5 files changed, 70 insertions, 26 deletions

diff --git a/drivers/acpi/acpica/actables.h b/drivers/acpi/acpica/actables.h
index bda9a7eb50c1..f14882788eee 100644
--- a/drivers/acpi/acpica/actables.h
+++ b/drivers/acpi/acpica/actables.h
@@ -69,6 +69,11 @@ acpi_tb_acquire_temp_table(struct acpi_table_desc *table_desc,
 
 void acpi_tb_release_temp_table(struct acpi_table_desc *table_desc);
 
+acpi_status acpi_tb_validate_temp_table(struct acpi_table_desc *table_desc);
+
+acpi_status
+acpi_tb_verify_temp_table(struct acpi_table_desc *table_desc, char *signature);
+
 u8 acpi_tb_is_table_loaded(u32 table_index);
 
 void acpi_tb_set_table_loaded_flag(u32 table_index, u8 is_loaded);
@@ -96,9 +101,6 @@ acpi_status acpi_tb_validate_table(struct acpi_table_desc *table_desc);
 
 void acpi_tb_invalidate_table(struct acpi_table_desc *table_desc);
 
-acpi_status
-acpi_tb_verify_table(struct acpi_table_desc *table_desc, char *signature);
-
 void acpi_tb_override_table(struct acpi_table_desc *old_table_desc);
 
 acpi_status
diff --git a/drivers/acpi/acpica/tbdata.c b/drivers/acpi/acpica/tbdata.c
index cbe29944dc97..f499c10ceb4a 100644
--- a/drivers/acpi/acpica/tbdata.c
+++ b/drivers/acpi/acpica/tbdata.c
@@ -322,7 +322,39 @@ void acpi_tb_invalidate_table(struct acpi_table_desc *table_desc)
 
 /******************************************************************************
  *
- * FUNCTION:    acpi_tb_verify_table
+ * FUNCTION:    acpi_tb_validate_temp_table
+ *
+ * PARAMETERS:  table_desc          - Table descriptor
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: This function is called to validate the table, the returned
+ *              table descriptor is in "VALIDATED" state.
+ *
+ *****************************************************************************/
+
+acpi_status acpi_tb_validate_temp_table(struct acpi_table_desc *table_desc)
+{
+
+        if (!table_desc->pointer && !acpi_gbl_verify_table_checksum) {
+                /*
+                 * Only validates the header of the table.
+                 * Note that Length contains the size of the mapping after invoking
+                 * this work around, this value is required by
+                 * acpi_tb_release_temp_table().
+                 * We can do this because in acpi_init_table_descriptor(), the Length
+                 * field of the installed descriptor is filled with the actual
+                 * table length obtaining from the table header.
+                 */
+                table_desc->length = sizeof(struct acpi_table_header);
+        }
+
+        return (acpi_tb_validate_table(table_desc));
+}
+
+/******************************************************************************
+ *
+ * FUNCTION:    acpi_tb_verify_temp_table
  *
  * PARAMETERS:  table_desc          - Table descriptor
  *              signature           - Table signature to verify
@@ -335,15 +367,15 @@ void acpi_tb_invalidate_table(struct acpi_table_desc *table_desc)
  *****************************************************************************/
 
 acpi_status
-acpi_tb_verify_table(struct acpi_table_desc *table_desc, char *signature)
+acpi_tb_verify_temp_table(struct acpi_table_desc * table_desc, char *signature)
 {
         acpi_status status = AE_OK;
 
-        ACPI_FUNCTION_TRACE(tb_verify_table);
+        ACPI_FUNCTION_TRACE(tb_verify_temp_table);
 
         /* Validate the table */
 
-        status = acpi_tb_validate_table(table_desc);
+        status = acpi_tb_validate_temp_table(table_desc);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(AE_NO_MEMORY);
         }
@@ -360,17 +392,22 @@ acpi_tb_verify_table(struct acpi_table_desc *table_desc, char *signature)
 
