Merge tag 'rcu-urgent.2022.10.20a' of git://git.kernel.org/pub/scm/linux/kernel/git...

Merge tag 'rcu-urgent.2022.10.20a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull RCU fix from Paul McKenney:
 "Fix a regression caused by commit bf95b2bc3e42 ("rcu: Switch polled
  grace-period APIs to ->gp_seq_polled"), which could incorrectly leave
  interrupts enabled after an early-boot call to synchronize_rcu().

  Such synchronize_rcu() calls must acquire leaf rcu_node locks in order
  to properly interact with polled grace periods, but the code did not
  take into account the possibility of synchronize_rcu() being invoked
  from the portion of the boot sequence during which interrupts are
  disabled.

  This commit therefore switches the lock acquisition and release from
  irq to irqsave/irqrestore"

* tag 'rcu-urgent.2022.10.20a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
  rcu: Keep synchronize_rcu() from enabling irqs in early boot