1. When a table is allocated in acpi_ex_load_op(), if a reloading happens,
   the allocated memory is freed by acpi_tb_add_table() and AE_OK is
   returned to the caller to avoid the caller to free it again.
Following logic is currently incorrect:
1. When a table is allocated in acpi_ex_load_op() or by the
   acpi_load_table() caller, if the table is already loaded, there will be
   twice ACPI_FREE() called for the same pointer when acpi_tb_add_table()
   returns AE_ALREADY_EXISTS.

This patch only fixes the above incorrect logic in acpi_tb_add_table():
1. Only invoke acpi_tb_delete_table() if AE_OK is going to be returned.
2. After doing so, we do not invoke ACPI_FREE() when returning AE_OK;

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

2 files changed, 2 insertions, 7 deletions

diff --git a/drivers/acpi/acpica/exconfig.c b/drivers/acpi/acpica/exconfig.c
index 649a8efef0f5..11a014ca3935 100644
--- a/drivers/acpi/acpica/exconfig.c
+++ b/drivers/acpi/acpica/exconfig.c
@@ -504,7 +504,7 @@ acpi_ex_load_op(union acpi_operand_object *obj_desc,
 
                 /* Delete allocated table buffer */
 
-                acpi_tb_delete_table(&table_desc);
+                ACPI_FREE(table_desc.pointer);
                 return_ACPI_STATUS(status);
         }
 
diff --git a/drivers/acpi/acpica/tbinstal.c b/drivers/acpi/acpica/tbinstal.c
index 144076ac21f0..0040e19b6d14 100644
--- a/drivers/acpi/acpica/tbinstal.c
+++ b/drivers/acpi/acpica/tbinstal.c
@@ -203,12 +203,6 @@ acpi_tb_add_table(struct acpi_table_desc *table_desc, u32 *table_index)
                  * need to be unregistered when they are unloaded, and slots in the
                  * root table list should be reused when empty.
                  */
-
-                /*
-                 * Table is already registered.
-                 * We can delete the table that was passed as a parameter.
-                 */
-                acpi_tb_delete_table(table_desc);
                 *table_index = i;
 
                 if (acpi_gbl_root_table_list.tables[i].
@@ -221,6 +215,7 @@ acpi_tb_add_table(struct acpi_table_desc *table_desc, u32 *table_index)
                 } else {
                         /* Table was unloaded, allow it to be reloaded */
 
+                        acpi_tb_delete_table(table_desc);
                         table_desc->pointer =
                             acpi_gbl_root_table_list.tables[i].pointer;
                         table_desc->address =