Commit 07b0137c authored Jan 28, 2018 by Linus Torvalds

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A single fix for a ~10 years old problem which causes high resolution
  timers to stop after a CPU unplug/plug cycle due to a stale flag in
  the per CPU hrtimer base struct.

  Paul McKenney was hunting this for about a year, but the heisenbug
  nature made it resistant against debug attempts for quite some time"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Reset hrtimer cpu base proper on CPU hotplug

parents 62444192 d5421ea4

kernel/time/hrtimer.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -655,7 +655,9 @@ static void hrtimer_reprogram(struct hrtimer *timer,
		static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
		{
		base->expires_next = KTIME_MAX;
		base->hang_detected = 0;
		base->hres_active = 0;
		base->next_timer = NULL;
		}

		/*
		@@ -1589,6 +1591,7 @@ int hrtimers_prepare_cpu(unsigned int cpu)
		timerqueue_init_head(&cpu_base->clock_base[i].active);
		}

		cpu_base->active_bases = 0;
		cpu_base->cpu = cpu;
		hrtimer_init_hres(cpu_base);
		return 0;