bcache: Fix error handling in init code

[Dan Carpenter]

Hello Kent Overstreet,

This is a semi-automatic email about new static checker warnings.

The patch f59fce847fc8: "bcache: Fix error handling in init code"
from May 15, 2013, leads to the following Smatch complaint:

drivers/md/bcache/super.c:1088 cached_dev_free()
error: we previously assumed 'dc->bdev->bd_disk' could be null (see line 1085)

drivers/md/bcache/super.c
1084 if (!IS_ERR_OR_NULL(dc->bdev)) {
1085 if (dc->bdev->bd_disk)
^^^^^^^^^^^^^^^^^
The patch introduces a new check.

1086 blk_sync_queue(bdev_get_queue(dc->bdev));
1087
1088 blkdev_put(dc->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);

But "dc->bdev->bd_disk" is dereferenced inside the call to blkdev_put().

1089 }
1090

regards,
dan carpenter