         /* Verify the checksum */
 
-        status =
-            acpi_tb_verify_checksum(table_desc->pointer, table_desc->length);
-        if (ACPI_FAILURE(status)) {
-                ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY,
-                                "%4.4s " ACPI_PRINTF_UINT
-                                " Attempted table install failed",
-                                acpi_ut_valid_acpi_name(table_desc->signature.
-                                                        ascii) ? table_desc->
-                                signature.ascii : "????",
-                                ACPI_FORMAT_TO_UINT(table_desc->address)));
-                goto invalidate_and_exit;
+        if (acpi_gbl_verify_table_checksum) {
+                status =
+                    acpi_tb_verify_checksum(table_desc->pointer,
+                                            table_desc->length);
+                if (ACPI_FAILURE(status)) {
+                        ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY,
+                                        "%4.4s " ACPI_PRINTF_UINT
+                                        " Attempted table install failed",
+                                        acpi_ut_valid_acpi_name(table_desc->
+                                                                signature.
+                                                                ascii) ?
+                                        table_desc->signature.ascii : "????",
+                                        ACPI_FORMAT_TO_UINT(table_desc->
+                                                            address)));
+                        goto invalidate_and_exit;
+                }
         }
 
         return_ACPI_STATUS(AE_OK);
diff --git a/drivers/acpi/acpica/tbinstal.c b/drivers/acpi/acpica/tbinstal.c
index d4d6029fef44..755b90c40ddf 100644
--- a/drivers/acpi/acpica/tbinstal.c
+++ b/drivers/acpi/acpica/tbinstal.c
@@ -194,7 +194,7 @@ acpi_tb_install_fixed_table(acpi_physical_address address,
 
         /* Validate and verify a table before installation */
 
-        status = acpi_tb_verify_table(&new_table_desc, signature);
+        status = acpi_tb_verify_temp_table(&new_table_desc, signature);
         if (ACPI_FAILURE(status)) {
                 goto release_and_exit;
         }
@@ -266,7 +266,7 @@ acpi_tb_install_standard_table(acpi_physical_address address,
 
         /* Validate and verify a table before installation */
 
-        status = acpi_tb_verify_table(&new_table_desc, NULL);
+        status = acpi_tb_verify_temp_table(&new_table_desc, NULL);
         if (ACPI_FAILURE(status)) {
                 goto release_and_exit;
         }
@@ -424,7 +424,7 @@ finish_override:
 
         /* Validate and verify a table before overriding */
 
-        status = acpi_tb_verify_table(&new_table_desc, NULL);
+        status = acpi_tb_verify_temp_table(&new_table_desc, NULL);
         if (ACPI_FAILURE(status)) {
                 return;
         }
@@ -446,7 +446,7 @@ finish_override:
         acpi_tb_init_table_descriptor(old_table_desc, new_table_desc.address,
                                       new_table_desc.flags,
                                       new_table_desc.pointer);
-        acpi_tb_validate_table(old_table_desc);
+        acpi_tb_validate_temp_table(old_table_desc);
 
         /* Release the temporary table descriptor */
 
diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c
index e37a103013a4..6b1ca9991b90 100644
--- a/drivers/acpi/acpica/tbutils.c
+++ b/drivers/acpi/acpica/tbutils.c
@@ -395,10 +395,6 @@ next_table:
                 table_entry += table_entry_size;
         }
 
-        /*
-         * It is not possible to map more than one entry in some environments,
-         * so unmap the root table here before mapping other tables
-         */
         acpi_os_unmap_memory(table, length);
 
         return_ACPI_STATUS(AE_OK);
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index b5f7132f431f..35b525c19711 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -162,6 +162,15 @@ ACPI_INIT_GLOBAL(u8, acpi_gbl_create_osi_method, TRUE);
 ACPI_INIT_GLOBAL(u8, acpi_gbl_use_default_register_widths, TRUE);
 
 /*
+ * Whether or not to verify the table checksum before installation. Set
+ * this to TRUE to verify the table checksum before install it to the table
+ * manager. Note that enabling this option causes errors to happen in some
+ * OSPMs during early initialization stages. Default behavior is to do such
+ * verification.
+ */
+ACPI_INIT_GLOBAL(u8, acpi_gbl_verify_table_checksum, TRUE);
+
+/*
  * Optionally enable output from the AML Debug Object.
  */
 ACPI_INIT_GLOBAL(u8, acpi_gbl_enable_aml_debug_object, FALSE);