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

Pull timer fixes from Ingo Molnar:
 "Fix four timer locking races: two were noticed by Linus while
  reviewing the code while chasing for a corruption bug, and two
  from fixing spurious USB timeouts"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Prevent base clock corruption when forwarding
  timers: Prevent base clock rewind when forwarding clock
  timers: Lock base for same bucket optimization
  timers: Plug locking race vs. timer migration