Merge branch 'master'

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/acpi/namespace/nsalloc.c b/drivers/acpi/namespace/nsalloc.c
index dc3f0739a46b..55b407aae266 100644
--- a/drivers/acpi/namespace/nsalloc.c
+++ b/drivers/acpi/namespace/nsalloc.c
@@ -386,14 +386,17 @@ void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
  *              specific ID.  Used to delete entire ACPI tables.  All
  *              reference counts are updated.
  *
+ * MUTEX:       Locks namespace during deletion walk.
+ *
  ******************************************************************************/
 
 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
 {
         struct acpi_namespace_node *child_node;
         struct acpi_namespace_node *deletion_node;
-        u32 level;
         struct acpi_namespace_node *parent_node;
+        u32 level;
+        acpi_status status;
 
         ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
 
@@ -401,6 +404,13 @@ void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
                 return_VOID;
         }
 
+        /* Lock namespace for possible update */
+
+        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+        if (ACPI_FAILURE(status)) {
+                return_VOID;
+        }
+
         deletion_node = NULL;
         parent_node = acpi_gbl_root_node;
         child_node = NULL;
@@ -469,5 +479,6 @@ void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
                 }
         }
 
+        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
         return_VOID;
 }