Merge branch 'for-linus' of git://

Pull one last block fix from Jens Axboe:
 "We've had an issue with scsi-mq where probing takes forever.  This was
  bisected down to the percpu changes for blk_mq_queue_enter(), and the
  fact we now suffer an RCU grace period when killing a queue.  SCSI
  creates and destroys tons of queues, so this let to 10s of seconds of
  stalls at boot for some.

  Tejun has a real fix for this, but it's too involved for 3.17.  So
  this is a temporary workaround to expedite the queue killing until we
  can fold in the real fix for 3.18 when that merge window opens"

* 'for-linus' of git://
  blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe