Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull final block layer fixes from Jens Axboe:
 "Unfortunately the hctx/ctx lifetime fix from last pull had some
  issues.  This pull request contains a revert of the problematic
  commit, and a proper rewrite of it.

  The rewrite has been tested by the users complaining about the
  regression, and it works fine now.  Additionally, I've run testing on
  all the blk-mq use cases for it and it passes.  So we should
  definitely get this into 3.19, to avoid regression for some cases"

* 'for-linus' of git://git.kernel.dk/linux-block:
  blk-mq: release mq's kobjects in blk_release_queue()
  Revert "blk-mq: fix hctx/ctx kobject use-after-free"