[ANNOUNCE] 4.1.46-rt52

[Julia Cartwright]

Hello RT Folks!

I'm pleased to announce the 4.1.46-rt52 stable release.

You can get this release via the git tree at:

  git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git

  branch: v4.1-rt
  Head SHA1: 6e737a91c1ce923d4e10db831e14cfef9a2459cc

Or to build 4.1.46-rt52 directly, the following patches should be applied:

  http://www.kernel.org/pub/linux/kernel/v4.x/linux-4.1.tar.xz

  http://www.kernel.org/pub/linux/kernel/v4.x/patch-4.1.46.xz

  http://www.kernel.org/pub/linux/kernel/projects/rt/4.1/patch-4.1.46-rt52.patch.xz


You can also build from 4.1.46-rt51 by applying the incremental patch:

  http://www.kernel.org/pub/linux/kernel/projects/rt/4.1/incr/patch-4.1.46-rt51-rt52.patch.xz

Enjoy!
   Julia

Changes from v4.1.46-rt51:
---
Julia Cartwright (2):
      workqueue: fixup rcu check for RT
      Linux 4.1.46-rt52

Sebastian Andrzej Siewior (2):
      PM / CPU: replace raw_notifier with atomic_notifier (fixup)
      kernel/hrtimer: migrate deferred timer on CPU down

---
 kernel/cpu_pm.c       | 7 +++++++
 kernel/time/hrtimer.c | 5 +++++
 kernel/workqueue.c    | 2 +-
 localversion-rt       | 2 +-
 4 files changed, 14 insertions(+), 2 deletions(-)
---
diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c
index 9da42f83ee03..d1d1c3961553 100644
--- a/kernel/cpu_pm.c
+++ b/kernel/cpu_pm.c
@@ -28,8 +28,15 @@ static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls)
 {
 	int ret;
 
+	/*
+	 * __atomic_notifier_call_chain has a RCU read critical section, which
+	 * could be disfunctional in cpu idle. Copy RCU_NONIDLE code to let
+	 * RCU know this.
+	 */
+	rcu_irq_enter_irqson();
 	ret = __atomic_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL,
 		nr_to_call, nr_calls);
+	rcu_irq_exit_irqson();
 
 	return notifier_to_errno(ret);
 }
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 2c6be169bdc7..75c990b00525 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1951,6 +1951,11 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
 		/* Clear the migration state bit */
 		timer->state &= ~HRTIMER_STATE_MIGRATE;
 	}
+#ifdef CONFIG_PREEMPT_RT_BASE
+	list_splice_tail(&old_base->expired, &new_base->expired);
+	if (!list_empty(&new_base->expired))
+		raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+#endif
 }
 
 static void migrate_hrtimers(int scpu)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 6bdcab98501c..90e261c8811e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -363,7 +363,7 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
 			   "RCU or wq->mutex should be held")
 
 #define assert_rcu_or_wq_mutex_or_pool_mutex(wq)			\
-	rcu_lockdep_assert(rcu_read_lock_sched_held() ||		\
+	rcu_lockdep_assert(rcu_read_lock_held() ||			\
 			   lockdep_is_held(&wq->mutex) ||		\
 			   lockdep_is_held(&wq_pool_mutex),		\
 			   "sched RCU, wq->mutex or wq_pool_mutex should be held")
diff --git a/localversion-rt b/localversion-rt
index 75493460c41f..66a5ed8bf3d7 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt51
+-rt52