Merge tag 'driver-core-4.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fix from Greg KH:
 "Here is a single kernfs fix for 4.11-rc4 that resolves a reported
  issue.

  It has been in linux-next with no reported issues"

* tag 'driver-core-4.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kernfs: Check KERNFS_HAS_RELEASE before calling kernfs_release_file()
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index 8e4dc7a..ac2dfe0 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -809,7 +809,8 @@
 		if (kn->flags & KERNFS_HAS_MMAP)
 			unmap_mapping_range(inode->i_mapping, 0, 0, 1);
 
-		kernfs_release_file(kn, of);
+		if (kn->flags & KERNFS_HAS_RELEASE)
+			kernfs_release_file(kn, of);
 	}
 
 	mutex_unlock(&kernfs_open_file_mutex);