Pull RCU updates from Neeraj Upadhyay:

 - Documentation and comment updates

 - RCU torture, locktorture updates that include cleanups; nolibc init
   build support for mips, ppc and rv64; testing of mid stall duration
   scenario and fixing fqs task creation conditions

 - Misc fixes, most notably restricting usage of RCU CPU stall
   notifiers, to confine their usage primarily to debug kernels

 - RCU tasks minor fixes

 - lockdep annotation fix for NMI-safe accesses, callback
   advancing/acceleration cleanup and documentation improvements

* tag 'rcu.release.v6.8' of https://github.com/neeraju/linux:
  rcu: Force quiescent states only for ongoing grace period
  doc: Clarify historical disclaimers in memory-barriers.txt
  doc: Mention address and data dependencies in rcu_dereference.rst
  doc: Clarify RCU Tasks reader/updater checklist
  rculist.h: docs: Fix wrong function summary
  Documentation: RCU: Remove repeated word in comments
  srcu: Use try-lock lockdep annotation for NMI-safe access.
  srcu: Explain why callbacks invocations can't run concurrently
  srcu: No need to advance/accelerate if no callback enqueued
  srcu: Remove superfluous callbacks advancing from srcu_gp_start()
  rcu: Remove unused macros from rcupdate.h
  rcu: Restrict access to RCU CPU stall notifiers
  rcu-tasks: Mark RCU Tasks accesses to current->rcu_tasks_idle_cpu
  rcutorture: Add fqs_holdoff check before fqs_task is created
  rcutorture: Add mid-sized stall to TREE07
  rcutorture: add nolibc init support for mips, ppc and rv64
  locktorture: Increase Hamming distance between call_rcu_chain and rcu_call_chains