From: Anton Vorontsov <cbou@mail.ru>

Because add_disk() getting driverfs_dev twice but putting it only once,
ide-{disk,cd,floppy} should put_device() themselfs. This is workaround
for the bug found in genhd, which causes deadlock in ide_unregister()
at wait_for_completion(&drive->gendev_rel_comp) after
device_unregister(&drive->gendev). That happens by reason of
ide-probe.c:drive_release_dev() not called because of driverfs_dev
(which is drive->gendev) still referenced by add_disk().

diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index bddfebd..59121a3 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -3307,6 +3307,7 @@ static void ide_cd_release(struct kref *
 	blk_queue_prep_rq(drive->queue, NULL);
 	g->private_data = NULL;
 	put_disk(g);
+	put_device(&drive->gendev);
 	kfree(info);
 }
 
diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c
index 0a05a37..d5d02a1 100644
--- a/drivers/ide/ide-disk.c
+++ b/drivers/ide/ide-disk.c
@@ -1020,6 +1020,7 @@ static void ide_disk_release(struct kref
 	drive->driver_data = NULL;
 	g->private_data = NULL;
 	put_disk(g);
+	put_device(&drive->gendev);
 	kfree(idkp);
 }
 
diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 8ccee9c..7a60d8c 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -1887,6 +1887,7 @@ static void ide_floppy_release(struct kr
 	drive->driver_data = NULL;
 	g->private_data = NULL;
 	put_disk(g);
+	put_device(&drive->gendev);
 	kfree(floppy);
 }