Merge tag 'md/4.0-rc4-fix' of git://neil.brown.name/md

Pull bugfix for md from Neil Brown:
 "One fix for md in 4.0-rc4

  Regression in recent patch causes crash on error path"

* tag 'md/4.0-rc4-fix' of git://neil.brown.name/md:
  md: fix problems with freeing private data after ->run failure.

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index cadf9cc02b25..717daad71fb1 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5080,7 +5080,8 @@ int md_run(struct mddev *mddev)
         }
         if (err) {
                 mddev_detach(mddev);
-                pers->free(mddev, mddev->private);
+                if (mddev->private)
+                        pers->free(mddev, mddev->private);
                 module_put(pers->owner);
                 bitmap_destroy(mddev);
                 return err;