Pull workqueue fix from Tejun Heo:
"This is a fix for an old bug in workqueue. Workqueue used a mutex to
arbitrate who gets to be the manager of a pool. When the manager role
gets released, the mutex gets unlocked while holding the pool's
irqsafe spinlock. This can lead to deadlocks as mutex's internal
spinlock isn't irqsafe. This got discovered by recent fixes to mutex
lockdep annotations.
The fix is a bit invasive for rc6 but if anything were wrong with the
fix it would likely have already blown up in -next, and we want the
fix in -stable anyway"
* 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: replace pool->manager_arb mutex with a flag