Pull RCU fixes from Ingo Molnar: "This fixes sporadic ACPI related hangs in synchronize_rcu() that were caused by the ACPI code mistakenly relying on an aspect of RCU that was neither promised to work nor reliable but which happened to work - until in v4.9 we changed the RCU implementation, which made the hangs more prominent. Since the mis-use of the RCU facility wasn't properly detected and prevented either, these fixes make the RCU side work reliably instead of working around the problem in the ACPI code. Hence the slightly larger diffstat that goes beyond the normal scope of RCU fixes in -rc kernels" * 'rcu-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Narrow early boot window of illegal synchronous grace periods rcu: Remove cond_resched() from Tiny synchronize_sched()