diff --git a/fs/afs/dynroot.c b/fs/afs/dynroot.c
index 691e0ae607a1..61bc8c81c5ca 100644
--- a/fs/afs/dynroot.c
+++ b/fs/afs/dynroot.c
@@ -348,9 +348,9 @@ static int afs_dynroot_readdir(struct file *file, struct dir_context *ctx)
 	}
 
 	if ((unsigned long long)ctx->pos <= AFS_MAX_DYNROOT_CELL_INO) {
-		rcu_read_lock();
+		down_read(&file_inode(file)->i_rwsem);
 		ret = afs_dynroot_readdir_cells(net, ctx);
-		rcu_read_unlock();
+		up_read(&file_inode(file)->i_rwsem);
 	}
 	return ret;
 }