Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

Pull core kernel fixes from Ingo Molnar:
 "This is a complex task_work series from Oleg that fixes the bug that
  this VFS commit tried to fix:

    d35abdb28824 hold task_lock around checks in keyctl

  but solves the problem without the lockup regression that d35abdb28824
  introduced in v3.6.

  This series came late in v3.6 and I did not feel confident about it so
  late in the cycle.  Might be worth backporting to -stable if it proves
  itself upstream."

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  task_work: Simplify the usage in ptrace_notify() and get_signal_to_deliver()
  task_work: Revert "hold task_lock around checks in keyctl"
  task_work: task_work_add() should not succeed after exit_task_work()
  task_work: Make task_work_add() lockless