Pull io_uring fixes from Jens Axboe:
 "Here's a set of fixes that should go into 5.5-rc3 for io_uring.

  This is bigger than I'd like it to be, mainly because we're fixing the
  case where an application reuses sqe data right after issue. This
  really must work, or it's confusing. With 5.5 we're flagging us as
  submit stable for the actual data, this must also be the case for
  SQEs.

  Honestly, I'd really like to add another series on top of this, since
  it cleans it up considerable and prevents any SQE reuse by design. I
  posted that here:

    https://lore.kernel.org/io-uring/20191220174742.7449-1-axboe@kernel.dk/T/#u

  and may still send it your way early next week once it's been looked
  at and had some more soak time (does pass all regression tests). With
  that series, we've unified the prep+issue handling, and only the prep
  phase even has access to the SQE.

  Anyway, outside of that, fixes in here for a few other issues that
  have been hit in testing or production"

* tag 'io_uring-5.5-20191220' of git://git.kernel.dk/linux-block:
  io_uring: io_wq_submit_work() should not touch req->rw
  io_uring: don't wait when under-submitting
  io_uring: warn about unhandled opcode
  io_uring: read opcode and user_data from SQE exactly once
  io_uring: make IORING_OP_TIMEOUT_REMOVE deferrable
  io_uring: make IORING_OP_CANCEL_ASYNC deferrable
  io_uring: make IORING_POLL_ADD and IORING_POLL_REMOVE deferrable
  io_uring: make HARDLINK imply LINK
  io_uring: any deferred command must have stable sqe data
  io_uring: remove 'sqe' parameter to the OP helpers that take it
  io_uring: fix pre-prepped issue with force_nonblock == true
  io-wq: re-add io_wq_current_is_worker()
  io_uring: fix sporadic -EFAULT from IORING_OP_RECVMSG
  io_uring: fix stale comment and a few typos