ACPICA: Debugger: Lock namespace for duration of a namespace dump

Prevents issues if the namespace is changing underneath the
debugger.  Especially temporary nodes, since the debugger displays
these also.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Reviewed-by: Rafael Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/nsdump.c b/drivers/acpi/acpica/nsdump.c
index a54dc39e304b..82693c3eb257 100644
--- a/drivers/acpi/acpica/nsdump.c
+++ b/drivers/acpi/acpica/nsdump.c
@@ -624,9 +624,22 @@ acpi_ns_dump_objects(acpi_object_type type,
                      acpi_owner_id owner_id, acpi_handle start_handle)
 {
         struct acpi_walk_info info;
+        acpi_status status;
 
         ACPI_FUNCTION_ENTRY();
 
+        /*
+         * Just lock the entire namespace for the duration of the dump.
+         * We don't want any changes to the namespace during this time,
+         * especially the temporary nodes since we are going to display
+         * them also.
+         */
+        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+        if (ACPI_FAILURE(status)) {
+                acpi_os_printf("Could not acquire namespace mutex\n");
+                return;
+        }
+
         info.debug_level = ACPI_LV_TABLES;
         info.owner_id = owner_id;
         info.display_type = display_type;
@@ -636,6 +649,8 @@ acpi_ns_dump_objects(acpi_object_type type,
                                      ACPI_NS_WALK_TEMP_NODES,
                                      acpi_ns_dump_one_object, NULL,
                                      (void *)&info, NULL);
+
+        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 }
 #endif                          /* ACPI_FUTURE_USAGE */