1 files changed, 3 insertions, 1 deletions

diff --git a/fs/char_dev.c b/fs/char_dev.c
index f80a4f25123c..143d393881cb 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -40,7 +40,9 @@ struct backing_dev_info directly_mappable_cdev_bdi = {
 #endif
                 /* permit direct mmap, for read, write or exec */
                 BDI_CAP_MAP_DIRECT |
-                BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP),
+                BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP |
+                /* no writeback happens */
+                BDI_CAP_NO_ACCT_AND_WRITEBACK),
 };
 
 static struct kobj_map *cdev_map;